A more refined Event class, with additional tests.

* Add media Python tests

* Add media js test

* Remove try except blocks

* Make Python tests more end-to-end

* Add media Python tests

* Add media js test

* Remove try except blocks

* Make Python tests more end-to-end

* MicroPython explorations.

* Fix websocket tests, so they just skip.

* Fix MicroPython media tests, if no permission is given for a video device.

---------

Co-authored-by: Nicholas H.Tollervey <ntoll@ntoll.org>
Co-authored-by: Andrea Giammarchi <andrea.giammarchi@gmail.com>

.github/ISSUE_TEMPLATE/bug-report.yml

@@ -11,7 +11,9 @@ body:
 
         There will always be more issues than there is time to do them, and so we will need to selectively close issues that don't provide enough information, so we can focus our time on helping people like you who fill out the issue form completely. Thank you for your collaboration!
 
-        There are also already a lot of open issues, so please take 2 minutes and search through existing ones to see if what you are experiencing already exists
+        There are also already a lot of open issues, so please take 2 minutes and search through existing ones to see if what you are experiencing already exists.
+
+        Finally, if you are opening **a bug report related to PyScript.com** please [use this repository instead](https://github.com/anaconda/pyscript-dot-com-issues/issues/new/choose).
 
         Thanks for helping PyScript be amazing. We are nothing without people like you helping build a better community 💐!
   - type: checkboxes

.github/PULL_REQUEST_TEMPLATE.md

@@ -4,12 +4,9 @@
 
 ## Changes
 
-<!-- List the changes done to fix a bug or introduce a new feature.Please note both user-facing changes and changes to internal API's here -->
+<!-- List the technical changes done to fix a bug or introduce a new feature. -->
 
 ## Checklist
 
-<!-- Note: Only user-facing changes require a changelog entry. Internal-only API changes do not require a changelog entry. Changes in documentation do not require a changelog entry. -->
+-   [ ] I have checked `make build` works locally.
-
+-   [ ] I have created / updated documentation for this change (if applicable).
--   [ ] All tests pass locally
--   [ ] I have updated `docs/changelog.md`
--   [ ] I have created documentation for this(if applicable)

.github/dependabot.yml

@@ -0,0 +1,13 @@
+# Keep GitHub Actions up to date with GitHub's Dependabot...
+# https://docs.github.com/en/code-security/dependabot/working-with-dependabot/keeping-your-actions-up-to-date-with-dependabot
+# https://docs.github.com/en/code-security/dependabot/dependabot-version-updates/configuration-options-for-the-dependabot.yml-file#package-ecosystem
+version: 2
+updates:
+    - package-ecosystem: github-actions
+      directory: /
+      groups:
+          github-actions:
+              patterns:
+                  - "*" # Group all Actions updates into a single larger pull request
+      schedule:
+          interval: weekly

.github/workflows/prepare-release.yml

@@ -7,7 +7,7 @@ on:
 
 defaults:
     run:
-        working-directory: ./pyscript.core
+        working-directory: ./core
 
 jobs:
     prepare-release:
@@ -17,12 +17,27 @@ jobs:
               uses: actions/checkout@v4
 
             - name: Install node
-              uses: actions/setup-node@v3
+              uses: actions/setup-node@v4
               with:
-                  node-version: 18.x
+                  node-version: 20.x
+
+            - name: Python venv
+              run: python -m venv env
+
+            - name: Activate Python
+              run: source env/bin/activate
+
+            - name: Update pip
+              run: pip install --upgrade pip
+
+            - name: Install PyMinifier
+              run: pip install --ignore-requires-python python-minifier
+
+            - name: Install Setuptools
+              run: pip install setuptools
 
             - name: Cache node modules
-              uses: actions/cache@v3
+              uses: actions/cache@v4
               env:
                   cache-name: cache-node-modules
               with:
@@ -35,20 +50,20 @@ jobs:
                       ${{ runner.os }}-
 
             - name: NPM Install
-              run: npm install
+              run: npm install && npx playwright install chromium
 
             - name: Build
               run: npm run build
 
             - name: Generate index.html
               working-directory: .
-              run: sed 's#_PATH_#./#' ./public/index.html > ./pyscript.core/dist/index.html
+              run: sed -e 's#_PATH_#./#' -e 's#_DOC_VERSION_#latest#' -e 's#_TAG_VERSION_##' -e 's#_VERSION_#latest#' ./public/index.html > ./core/dist/index.html
 
             - name: Zip dist folder
               run: zip -r -q ./build.zip ./dist
 
             - name: Prepare Release
-              uses: softprops/action-gh-release@v1
+              uses: softprops/action-gh-release@v2
               with:
                   draft: true
                   prerelease: true

.github/workflows/publish-release.yml

@@ -6,7 +6,7 @@ on:
 
 defaults:
     run:
-        working-directory: ./pyscript.core
+        working-directory: ./core
 
 jobs:
     publish-release:
@@ -19,12 +19,27 @@ jobs:
               uses: actions/checkout@v4
 
             - name: Install node
-              uses: actions/setup-node@v3
+              uses: actions/setup-node@v4
               with:
-                  node-version: 18.x
+                  node-version: 20.x
+
+            - name: Python venv
+              run: python -m venv env
+
+            - name: Activate Python
+              run: source env/bin/activate
+
+            - name: Update pip
+              run: pip install --upgrade pip
+
+            - name: Install PyMinifier
+              run: pip install --ignore-requires-python python-minifier
+
+            - name: Install Setuptools
+              run: pip install setuptools
 
             - name: Cache node modules
-              uses: actions/cache@v3
+              uses: actions/cache@v4
               env:
                   cache-name: cache-node-modules
               with:
@@ -37,14 +52,18 @@ jobs:
                       ${{ runner.os }}-
 
             - name: npm install
-              run: npm install
+              run: npm install && npx playwright install chromium
 
             - name: build
               run: npm run build
 
             - name: Generate index.html in snapshot
               working-directory: .
-              run: sed 's#_PATH_#https://pyscript.net/releases/${{ github.ref_name }}/#' ./public/index.html > ./pyscript.core/dist/index.html
+              run: sed -e 's#_PATH_#https://pyscript.net/releases/${{ github.ref_name }}/#' -e 's#_DOC_VERSION_#${{ github.ref_name }}#' -e 's#_TAG_VERSION_#/tag/${{ github.ref_name }}#' -e 's#_VERSION_#${{ github.ref_name }}#' ./public/index.html > ./core/dist/index.html
+
+            - name: Generate release.tar from snapshot and put it in dist/
+              working-directory: .
+              run: tar -cvf ../release.tar * && mv ../release.tar .
 
             - name: Configure AWS credentials
               uses: aws-actions/configure-aws-credentials@v4

.github/workflows/publish-snapshot.yml

@@ -10,7 +10,7 @@ on:
 
 defaults:
     run:
-        working-directory: ./pyscript.core
+        working-directory: ./core
 
 jobs:
     publish-snapshot:
@@ -23,12 +23,27 @@ jobs:
               uses: actions/checkout@v4
 
             - name: Install node
-              uses: actions/setup-node@v3
+              uses: actions/setup-node@v4
               with:
-                  node-version: 18.x
+                  node-version: 20.x
+
+            - name: Python venv
+              run: python -m venv env
+
+            - name: Activate Python
+              run: source env/bin/activate
+
+            - name: Update pip
+              run: pip install --upgrade pip
+
+            - name: Install PyMinifier
+              run: pip install --ignore-requires-python python-minifier
+
+            - name: Install Setuptools
+              run: pip install setuptools
 
             - name: Cache node modules
-              uses: actions/cache@v3
+              uses: actions/cache@v4
               env:
                   cache-name: cache-node-modules
               with:
@@ -41,7 +56,7 @@ jobs:
                       ${{ runner.os }}-
 
             - name: Install Dependencies
-              run: npm install
+              run: npm install && npx playwright install chromium
 
             - name: Build Pyscript.core
               run: npm run build
@@ -54,7 +69,7 @@ jobs:
 
             - name: Generate index.html in snapshot
               working-directory: .
-              run: sed 's#_PATH_#https://pyscript.net/snapshots/${{ inputs.snapshot_version }}/#' ./public/index.html > ./pyscript.core/dist/index.html
+              run: sed -e 's#_PATH_#https://pyscript.net/snapshots/${{ inputs.snapshot_version }}/#' -e 's#_DOC_VERSION_#${{ inputs.snapshot_version }}#' -e 's#_TAG_VERSION_#/tag/${{ inputs.snapshot_version }}#' -e 's#_VERSION_#${{ inputs.snapshot_version }}#' ./public/index.html > ./core/dist/index.html
 
             - name: Copy to Snapshot
               run: >

.github/workflows/publish-unstable.yml

@@ -1,11 +1,11 @@
 name: "Publish Unstable"
 
 on:
-    push: # Only run on merges into main that modify files under pyscript.core/ and examples/
+    push: # Only run on merges into main that modify files under core/ and examples/
         branches:
             - main
         paths:
-            - pyscript.core/**
+            - core/**
             - examples/**
 
     workflow_dispatch:
@@ -18,18 +18,33 @@ jobs:
             contents: read
         defaults:
             run:
-                working-directory: ./pyscript.core
+                working-directory: ./core
         steps:
             - name: Checkout
               uses: actions/checkout@v4
 
             - name: Install node
-              uses: actions/setup-node@v3
+              uses: actions/setup-node@v4
               with:
-                  node-version: 18.x
+                  node-version: 20.x
+
+            - name: Python venv
+              run: python -m venv env
+
+            - name: Activate Python
+              run: source env/bin/activate
+
+            - name: Update pip
+              run: pip install --upgrade pip
+
+            - name: Install PyMinifier
+              run: pip install --ignore-requires-python python-minifier
+
+            - name: Install Setuptools
+              run: pip install setuptools
 
             - name: Cache node modules
-              uses: actions/cache@v3
+              uses: actions/cache@v4
               env:
                   cache-name: cache-node-modules
               with:
@@ -42,14 +57,14 @@ jobs:
                       ${{ runner.os }}-
 
             - name: NPM Install
-              run: npm install
+              run: npm install && npx playwright install chromium
 
             - name: Build
               run: npm run build
 
             - name: Generate index.html in snapshot
               working-directory: .
-              run: sed 's#_PATH_#https://pyscript.net/unstable/#' ./public/index.html > ./pyscript.core/dist/index.html
+              run: sed -e 's#_PATH_#./#' -e 's#_DOC_VERSION_#latest#' -e 's#_TAG_VERSION_##' -e 's#_VERSION_#latest#' ./public/index.html > ./core/dist/index.html
 
             - name: Configure AWS credentials
               uses: aws-actions/configure-aws-credentials@v4

.github/workflows/test.yml

@@ -5,20 +5,20 @@ on:
         branches:
             - main
         paths:
-            - pyscript.core/**
+            - core/**
             - .github/workflows/test.yml
 
     pull_request: # Only run on merges into main that modify certain files
         branches:
             - main
         paths:
-            - pyscript.core/**
+            - core/**
             - .github/workflows/test.yml
     workflow_dispatch:
 
 jobs:
     BuildAndTest:
-        runs-on: ubuntu-latest-8core
+        runs-on: ubuntu-latest
         env:
             MINICONDA_PYTHON_VERSION: py38
             MINICONDA_VERSION: 4.11.0
@@ -37,12 +37,12 @@ jobs:
               run: git log --graph -3
 
             - name: Install node
-              uses: actions/setup-node@v3
+              uses: actions/setup-node@v4
               with:
                   node-version: 20.x
 
             - name: Cache node modules
-              uses: actions/cache@v3
+              uses: actions/cache@v4
               env:
                   cache-name: cache-node-modules
               with:
@@ -55,29 +55,26 @@ jobs:
                       ${{ runner.os }}-
 
             - name: setup Miniconda
-              uses: conda-incubator/setup-miniconda@v2
+              uses: conda-incubator/setup-miniconda@v3
 
-            - name: Setup Environment
+            - name: Create and activate virtual environment
-              run: make setup
+              run: |
+                  python3 -m venv test_venv
+                  source test_venv/bin/activate
+                  echo PATH=$PATH >> $GITHUB_ENV
+                  echo VIRTUAL_ENV=$VIRTUAL_ENV >> $GITHUB_ENV
+
+            - name: Setup dependencies in virtual environment
+              run: |
+                  make setup
 
             - name: Build
-              run: make build
+              run: make build # Integration tests run in the build step.
 
-            - name: Integration Tests
+            - uses: actions/upload-artifact@v4
-              #run: make test-integration-parallel
-              run: make test-integration
-
-            - uses: actions/upload-artifact@v3
               with:
                   name: pyscript
                   path: |
-                      pyscript.core/dist/
+                      core/dist/
                   if-no-files-found: error
                   retention-days: 7
-
-            - uses: actions/upload-artifact@v3
-              if: success() || failure()
-              with:
-                  name: test_results
-                  path: test_results/
-                  if-no-files-found: error

.github/workflows/test_report.yml

@@ -1,16 +0,0 @@
-name: Test Report
-on:
-    workflow_run:
-        workflows: ['\[CI\] Test']
-        types:
-            - completed
-jobs:
-    report:
-        runs-on: ubuntu-latest-8core
-        steps:
-            - uses: dorny/test-reporter@v1.6.0
-              with:
-                  artifact: test_results
-                  name: Test reports
-                  path: "*.xml"
-                  reporter: java-junit

.gitignore

@@ -142,8 +142,11 @@ coverage/
 test_results
 
 # @pyscript/core npm artifacts
-pyscript.core/core.*
+core/test-results/*
-pyscript.core/dist
+core/core.*
-pyscript.core/dist
+core/dist
-pyscript.core/src/plugins.js
+core/dist.zip
-pyscript.core/src/stdlib/pyscript.js
+core/src/plugins.js
+core/src/stdlib/pyscript.js
+core/src/3rd-party/*
+!core/src/3rd-party/READMEmd

.pre-commit-config.yaml

@@ -4,10 +4,10 @@ ci:
     #skip: [eslint]
     autoupdate_schedule: monthly
 
-default_stages: [commit]
+default_stages: [pre-commit]
 repos:
     - repo: https://github.com/pre-commit/pre-commit-hooks
-      rev: v4.4.0
+      rev: v5.0.0
       hooks:
           - id: check-builtin-literals
           - id: check-case-conflict
@@ -21,33 +21,33 @@ repos:
           - id: check-yaml
           - id: detect-private-key
           - id: end-of-file-fixer
-            exclude: pyscript\.core/dist|\.min\.js$
+            exclude: core/dist|\.min\.js$
           - id: trailing-whitespace
 
     - repo: https://github.com/psf/black
-      rev: 23.1.0
+      rev: 25.1.0
       hooks:
           - id: black
-            exclude: pyscript\.core/src/stdlib/pyscript/__init__\.py
+            exclude: core/tests
+            args: ["-l", "88", "--skip-string-normalization"]
 
     - repo: https://github.com/codespell-project/codespell
-      rev: v2.2.4
+      rev: v2.4.1
       hooks:
           - id: codespell # See 'pyproject.toml' for args
-            exclude: \.js\.map$
+            exclude: fs\.py|\.js\.map$
             additional_dependencies:
                 - tomli
 
+    - repo: https://github.com/astral-sh/ruff-pre-commit
+      rev: v0.9.6
+      hooks:
+          - id: ruff
+            exclude: core/tests
+
     - repo: https://github.com/hoodmane/pyscript-prettier-precommit
       rev: "v3.0.0-alpha.6"
       hooks:
           - id: prettier
-            exclude: pyscript\.core/test|pyscript\.core/dist|pyscript\.core/types|pyscript.core/src/stdlib/pyscript.js|pyscript\.sw/
+            exclude: core/tests|core/dist|core/types|core/src/stdlib/pyscript.js|pyscript\.sw/|core/src/3rd-party
             args: [--tab-width, "4"]
-
-    - repo: https://github.com/pycqa/isort
-      rev: 5.12.0
-      hooks:
-          - id: isort
-            name: isort (python)
-            args: [--profile, black]

.prettierignore

@@ -1,5 +1,3 @@
 ISSUE_TEMPLATE
 *.min.*
 package-lock.json
-docs
-examples/panel.html

.readthedocs.yml

@@ -1,28 +0,0 @@
-# .readthedocs.yaml
-# Read the Docs configuration file
-# See https://docs.readthedocs.io/en/stable/config-file/v2.html for details
-
-# Required
-version: 2
-
-# Set the version of Python and other tools you might need
-build:
-    os: ubuntu-20.04
-    tools:
-        python: miniconda3-4.7
-
-# Build documentation in the docs/ directory with Sphinx
-sphinx:
-    configuration: docs/conf.py
-
-conda:
-    environment: docs/environment.yml
-
-# If using Sphinx, optionally build your docs in additional formats such as PDF
-# formats:
-#    - pdf
-
-# Optionally declare the Python requirements required to build your docs
-python:
-    install:
-        - requirements: docs/requirements.txt

CONTRIBUTING.md

@@ -1,81 +1,4 @@
 # Contributing to PyScript
 
-Thank you for wanting to contribute to the PyScript project!
+Please see our guide to contributing to PyScript
-
+[in our documentation](https://docs.pyscript.net/latest/contributing/).
-## Table of contents
-
--   [Contributing to PyScript](#contributing-to-pyscript)
-    -   [Table of contents](#table-of-contents)
--   [Code of Conduct](#code-of-conduct)
--   [Contributing](#contributing)
-    -   [Reporting bugs](#reporting-bugs)
-    -   [Creating useful issues](#creating-useful-issues)
-    -   [Reporting security issues](#reporting-security-issues)
-    -   [Asking questions](#asking-questions)
-    -   [Setting up your local environment and developing](#setting-up-your-local-environment-and-developing)
-    -   [Developing](#developing)
-    -   [Rebasing changes](#rebasing-changes)
-    -   [Building the docs](#building-the-docs)
-    -   [Places to start](#places-to-start)
-    -   [Setting up your local environment and developing](#setting-up-your-local-environment-and-developing)
-    -   [Submitting a change](#submitting-a-change)
--   [License terms for contributions](#license-terms-for-contributions)
--   [Becoming a maintainer](#becoming-a-maintainer)
--   [Trademarks](#trademarks)
-
-# Code of Conduct
-
-The [PyScript Code of Conduct](https://github.com/pyscript/governance/blob/main/CODE-OF-CONDUCT.md) governs the project and everyone participating in it. By participating, you are expected to uphold this code. Please report unacceptable behavior to the maintainers or administrators as described in that document.
-
-# Contributing
-
-## Reporting bugs
-
-Bugs are tracked on the [project issues page](https://github.com/pyscript/pyscript/issues). Please check if your issue has already been filed by someone else by searching the existing issues before filing a new one. Once your issue is filed, it will be triaged by another contributor or maintainer. If there are questions raised about your issue, please respond promptly.
-
-## Creating useful issues
-
--   Use a clear and descriptive title.
--   Describe the specific steps that reproduce the problem with as many details as possible so that someone can verify the issue.
--   Describe the behavior you observed, and the behavior you had expected.
--   Include screenshots if they help make the issue clear.
-
-## Reporting security issues
-
-If you aren't confident that it is appropriate to submit a security issue using the above process, you can e-mail it to security@pyscript.net
-
-## Asking questions
-
-If you have questions about the project, using PyScript, or anything else, please ask in the [PyScript forum](https://community.anaconda.cloud/c/tech-topics/pyscript).
-
-## Places to start
-
-If you would like to contribute to PyScript, but you aren't sure where to begin, here are some suggestions:
-
--   **Read over the existing documentation.** Are there things missing, or could they be clearer? Make some changes/additions to those documents.
--   **Review the open issues.** Are they clear? Can you reproduce them? You can add comments, clarifications, or additions to those issues. If you think you have an idea of how to address the issue, submit a fix!
--   **Look over the open pull requests.** Do you have comments or suggestions for the proposed changes? Add them.
--   **Check out the examples.** Is there a use case that would be good to have sample code for? Create an example for it.
-
-## Setting up your local environment and developing
-
-If you would like to contribute to PyScript, you will need to set up a local development environment. The [following instructions](https://docs.pyscript.net/latest/development/setting-up-environment.html) will help you get started.
-
-You can also read about PyScript's [development process](https://docs.pyscript.net/latest/development/developing.html) to learn how to contribute code to PyScript, how to run tests and what's the PR etiquette of the community!
-
-## License terms for contributions
-
-This Project welcomes contributions, suggestions, and feedback. All contributions, suggestions, and feedback you submitted are accepted under the [Apache 2.0](./LICENSE) license. You represent that if you do not own copyright in the code that you have the authority to submit it under the [Apache 2.0](./LICENSE) license. All feedback, suggestions, or contributions are not confidential.
-
-## Becoming a maintainer
-
-Contributors are invited to be maintainers of the project by demonstrating good decision making in their contributions, a commitment to the goals of the project, and consistent adherence to the [code of conduct](https://github.com/pyscript/governance/blob/main/CODE-OF-CONDUCT.md). New maintainers are invited by a 3/4 vote of the existing maintainers.
-
-## Trademarks
-
-The Project abides by the Organization's [trademark policy](https://github.com/pyscript/governance/blob/main/TRADEMARKS.md).
-
----
-
-Part of MVG-0.1-beta.
-Made with love by GitHub. Licensed under the [CC-BY 4.0 License](https://creativecommons.org/licenses/by-sa/4.0/).

LICENSE

@@ -186,7 +186,11 @@
       same "printed page" as the copyright notice for easier
       identification within third-party archives.
 
-   Copyright [yyyy] [name of copyright owner]
+
+   Copyright (c) 2022-present, PyScript Development Team
+
+   Originated at Anaconda, Inc. in 2022
+
 
    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.

Makefile

@@ -1,122 +1,93 @@
-tag := latest
+MIN_NODE_VER := 20
-git_hash ?= $(shell git log -1 --pretty=format:%h)
+MIN_NPM_VER  := 6
+MIN_PY3_VER  := 8
+NODE_VER     := $(shell node -v | cut -d. -f1 | sed 's/^v\(.*\)/\1/')
+NPM_VER      := $(shell npm -v | cut -d. -f1)
+PY3_VER      := $(shell python3 -c "import sys;t='{v[1]}'.format(v=list(sys.version_info[:2]));print(t)")
+PY_OK        := $(shell python3 -c "print(int($(PY3_VER) >= $(MIN_PY3_VER)))")
 
-base_dir ?= $(shell git rev-parse --show-toplevel)
+all:
-examples ?=  ../$(base_dir)/examples
+	@echo "\nThere is no default Makefile target right now. Try:\n"
-app_dir ?= $(shell git rev-parse --show-prefix)
+	@echo "make setup - check your environment and install the dependencies."
-
+	@echo "make update - update dependencies."
-CONDA_EXE := conda
+	@echo "make clean - clean up auto-generated assets."
-CONDA_ENV ?= $(base_dir)/env
+	@echo "make build - build PyScript."
-env := $(CONDA_ENV)
+	@echo "make precommit-check - run the precommit checks (run eslint)."
-conda_run := $(CONDA_EXE) run -p $(env)
+	@echo "make test - run all automated tests in playwright."
-PYTEST_EXE := $(CONDA_ENV)/bin/pytest
+	@echo "make fmt - format the code."
-
+	@echo "make fmt-check - check the code formatting.\n"
-MIN_NODE_VER := 14
-MIN_NPM_VER := 6
-NODE_VER    := $(shell node -v | cut -d. -f1 | sed 's/^v\(.*\)/\1/')
-NPM_VER     := $(shell npm -v | cut -d. -f1)
-
-ifeq ($(shell uname -s), Darwin)
-    SED_I_ARG := -i ''
-else
-    SED_I_ARG := -i
-endif
 
 .PHONY: check-node
 check-node:
 	@if [ $(NODE_VER) -lt $(MIN_NODE_VER) ]; then \
-		echo "Build requires Node $(MIN_NODE_VER).x or higher: $(NODE_VER) detected"; \
+		echo "\033[0;31mBuild requires Node $(MIN_NODE_VER).x or higher: $(NODE_VER) detected.\033[0m"; \
 		false; \
 	fi
 
 .PHONY: check-npm
 check-npm:
 	@if [ $(NPM_VER) -lt $(MIN_NPM_VER) ]; then \
-		echo "Build requires Node $(MIN_NPM_VER).x or higher: $(NPM_VER) detected"; \
+		echo "\033[0;31mBuild requires Node $(MIN_NPM_VER).x or higher: $(NPM_VER) detected.\033[0m"; \
 		false; \
 	fi
 
-setup: check-node check-npm
+.PHONY: check-python
-	cd pyscript.core && npm install && cd ..
+check-python:
-	$(CONDA_EXE) env $(shell [ -d $(env) ] && echo update || echo create) -p $(env) --file environment.yml
+	@if [ $(PY_OK) -eq 0 ]; then \
-	$(conda_run) playwright install
+		echo "\033[0;31mRequires Python 3.$(MIN_PY3_VER).x or higher: 3.$(PY3_VER) detected.\033[0m"; \
-	$(CONDA_EXE) install -c anaconda pytest -y
+		false; \
+	fi
 
+# Check the environment, install the dependencies.
+setup: check-node check-npm check-python
+	cd core && npm ci && cd ..
+ifeq (,$(VIRTUAL_ENV)$(CONDA_PREFIX))
+	echo "\n\n\033[0;31mCannot install Python dependencies. Your virtualenv or conda env is not activated.\033[0m"
+	false
+else
+	python -m pip install -r requirements.txt
+endif
+
+# Clean up generated assets.
 clean:
 	find . -name \*.py[cod] -delete
+	rm -rf $(env) *.egg-info
 	rm -rf .pytest_cache .coverage coverage.xml
 
-clean-all: clean
+# Build PyScript.
-	rm -rf $(env) *.egg-info
+build: precommit-check
+	cd core && npx playwright install chromium && npm run build
 
-shell:
+# Update the dependencies.
-	@export CONDA_ENV_PROMPT='<{name}>'
+update:
-	@echo 'conda activate $(env)'
+	python -m pip install -r requirements.txt --upgrade
 
-dev:
+# Run the precommit checks (run eslint).
-	cd pyscript.core && npm run dev
-
-build:
-	cd pyscript.core && npm run build
-
-# use the following rule to do all the checks done by precommit: in
-# particular, use this if you want to run eslint.
 precommit-check:
 	pre-commit run --all-files
 
-examples:
+# Run all automated tests in playwright.
-	mkdir -p ./examples
+test:
-	cp -r ../examples/* ./examples
+	cd core && npm run test:integration
-	chmod -R 755 examples
-	find ./examples/toga -type f -name '*.html' -exec sed $(SED_I_ARG) s+https://pyscript.net/latest/+../../build/+g {} \;
-	find ./examples/webgl -type f -name '*.html' -exec sed $(SED_I_ARG) s+https://pyscript.net/latest/+../../../build/+g {} \;
-	find ./examples -type f -name '*.html' -exec sed $(SED_I_ARG) s+https://pyscript.net/latest/+../build/+g {} \;
-	npm run build
-	rm -rf ./examples/build
-	mkdir -p ./examples/build
-	cp -R ./build/* ./examples/build
-	@echo "To serve examples run: $(conda_run) python -m http.server 8080 --directory examples"
 
-# run prerequisites and serve pyscript examples at http://localhost:8000/examples/
+# Serve the repository with the correct headers.
-run-examples: setup build examples
+serve:
-	make examples
+	npx mini-coi .
-	npm install
-	make dev
 
-# run all integration tests *including examples* sequentially
+# Format the code.
-# TODO: (fpliger) The cd pyscript.core before running the tests shouldn't be needed but for
+fmt: fmt-py
-# 		but for some reason it seems to bother pytest tmppaths (or test cache?). Unclear.
-test-integration:
-	mkdir -p test_results
-	$(PYTEST_EXE) -vv $(ARGS) pyscript.core/tests/integration/ --log-cli-level=warning --junitxml=test_results/integration.xml
-
-# run all integration tests *except examples* in parallel (examples use too much memory)
-test-integration-parallel:
-	mkdir -p test_results
-	$(PYTEST_EXE) --numprocesses auto -vv $(ARGS) pyscript.core/tests/integration/ --log-cli-level=warning --junitxml=test_results/integration.xml
-
-# run integration tests on only examples sequentially (to avoid running out of memory)
-test-examples:
-	mkdir -p test_results
-	$(PYTEST_EXE) -vv $(ARGS) pyscript.core/tests/integration/ --log-cli-level=warning --junitxml=test_results/integration.xml -k 'zz_examples'
-
-fmt: fmt-py fmt-ts
 	@echo "Format completed"
 
-fmt-check: fmt-ts-check fmt-py-check
+# Check the code formatting.
+fmt-check: fmt-py-check
 	@echo "Format check completed"
 
-fmt-ts:
+# Format Python code.
-	npm run format
-
-fmt-ts-check:
-	npm run format:check
-
 fmt-py:
-	$(conda_run) black --skip-string-normalization .
+	black -l 88 --skip-string-normalization .
-	$(conda_run) isort --profile black .
 
+# Check the format of Python code.
 fmt-py-check:
-	$(conda_run) black -l 88 --check .
+	black -l 88 --check .
 
 .PHONY: $(MAKECMDGOALS)

README.md

@@ -1,56 +1,94 @@
 # PyScript
 
-## What is PyScript
+## PyScript is an open source platform for Python in the browser.
 
-### Summary
+Using PyScript is as simple as:
-
-PyScript is a framework that allows users to create rich Python applications in the browser using HTML's interface and the power of [Pyodide](https://pyodide.org/en/stable/), [WASM](https://webassembly.org/), and modern web technologies.
-
-To get started see the [getting started tutorial](docs/tutorials/getting-started.md).
-
-For examples see [here](examples).
-
-### Longer Version
-
-PyScript is a meta project that aims to combine multiple open technologies into a framework that allows users to create sophisticated browser applications with Python. It integrates seamlessly with the way the DOM works in the browser and allows users to add Python logic in a way that feels natural both to web and Python developers.
-
-## Try PyScript
-
-To try PyScript, import the appropriate pyscript files into the `<head>` tag of your html page with:
 
 ```html
-<head>
+<!doctype html>
-    <link rel="stylesheet" href="https://pyscript.net/latest/pyscript.css" />
+<html lang="en">
-    <script defer src="https://pyscript.net/latest/pyscript.js"></script>
+    <head>
-</head>
+        <meta charset="utf-8" />
+        <meta name="viewport" content="width=device-width,initial-scale=1" />
+        <title>PyScript!</title>
+        <link
+            rel="stylesheet"
+            href="https://pyscript.net/snapshots/2024.9.2/core.css"
+        />
+        <script
+            type="module"
+            src="https://pyscript.net/snapshots/2024.9.2/core.js"
+        ></script>
+    </head>
+    <body>
+        <!-- Use MicroPython to evaluate some Python -->
+        <script type="mpy" terminal>
+            print("Hello, world!")
+        </script>
+    </body>
+</html>
 ```
 
-You can then use PyScript components in your html page. PyScript currently implements the following elements:
+PyScript enables the creation of rich Python applications in the browser using
+[Pyodide](https://pyodide.org/en/stable/) (a version of
+[CPython](https://python.org/)), [MicroPython](https://micropython.org/),
+[WASM](https://webassembly.org/), and modern web technologies. It means Python
+now runs anywhere a browser runs: desktop, laptop, mobile, tablet, or any other
+browser enabled device.
 
--   `<py-script>`: can be used to define python code that is executable within the web page. The element itself is not rendered to the page and is only used to add logic
+To start building, read the
--   `<py-repl>`: creates a REPL component that is rendered to the page as a code editor and allows users to write executable code
+[Beginning PyScript tutorial](https://docs.pyscript.net/latest/beginning-pyscript/).
 
-Check out the [the examples directory](examples) folder for more examples on how to use it, all you need to do is open them in Chrome.
+For example applications, see [here](https://pyscript.com/@examples).
 
-## How to Contribute
+Other useful resources:
 
-Read the [contributing guide](CONTRIBUTING.md) to learn about our development process, reporting bugs and improvements, creating issues and asking questions.
+-   Our [Home Page](https://pyscript.net/) as an open source project.
+-   The [official technical docs](https://docs.pyscript.net/).
+-   A [YouTube channel](https://www.youtube.com/@PyScriptTV) with helpful videos
+    and community content.
+-   A free-to-use [online IDE](https://pyscript.com/) for trying PyScript.
+-   Our community [Discord Channel](https://discord.gg/BYB2kvyFwm), to keep in
+    touch .
 
-Check out the [developing process](https://docs.pyscript.net/latest/development/developing.html) documentation for more information on how to setup your development environment.
+Every Tuesday at 15:30 UTC there is the _PyScript Community Call_ on zoom,
+where we can talk about PyScript development in the open. Most of the
+maintainers regularly participate in the call, and everybody is welcome to
+join. This meeting is recorded and uploaded to our YouTube channel.
 
-## Resources
+Every other Thursday at 16:00 UTC there is the _PyScript FUN_ call: the focus
+of this call is to share fun projects, goofy hacks or clever uses of PyScript.
+It's a supportive, energetic and entertaining meeting. This meeting is also
+recorded and uploaded to our YouTube channel.
 
--   [Official docs](https://docs.pyscript.net)
+For more details on how to join the calls and up to date schedule, consult the
--   [Discussion board](https://community.anaconda.cloud/c/tech-topics/pyscript)
+official calendar:
--   [Home Page](https://pyscript.net/)
--   [Blog Post](https://engineering.anaconda.com/2022/04/welcome-pyscript.html)
--   [Discord Channel](https://discord.gg/BYB2kvyFwm)
 
-## Notes
+-   [Google calendar](https://calendar.google.com/calendar/u/0/embed?src=d3afdd81f9c132a8c8f3290f5cc5966adebdf61017fca784eef0f6be9fd519e0@group.calendar.google.com&ctz=UTC) in UTC time;
+-   [iCal format](https://calendar.google.com/calendar/ical/d3afdd81f9c132a8c8f3290f5cc5966adebdf61017fca784eef0f6be9fd519e0%40group.calendar.google.com/public/basic.ics).
 
--   This is an extremely experimental project, so expect things to break!
+## Contribute
--   PyScript has been only tested on Chrome at the moment.
+
+For technical details of the code, please see the [README](core/README.md) in
+the `core` directory.
+
+Read the [contributing guide](https://docs.pyscript.net/latest/contributing/)
+to learn about our development process, reporting bugs and improvements,
+creating issues and asking questions.
+
+Check out the [development process](https://docs.pyscript.net/latest/developers/)
+documentation for more information on how to setup your development environment.
 
 ## Governance
 
-The [PyScript organization governance](https://github.com/pyscript/governance) is documented in a separate repository.
+The [PyScript organization governance](https://github.com/pyscript/governance)
+is documented in a separate repository.
+
+## Supporters
+
+PyScript is an independent open source project.
+
+However, PyScript was born at [Anaconda Inc](https://anaconda.com/) and its
+core contributors are currently employed by Anaconda to work on PyScript. We
+would like to acknowledge and celebrate Anaconda's continued support of this
+project. Thank you [Anaconda Inc](https://anaconda.com/)!

TROUBLESHOOTING.md

@@ -1,19 +0,0 @@
-# Troubleshooting
-
-This page is meant for troubleshooting common problems with PyScript.
-
-## Table of contents:
-
--   [Make Setup](#make-setup)
-
-## Make setup
-
-A lot of problems related to `make setup` are related to node and npm being outdated. Once npm and node are updated, `make setup` should work. You can follow the steps on the [npm documentation](https://docs.npmjs.com/try-the-latest-stable-version-of-npm) to update npm (the update command for Linux should work for Mac as well). Once npm has been updated you can continue to the instructions to update node below.
-
-To update Node run the following commands in order (Most likely you'll be prompted for your user password, this is normal):
-
-```
-sudo npm cache clean -f
-sudo npm install -g n
-sudo n stable
-```

core/README.md

@@ -0,0 +1,168 @@
+# @pyscript/core
+
+PyScript brings two Python interpreters to the browser:
+
+-   [MicroPython](https://micropython.org/) - a lean and efficient implementation
+    of the Python 3 programming language that includes a small subset of the
+    Python standard library and is optimised to run on microcontrollers and in
+    constrained environments (like the browser).
+-   [Pyodide](https://pyodide.org)) - a port of all CPython to WebAssembly.
+
+These interpreters are compiled to [WebAssembly](https://webassembly.org/)
+(shortened to WASM). The browser provides a secure WASM computing sandbox. Both
+interpreters are compiled to web assembly with
+[Emscripten](https://emscripten.org/). PyScript core maintainers work closely
+with the core maintainers of both MicroPython and Pyodide (and CPython). We
+work hard to ensure PyScript works efficiently in browsers on all platforms:
+desktop, mobile, or elsewhere.
+
+Our technical documentation for using this project can be
+[found here](https://docs.pyscript.net/).
+
+PyScript sits on two further projects (both written in JavaScript):
+
+1. [polyscript](https://github.com/pyscript/polyscript/#readme) - used to
+   bootstrap WASM compiled interpreters in a browser.
+2. [coincident](https://github.com/WebReflection/coincident) - used to simplify
+   worker based tasks.
+
+PyScript itself is mostly written in JavaScript. The test suite for JavaScript
+is in two parts: automated tests run in [playwright](https://playwright.dev/),
+and manual tests you have to run in a browser and check yourself. PyScript also
+has a plugin system so third parties can extend its capabilities with
+JavaScript. Our built-in core plugins can be found in the `src/plugins`
+directory. We describe how to write third party plugins in our
+[developer documentation](https://docs.pyscript.net/latest/user-guide/plugins/).
+
+We provide a `pyscript` namespace containing Python modules for common browser
+based APIs and features (i.e. you can `import pyscript` in Python code running
+inside PyScript, to access these features). The Python code for the `pyscript`
+namespace is in `src/stdlib/pyscript` with the associated test suite in
+`tests/python`. The tests use the browser friendly
+[uPyTest](https://github.com/ntoll/upytest) test framework for checking Python
+code running _within_ PyScript. All the Python tests are run in each each
+available interpreter in both the main thread and a web worker (i.e. the
+test suite is run four times, accounting for each combination of interpreter
+and main/worker context).
+
+When you create a local build all the automated tests (JavaScript and Python)
+are run.
+
+## Developer Guide
+
+Full instructions for setting up a working development environment, how to
+build PyScript and how to test it can be
+[found in our official docs](https://docs.pyscript.net/latest/developers/).
+
+The short version is:
+
+-   Ensure you have Python, node and npm installed.
+-   Create a Python virtual environment.
+-   In the root of this repository `make setup`.
+-   `make build` to build PyScript.
+-   As dependencies change over time, `make update` to keep in sync.
+
+To start using the locally built version of PyScript, you'll need an HTML
+page something like this (note the relative paths to assets in the `dist`
+directory, in the `<head>` of the document):
+
+```html
+<!doctype html>
+<html lang="en">
+    <head>
+        <meta charset="UTF-8" />
+        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+        <title>Pure Python PyScript tests</title>
+        <link rel="stylesheet" href="../../dist/core.css" />
+        <script type="module" src="../../dist/core.js"></script>
+    </head>
+    <body>
+        <script type="mpy" src="./main.py" config="./conf.toml"></script>
+    </body>
+</html>
+```
+
+Once set up, you should be able to run the most common activities via the
+`make` command:
+
+```
+$ make
+
+There is no default Makefile target right now. Try:
+
+make setup - check your environment and install the dependencies.
+make update - update dependencies.
+make clean - clean up auto-generated assets.
+make build - build PyScript.
+make precommit-check - run the precommit checks (run eslint).
+make test - run all automated tests in playwright.
+make fmt - format the code.
+make fmt-check - check the code formatting.
+```
+
+## Artifacts
+
+There are two main artifacts in this project:
+
+-   **stdlib** and its content: `src/stdlib/pyscript.js` exposes, as a
+    JavaScript object literal, all the _Python_ content within the folder
+    (recursively).
+-   **plugins** and its content: `src/plugins.js` exposes all available
+    _dynamic imports_, and is able to instrument the bundler to create files
+    apart from the `_dist/_` folder, so that by default _core_ remains as small
+    as possible.
+
+Accordingly, whenever a file contains this warning at its first line, **please
+do not change such file directly before submitting a merge request**, as that
+file will be overwritten at the next `npm run build` command, either here or
+in _CI_:
+
+```js
+// ⚠️ This file is an artifact: DO NOT MODIFY
+```
+
+## Plugins
+
+While community or third party plugins don't need to be part of this repository
+and can be added just importing `@pyscript/core` as module, there are a few
+plugins that we would like to make available by default and these are
+considered _core plugins_.
+
+To add a _core plugin_ to this project define the plugin entry-point and name
+in the `src/plugins` folder (see the `error.js` example) and create, if
+necessary, a folder with the same name where extra files or dependencies can be
+added.
+
+The _build_ command will include plugins by name as artifacts so that the
+bundler can create ad-hoc files within the `dist/` folder.
+
+## Python
+
+The `pyscript` package available in _Python_ lives in the folder
+`src/stdlib/pyscript/`.
+
+All _Python_ files will be embedded automatically whenever `npm run build`
+happens and reflected into the `src/stdlib/pyscript.js` file.
+
+Its _core_ responsibility is to ensure those files will be available through
+the filesystem in either the _main_ thread, or any _worker_.
+
+## Release
+
+To cut a new release of PyScript simply
+[add a new release](https://github.com/pyscript/pyscript/releases) while
+remembering to write a comprehensive changelog. A
+[GitHub action](https://github.com/pyscript/pyscript/blob/main/.github/workflows/publish-release.yml)
+will kick in and ensure the release is described and deployed to a URL with the
+pattern: https://pyscript.net/releases/YYYY.M.v/ (year/month/version - as per
+our [CalVer](https://calver.org/) versioning scheme).
+
+Then, the following three separate repositories need updating:
+
+-   [Documentation](https://github.com/pyscript/docs) - Change the `version.json`
+    file in the root of the directory and then `node version-update.js`.
+-   [Homepage](https://github.com/pyscript/pyscript.net) - Ensure the version
+    referenced in `index.html` is the latest version.
+-   [PSDC](https://pyscript.com) - Use discord or Anaconda Slack (if you work at
+    Anaconda) to let the PSDC team know there's a new version, so they can update
+    their project templates.

core/dev.cjs

@@ -0,0 +1,31 @@
+let queue = Promise.resolve();
+
+const { exec } = require("node:child_process");
+
+const build = (fileName) => {
+    if (fileName) console.log(fileName, "changed");
+    else console.log("building without optimizations");
+    queue = queue.then(
+        () =>
+            new Promise((resolve) => {
+                exec(
+                    "npm run build:stdlib && npm run build:plugins && npm run build:core",
+                    { cwd: __dirname, env: { ...process.env, NO_MIN: true } },
+                    (error) => {
+                        if (error) console.error(error);
+                        else console.log(fileName || "", "build completed");
+                        resolve();
+                    },
+                );
+            }),
+    );
+};
+
+const options = {
+    ignored: /\/(?:toml|plugins|pyscript)\.[mc]?js$/,
+    persistent: true,
+};
+
+require("chokidar").watch("./src", options).on("change", build);
+
+build();

core/eslint.config.mjs

@@ -0,0 +1,22 @@
+import globals from "globals";
+import js from "@eslint/js";
+
+export default [
+    js.configs.recommended,
+    {
+        ignores: ["**/3rd-party/"],
+    },
+    {
+        languageOptions: {
+            ecmaVersion: "latest",
+            sourceType: "module",
+            globals: {
+                ...globals.browser,
+                ...globals.es2021,
+            },
+        },
+        rules: {
+            "no-implicit-globals": ["error"],
+        },
+    },
+];

core/package.json

@@ -0,0 +1,111 @@
+{
+    "name": "@pyscript/core",
+    "version": "0.6.39",
+    "type": "module",
+    "description": "PyScript",
+    "module": "./index.js",
+    "unpkg": "./index.js",
+    "jsdelivr": "./jsdelivr.js",
+    "browser": "./index.js",
+    "main": "./index.js",
+    "engines": {
+        "node": ">=20"
+    },
+    "files": [
+        "./dist/",
+        "./src/",
+        "./types/",
+        "./index.js",
+        "./jsdelivr.js",
+        "LICENSE",
+        "README.md"
+    ],
+    "exports": {
+        ".": {
+            "types": "./types/core.d.ts",
+            "import": "./src/core.js"
+        },
+        "./js": {
+            "types": "./types/core.d.ts",
+            "import": "./dist/core.js"
+        },
+        "./css": {
+            "import": "./dist/core.css"
+        },
+        "./storage": {
+            "import": "./dist/storage.js"
+        },
+        "./package.json": "./package.json"
+    },
+    "scripts": {
+        "server": "echo \"➡️  TESTS @ $(tput bold)http://localhost:8080/tests/$(tput sgr0)\"; npx static-handler --coi .",
+        "build": "export ESLINT_USE_FLAT_CONFIG=true;npm run build:3rd-party && npm run build:stdlib && npm run build:plugins && npm run build:core && npm run build:tests-index && if [ -z \"$NO_MIN\" ]; then eslint src/ && npm run ts && npm run test:integration; fi",
+        "build:core": "rm -rf dist && rollup --config rollup/core.config.js && cp src/3rd-party/*.css dist/",
+        "build:flatted": "node rollup/flatted.cjs",
+        "build:plugins": "node rollup/plugins.cjs",
+        "build:stdlib": "node rollup/stdlib.cjs",
+        "build:3rd-party": "node rollup/3rd-party.cjs",
+        "build:tests-index": "node rollup/build_test_index.cjs",
+        "clean:3rd-party": "rm src/3rd-party/*.js && rm src/3rd-party/*.css",
+        "test:integration": "npm run test:ws; static-handler --coi . 2>/dev/null & SH_PID=$!; EXIT_CODE=0; (playwright test tests/js_tests.spec.js && playwright test tests/py_tests.main.spec.js && playwright test tests/py_tests.worker.spec.js) || EXIT_CODE=$?; kill $SH_PID 2>/dev/null; exit $EXIT_CODE",
+        "test:ws": "bun tests/javascript/ws/index.js & playwright test tests/javascript/ws/index.spec.js",
+        "dev": "node dev.cjs",
+        "release": "npm run build && npm run zip",
+        "size": "echo -e \"\\033[1mdist/*.js file size\\033[0m\"; for js in $(ls dist/*.js); do cat $js | brotli > ._; echo -e \"\\033[2m$js:\\033[0m $(du -h --apparent-size ._ | sed -e 's/[[:space:]]*._//')\"; rm ._; done",
+        "ts": "rm -rf types && tsc -p .",
+        "zip": "zip -r dist.zip ./dist"
+    },
+    "keywords": [
+        "pyscript",
+        "core"
+    ],
+    "author": "Anaconda Inc.",
+    "license": "APACHE-2.0",
+    "dependencies": {
+        "@ungap/with-resolvers": "^0.1.0",
+        "@webreflection/idb-map": "^0.3.2",
+        "add-promise-listener": "^0.1.3",
+        "basic-devtools": "^0.1.6",
+        "polyscript": "^0.16.22",
+        "sabayon": "^0.6.6",
+        "sticky-module": "^0.1.1",
+        "to-json-callback": "^0.1.1",
+        "type-checked-collections": "^0.1.7"
+    },
+    "devDependencies": {
+        "@codemirror/commands": "^6.8.0",
+        "@codemirror/lang-python": "^6.1.7",
+        "@codemirror/language": "^6.11.0",
+        "@codemirror/state": "^6.5.2",
+        "@codemirror/view": "^6.36.4",
+        "@playwright/test": "^1.51.1",
+        "@rollup/plugin-commonjs": "^28.0.3",
+        "@rollup/plugin-node-resolve": "^16.0.1",
+        "@rollup/plugin-terser": "^0.4.4",
+        "@webreflection/toml-j0.4": "^1.1.3",
+        "@xterm/addon-fit": "^0.10.0",
+        "@xterm/addon-web-links": "^0.11.0",
+        "@xterm/xterm": "^5.5.0",
+        "bun": "^1.2.5",
+        "chokidar": "^4.0.3",
+        "codedent": "^0.1.2",
+        "codemirror": "^6.0.1",
+        "eslint": "^9.22.0",
+        "flatted": "^3.3.3",
+        "rollup": "^4.36.0",
+        "rollup-plugin-postcss": "^4.0.2",
+        "rollup-plugin-string": "^3.0.0",
+        "static-handler": "^0.5.3",
+        "string-width": "^7.2.0",
+        "typescript": "^5.8.2",
+        "xterm-readline": "^1.1.2"
+    },
+    "repository": {
+        "type": "git",
+        "url": "git+https://github.com/pyscript/pyscript.git"
+    },
+    "bugs": {
+        "url": "https://github.com/pyscript/pyscript/issues"
+    },
+    "homepage": "https://github.com/pyscript/pyscript#readme"
+}

core/rollup/3rd-party.cjs

@@ -0,0 +1,77 @@
+const { copyFileSync, writeFileSync } = require("node:fs");
+const { join } = require("node:path");
+
+const CDN = "https://cdn.jsdelivr.net/npm";
+
+const targets = join(__dirname, "..", "src", "3rd-party");
+const node_modules = join(__dirname, "..", "node_modules");
+
+const { devDependencies } = require(join(__dirname, "..", "package.json"));
+
+const v = (name) => devDependencies[name].replace(/[^\d.]/g, "");
+
+const dropSourceMap = (str) =>
+    str.replace(/^\/.+? sourceMappingURL=\/.+$/m, "");
+
+// Fetch a module via jsdelivr CDN `/+esm` orchestration
+// then sanitize the resulting outcome to avoid importing
+// anything via `/npm/...` through Rollup
+const resolve = (name) => {
+    const cdn = `${CDN}/${name}@${v(name)}/+esm`;
+    console.debug("fetching", cdn);
+    return fetch(cdn)
+        .then((b) => b.text())
+        .then((text) =>
+            text.replace(
+                /("|')\/npm\/(.+)?\+esm\1/g,
+                // normalize `/npm/module@version/+esm` as
+                // just `module` so that rollup can do the rest
+                (_, quote, module) => {
+                    const i = module.lastIndexOf("@");
+                    return `${quote}${module.slice(0, i)}${quote}`;
+                },
+            ),
+        );
+};
+
+// create a file rollup can then process and understand
+const reBundle = (name) => Promise.resolve(`export * from "${name}";\n`);
+
+// key/value pairs as:
+//  "3rd-party/file-name.js"
+//    string as content or
+//    Promise<string> as resolved content
+const modules = {
+    // toml
+    "toml.js": join(node_modules, "@webreflection", "toml-j0.4", "toml.js"),
+
+    // xterm
+    "xterm.js": resolve("@xterm/xterm"),
+    "xterm-readline.js": resolve("xterm-readline"),
+    "xterm_addon-fit.js": fetch(`${CDN}/@xterm/addon-fit/+esm`).then((b) =>
+        b.text(),
+    ),
+    "xterm_addon-web-links.js": fetch(
+        `${CDN}/@xterm/addon-web-links/+esm`,
+    ).then((b) => b.text()),
+    "xterm.css": fetch(
+        `${CDN}/@xterm/xterm@${v("@xterm/xterm")}/css/xterm.min.css`,
+    ).then((b) => b.text()),
+
+    // codemirror
+    "codemirror.js": reBundle("codemirror"),
+    "codemirror_state.js": reBundle("@codemirror/state"),
+    "codemirror_lang-python.js": reBundle("@codemirror/lang-python"),
+    "codemirror_language.js": reBundle("@codemirror/language"),
+    "codemirror_view.js": reBundle("@codemirror/view"),
+    "codemirror_commands.js": reBundle("@codemirror/commands"),
+};
+
+for (const [target, source] of Object.entries(modules)) {
+    if (typeof source === "string") copyFileSync(source, join(targets, target));
+    else {
+        source.then((text) =>
+            writeFileSync(join(targets, target), dropSourceMap(text)),
+        );
+    }
+}

core/rollup/build_test_index.cjs

@@ -0,0 +1,73 @@
+const { join } = require("node:path");
+const { lstatSync, readdirSync, writeFileSync } = require("node:fs");
+
+// folders to not consider while crawling
+const EXCLUDE_DIR = new Set(["ws"]);
+
+const TEST_DIR = join(__dirname, "..", "tests");
+
+const TEST_INDEX = join(TEST_DIR, "index.html");
+
+const crawl = (path, tree = {}) => {
+    for (const file of readdirSync(path)) {
+        const current = join(path, file);
+        if (current === TEST_INDEX) continue;
+        if (lstatSync(current).isDirectory()) {
+            if (EXCLUDE_DIR.has(file)) continue;
+            const sub = {};
+            tree[file] = sub;
+            crawl(current, sub);
+            if (!Reflect.ownKeys(sub).length) {
+                delete tree[file];
+            }
+        } else if (file.endsWith(".html")) {
+            const name = file === "index.html" ? "." : file.slice(0, -5);
+            tree[name] = current.replace(TEST_DIR, "");
+        }
+    }
+    return tree;
+};
+
+const createList = (tree) => {
+    const ul = ["<ul>"];
+    for (const [key, value] of Object.entries(tree)) {
+        ul.push("<li>");
+        if (typeof value === "string") {
+            ul.push(`<a href=".${value}">${key}<small>.html</small></a>`);
+        } else {
+            if ("." in value) {
+                ul.push(`<strong><a href=".${value["."]}">${key}</a></strong>`);
+                delete value["."];
+            } else {
+                ul.push(`<strong><span>${key}</span></strong>`);
+            }
+            if (Reflect.ownKeys(value).length) ul.push(createList(value));
+        }
+        ul.push("</li>");
+    }
+    ul.push("</ul>");
+    return ul.join("");
+};
+
+writeFileSync(
+    TEST_INDEX,
+    `<!doctype html>
+<html lang="en">
+    <head>
+        <meta charset="UTF-8">
+        <meta name="viewport" content="width=device-width, initial-scale=1.0">
+        <title>PyScript tests</title>
+        <style>
+            body { font-family: sans-serif; }
+            a {
+                display: block;
+                transition: opacity .3s;
+            }
+            a, span { opacity: .7; }
+            a:hover { opacity: 1; }
+        </style>
+    </head>
+    <body>${createList(crawl(TEST_DIR))}</body>
+</html>
+`,
+);

core/rollup/core.config.js

@@ -2,6 +2,7 @@
 // the default exported as npm entry.
 
 import { nodeResolve } from "@rollup/plugin-node-resolve";
+import commonjs from "@rollup/plugin-commonjs";
 import terser from "@rollup/plugin-terser";
 import postcss from "rollup-plugin-postcss";
 
@@ -11,7 +12,9 @@ export default [
     {
         input: "./src/core.js",
         plugins: plugins.concat(
-            process.env.NO_MIN ? [nodeResolve()] : [nodeResolve(), terser()],
+            process.env.NO_MIN
+                ? [nodeResolve(), commonjs()]
+                : [nodeResolve(), commonjs(), terser()],
         ),
         output: {
             esModule: true,
@@ -37,4 +40,17 @@ export default [
             warn(warning);
         },
     },
+    {
+        input: "./src/storage.js",
+        plugins: plugins.concat(
+            process.env.NO_MIN
+                ? [nodeResolve(), commonjs()]
+                : [nodeResolve(), commonjs(), terser()],
+        ),
+        output: {
+            esModule: true,
+            dir: "./dist",
+            sourcemap: true,
+        },
+    },
 ];

core/rollup/flatted.cjs

@@ -0,0 +1,17 @@
+const { writeFileSync, readFileSync } = require("node:fs");
+const { join } = require("node:path");
+
+const flatted = "# https://www.npmjs.com/package/flatted\n\n";
+const source = join(
+    __dirname,
+    "..",
+    "node_modules",
+    "flatted",
+    "python",
+    "flatted.py",
+);
+const dest = join(__dirname, "..", "src", "stdlib", "pyscript", "flatted.py");
+
+const clear = (str) => String(str).replace(/^#.*/gm, "").trimStart();
+
+writeFileSync(dest, flatted + clear(readFileSync(source)));

core/rollup/plugins.cjs

@@ -13,7 +13,12 @@ for (const file of readdirSync(join(__dirname, "..", "src", "plugins"))) {
         plugins.push(
             // this comment is needed to avoid bundlers eagerly embedding lazy
             // dependencies, causing all sort of issues once in production
-            `    ${key}: () => import(/* webpackIgnore: true */ ${value}),`,
+            // ⚠️ THIS HAS TO BE LIKE THIS or prettier changes it every single time
+            `    ${key}: () =>
+        import(
+            /* webpackIgnore: true */
+            ${value}
+        ),`,
         );
     }
 }

core/rollup/stdlib.cjs

@@ -0,0 +1,66 @@
+const {
+    readdirSync,
+    readFileSync,
+    statSync,
+    writeFileSync,
+} = require("node:fs");
+
+const { spawnSync } = require("node:child_process");
+
+const { join } = require("node:path");
+
+const dedent = require("codedent");
+
+const crawl = (path, json) => {
+    for (const file of readdirSync(path)) {
+        const full = join(path, file);
+        if (/\.py$/.test(file)) {
+            if (process.env.NO_MIN) json[file] = readFileSync(full).toString();
+            else {
+                try {
+                    const {
+                        output: [error, result],
+                    } = spawnSync("pyminify", [
+                        "--remove-literal-statements",
+                        full,
+                    ]);
+                    if (error) {
+                        console.error(error);
+                        process.exit(1);
+                    }
+                    json[file] = result.toString();
+                } catch (error) {
+                    console.error(error);
+                    console.log(
+                        dedent(`
+                            \x1b[1m⚠️  is your env activated?\x1b[0m
+                            \x1b[2mYou need a Python env to run \x1b[0mpyminify\x1b[2m.\x1b[0m
+                            \x1b[2mTo do so, you can try the following:\x1b[0m
+                            python -m venv env
+                            source env/bin/activate
+                            pip install --upgrade pip
+                            pip install --ignore-requires-python python-minifier
+                            pip install setuptools
+                            \x1b[2mand you can then try \x1b[0mnpm run build\x1b[2m again.\x1b[0m
+                        `),
+                    );
+                    process.exit(1);
+                }
+            }
+        } else if (statSync(full).isDirectory() && !file.endsWith("_"))
+            crawl(full, (json[file] = {}));
+    }
+};
+
+const json = {};
+
+crawl(join(__dirname, "..", "src", "stdlib"), json);
+
+writeFileSync(
+    join(__dirname, "..", "src", "stdlib", "pyscript.js"),
+    `// ⚠️ This file is an artifact: DO NOT MODIFY\nexport default ${JSON.stringify(
+        json,
+        null,
+        "  ",
+    )};\n`,
+);

core/src/3rd-party/README.md

@@ -0,0 +1,7 @@
+# PyScript 3rd Party
+
+This folder contains artifacts created via [3rd-party.cjs](../../rollup/3rd-party.cjs).
+
+As we would like to offer a way to run PyScript offline, and we already offer a `dist` folder with all the necessary scripts, we have created a foreign dependencies resolver that allow to lazy-load CDN dependencies out of the box.
+
+Please **note** these dependencies are **not interpreters**, because interpreters have their own mechanism, folders structure, WASM files, and whatnot, to work locally, but at least XTerm or the TOML parser, among other lazy dependencies, should be available within the dist folder.

core/src/3rd-party/codemirror.js

@@ -0,0 +1 @@
+export * from "codemirror";

core/src/3rd-party/codemirror_commands.js

@@ -0,0 +1 @@
+export * from "@codemirror/commands";

core/src/3rd-party/codemirror_lang-python.js

@@ -0,0 +1 @@
+export * from "@codemirror/lang-python";

core/src/3rd-party/codemirror_language.js

@@ -0,0 +1 @@
+export * from "@codemirror/language";

core/src/3rd-party/codemirror_state.js

@@ -0,0 +1 @@
+export * from "@codemirror/state";

core/src/3rd-party/codemirror_view.js

@@ -0,0 +1 @@
+export * from "@codemirror/view";

core/src/3rd-party/xterm.css

@@ -0,0 +1,7 @@
+/**
+ * Minified by jsDelivr using clean-css v5.3.2.
+ * Original file: /npm/@xterm/xterm@5.5.0/css/xterm.css
+ *
+ * Do NOT use SRI with dynamically generated files! More information: https://www.jsdelivr.com/using-sri-with-dynamic-files
+ */
+.xterm{cursor:text;position:relative;user-select:none;-ms-user-select:none;-webkit-user-select:none}.xterm.focus,.xterm:focus{outline:0}.xterm .xterm-helpers{position:absolute;top:0;z-index:5}.xterm .xterm-helper-textarea{padding:0;border:0;margin:0;position:absolute;opacity:0;left:-9999em;top:0;width:0;height:0;z-index:-5;white-space:nowrap;overflow:hidden;resize:none}.xterm .composition-view{background:#000;color:#fff;display:none;position:absolute;white-space:nowrap;z-index:1}.xterm .composition-view.active{display:block}.xterm .xterm-viewport{background-color:#000;overflow-y:scroll;cursor:default;position:absolute;right:0;left:0;top:0;bottom:0}.xterm .xterm-screen{position:relative}.xterm .xterm-screen canvas{position:absolute;left:0;top:0}.xterm .xterm-scroll-area{visibility:hidden}.xterm-char-measure-element{display:inline-block;visibility:hidden;position:absolute;top:0;left:-9999em;line-height:normal}.xterm.enable-mouse-events{cursor:default}.xterm .xterm-cursor-pointer,.xterm.xterm-cursor-pointer{cursor:pointer}.xterm.column-select.focus{cursor:crosshair}.xterm .xterm-accessibility:not(.debug),.xterm .xterm-message{position:absolute;left:0;top:0;bottom:0;right:0;z-index:10;color:transparent;pointer-events:none}.xterm .xterm-accessibility-tree:not(.debug) ::selection{color:transparent}.xterm .xterm-accessibility-tree{user-select:text;white-space:pre}.xterm .live-region{position:absolute;left:-9999px;width:1px;height:1px;overflow:hidden}.xterm-dim{opacity:1!important}.xterm-underline-1{text-decoration:underline}.xterm-underline-2{text-decoration:double underline}.xterm-underline-3{text-decoration:wavy underline}.xterm-underline-4{text-decoration:dotted underline}.xterm-underline-5{text-decoration:dashed underline}.xterm-overline{text-decoration:overline}.xterm-overline.xterm-underline-1{text-decoration:overline underline}.xterm-overline.xterm-underline-2{text-decoration:overline double underline}.xterm-overline.xterm-underline-3{text-decoration:overline wavy underline}.xterm-overline.xterm-underline-4{text-decoration:overline dotted underline}.xterm-overline.xterm-underline-5{text-decoration:overline dashed underline}.xterm-strikethrough{text-decoration:line-through}.xterm-screen .xterm-decoration-container .xterm-decoration{z-index:6;position:absolute}.xterm-screen .xterm-decoration-container .xterm-decoration.xterm-decoration-top-layer{z-index:7}.xterm-decoration-overview-ruler{z-index:8;position:absolute;top:0;right:0;pointer-events:none}.xterm-decoration-top{z-index:2;position:relative}

core/src/3rd-party/xterm_addon-fit.js

@@ -0,0 +1,7 @@
+/**
+ * Bundled by jsDelivr using Rollup v2.79.2 and Terser v5.37.0.
+ * Original file: /npm/@xterm/addon-fit@0.10.0/lib/addon-fit.js
+ *
+ * Do NOT use SRI with dynamically generated files! More information: https://www.jsdelivr.com/using-sri-with-dynamic-files
+ */
+var e,t,r={exports:{}};self;var s=r.exports=(e=t={},Object.defineProperty(e,"__esModule",{value:!0}),e.FitAddon=void 0,e.FitAddon=class{activate(e){this._terminal=e}dispose(){}fit(){const e=this.proposeDimensions();if(!e||!this._terminal||isNaN(e.cols)||isNaN(e.rows))return;const t=this._terminal._core;this._terminal.rows===e.rows&&this._terminal.cols===e.cols||(t._renderService.clear(),this._terminal.resize(e.cols,e.rows))}proposeDimensions(){if(!this._terminal)return;if(!this._terminal.element||!this._terminal.element.parentElement)return;const e=this._terminal._core,t=e._renderService.dimensions;if(0===t.css.cell.width||0===t.css.cell.height)return;const r=0===this._terminal.options.scrollback?0:e.viewport.scrollBarWidth,s=window.getComputedStyle(this._terminal.element.parentElement),i=parseInt(s.getPropertyValue("height")),o=Math.max(0,parseInt(s.getPropertyValue("width"))),n=window.getComputedStyle(this._terminal.element),l=i-(parseInt(n.getPropertyValue("padding-top"))+parseInt(n.getPropertyValue("padding-bottom"))),a=o-(parseInt(n.getPropertyValue("padding-right"))+parseInt(n.getPropertyValue("padding-left")))-r;return{cols:Math.max(2,Math.floor(a/t.css.cell.width)),rows:Math.max(1,Math.floor(l/t.css.cell.height))}}},t),i=r.exports.FitAddon,o=r.exports.__esModule;export{i as FitAddon,o as __esModule,s as default};

core/src/3rd-party/xterm_addon-web-links.js

@@ -0,0 +1,7 @@
+/**
+ * Bundled by jsDelivr using Rollup v2.79.2 and Terser v5.37.0.
+ * Original file: /npm/@xterm/addon-web-links@0.11.0/lib/addon-web-links.js
+ *
+ * Do NOT use SRI with dynamically generated files! More information: https://www.jsdelivr.com/using-sri-with-dynamic-files
+ */
+var e={exports:{}};self;var t=e.exports=(()=>{var e={6:(e,t)=>{function r(e){try{const t=new URL(e),r=t.password&&t.username?`${t.protocol}//${t.username}:${t.password}@${t.host}`:t.username?`${t.protocol}//${t.username}@${t.host}`:`${t.protocol}//${t.host}`;return e.toLocaleLowerCase().startsWith(r.toLocaleLowerCase())}catch(e){return!1}}Object.defineProperty(t,"__esModule",{value:!0}),t.LinkComputer=t.WebLinkProvider=void 0,t.WebLinkProvider=class{constructor(e,t,r,n={}){this._terminal=e,this._regex=t,this._handler=r,this._options=n}provideLinks(e,t){const r=n.computeLink(e,this._regex,this._terminal,this._handler);t(this._addCallbacks(r))}_addCallbacks(e){return e.map((e=>(e.leave=this._options.leave,e.hover=(t,r)=>{if(this._options.hover){const{range:n}=e;this._options.hover(t,r,n)}},e)))}};class n{static computeLink(e,t,o,s){const i=new RegExp(t.source,(t.flags||"")+"g"),[a,l]=n._getWindowedLineStrings(e-1,o),c=a.join("");let d;const p=[];for(;d=i.exec(c);){const e=d[0];if(!r(e))continue;const[t,i]=n._mapStrIdx(o,l,0,d.index),[a,c]=n._mapStrIdx(o,t,i,e.length);if(-1===t||-1===i||-1===a||-1===c)continue;const h={start:{x:i+1,y:t+1},end:{x:c,y:a+1}};p.push({range:h,text:e,activate:s})}return p}static _getWindowedLineStrings(e,t){let r,n=e,o=e,s=0,i="";const a=[];if(r=t.buffer.active.getLine(e)){const e=r.translateToString(!0);if(r.isWrapped&&" "!==e[0]){for(s=0;(r=t.buffer.active.getLine(--n))&&s<2048&&(i=r.translateToString(!0),s+=i.length,a.push(i),r.isWrapped&&-1===i.indexOf(" ")););a.reverse()}for(a.push(e),s=0;(r=t.buffer.active.getLine(++o))&&r.isWrapped&&s<2048&&(i=r.translateToString(!0),s+=i.length,a.push(i),-1===i.indexOf(" ")););}return[a,n]}static _mapStrIdx(e,t,r,n){const o=e.buffer.active,s=o.getNullCell();let i=r;for(;n;){const e=o.getLine(t);if(!e)return[-1,-1];for(let r=i;r<e.length;++r){e.getCell(r,s);const i=s.getChars();if(s.getWidth()&&(n-=i.length||1,r===e.length-1&&""===i)){const e=o.getLine(t+1);e&&e.isWrapped&&(e.getCell(0,s),2===s.getWidth()&&(n+=1))}if(n<0)return[t,r]}t++,i=0}return[t,i]}}t.LinkComputer=n}},t={};function r(n){var o=t[n];if(void 0!==o)return o.exports;var s=t[n]={exports:{}};return e[n](s,s.exports,r),s.exports}var n={};return(()=>{var e=n;Object.defineProperty(e,"__esModule",{value:!0}),e.WebLinksAddon=void 0;const t=r(6),o=/(https?|HTTPS?):[/]{2}[^\s"'!*(){}|\\\^<>`]*[^\s"':,.!?{}|\\\^~\[\]`()<>]/;function s(e,t){const r=window.open();if(r){try{r.opener=null}catch{}r.location.href=t}else console.warn("Opening link blocked as opener could not be cleared")}e.WebLinksAddon=class{constructor(e=s,t={}){this._handler=e,this._options=t}activate(e){this._terminal=e;const r=this._options,n=r.urlRegex||o;this._linkProvider=this._terminal.registerLinkProvider(new t.WebLinkProvider(this._terminal,n,this._handler,r))}dispose(){this._linkProvider?.dispose()}}})(),n})(),r=e.exports.WebLinksAddon,n=e.exports.__esModule;export{r as WebLinksAddon,n as __esModule,t as default};

core/src/config.js

@@ -0,0 +1,160 @@
+/**
+ * This file parses a generic <py-config> or config attribute
+ * to use as base config for all py-script elements, importing
+ * also a queue of plugins *before* the interpreter (if any) resolves.
+ */
+import { $$ } from "basic-devtools";
+
+import TYPES from "./types.js";
+import allPlugins from "./plugins.js";
+import { robustFetch as fetch, getText } from "./fetch.js";
+import { ErrorCode } from "./exceptions.js";
+
+const { BAD_CONFIG, CONFLICTING_CODE } = ErrorCode;
+
+const badURL = (url, expected = "") => {
+    let message = `(${BAD_CONFIG}): Invalid URL: ${url}`;
+    if (expected) message += `\nexpected ${expected} content`;
+    throw new Error(message);
+};
+
+/**
+ * Given a string, returns its trimmed content as text,
+ * fetching it from a file if the content is a URL.
+ * @param {string} config either JSON, TOML, or a file to fetch
+ * @param {string?} type the optional type to enforce
+ * @returns {{json: boolean, toml: boolean, text: string}}
+ */
+export const configDetails = async (config, type) => {
+    let text = config?.trim();
+    // we only support an object as root config
+    let url = "",
+        toml = false,
+        json = /^{/.test(text) && /}$/.test(text);
+    // handle files by extension (relaxing urls parts after)
+    if (!json && /\.(\w+)(?:\?\S*)?$/.test(text)) {
+        const ext = RegExp.$1;
+        if (ext === "json" && type !== "toml") json = true;
+        else if (ext === "toml" && type !== "json") toml = true;
+        else badURL(text, type);
+        url = text;
+        text = (await fetch(url).then(getText)).trim();
+    }
+    return { json, toml: toml || (!json && !!text), text, url };
+};
+
+const conflictError = (reason) => new Error(`(${CONFLICTING_CODE}): ${reason}`);
+
+const relative_url = (url, base = location.href) => new URL(url, base).href;
+
+const syntaxError = (type, url, { message }) => {
+    let str = `(${BAD_CONFIG}): Invalid ${type}`;
+    if (url) str += ` @ ${url}`;
+    return new SyntaxError(`${str}\n${message}`);
+};
+
+const configs = new Map();
+
+for (const [TYPE] of TYPES) {
+    /** @type {() => Promise<[...any]>} A Promise wrapping any plugins which should be loaded. */
+    let plugins;
+
+    /** @type {any} The PyScript configuration parsed from the JSON or TOML object*. May be any of the return types of JSON.parse() or toml-j0.4's parse() ( {number | string | boolean | null | object | Array} ) */
+    let parsed;
+
+    /** @type {Error | undefined} The error thrown when parsing the PyScript config, if any.*/
+    let error;
+
+    /** @type {string | undefined} The `configURL` field to normalize all config operations as opposite of guessing it once resolved */
+    let configURL;
+
+    let config,
+        type,
+        pyElement,
+        pyConfigs = $$(`${TYPE}-config`),
+        attrConfigs = $$(
+            [
+                `script[type="${TYPE}"][config]:not([worker])`,
+                `${TYPE}-script[config]:not([worker])`,
+            ].join(","),
+        );
+
+    // throw an error if there are multiple <py-config> or <mpy-config>
+    if (pyConfigs.length > 1) {
+        error = conflictError(`Too many ${TYPE}-config`);
+    } else {
+        // throw an error if there are <x-config> and config="x" attributes
+        if (pyConfigs.length && attrConfigs.length) {
+            error = conflictError(
+                `Ambiguous ${TYPE}-config VS config attribute`,
+            );
+        } else if (pyConfigs.length) {
+            [pyElement] = pyConfigs;
+            config = pyElement.getAttribute("src") || pyElement.textContent;
+            type = pyElement.getAttribute("type");
+        } else if (attrConfigs.length) {
+            [pyElement, ...attrConfigs] = attrConfigs;
+            config = pyElement.getAttribute("config");
+            // throw an error if dirrent scripts use different configs
+            if (
+                attrConfigs.some((el) => el.getAttribute("config") !== config)
+            ) {
+                error = conflictError(
+                    "Unable to use different configs on main",
+                );
+            }
+        }
+    }
+
+    // catch possible fetch errors
+    if (!error && config) {
+        try {
+            const { json, toml, text, url } = await configDetails(config, type);
+            if (url) configURL = relative_url(url);
+            config = text;
+            if (json || type === "json") {
+                try {
+                    parsed = JSON.parse(text);
+                } catch (e) {
+                    error = syntaxError("JSON", url, e);
+                }
+            } else if (toml || type === "toml") {
+                try {
+                    const { parse } = await import(
+                        /* webpackIgnore: true */ "./3rd-party/toml.js"
+                    );
+                    parsed = parse(text);
+                } catch (e) {
+                    error = syntaxError("TOML", url, e);
+                }
+            }
+        } catch (e) {
+            error = e;
+        }
+    }
+
+    // parse all plugins and optionally ignore only
+    // those flagged as "undesired" via `!` prefix
+    plugins = async () => {
+        const toBeAwaited = [];
+        for (const [key, value] of Object.entries(allPlugins)) {
+            if (error) {
+                if (key === "error") {
+                    // show on page the config is broken, meaning that
+                    // it was not possible to disable error plugin neither
+                    // as that part wasn't correctly parsed anyway
+                    value().then(({ notify }) => notify(error.message));
+                }
+            } else if (!parsed?.plugins?.includes(`!${key}`)) {
+                toBeAwaited.push(value().then(({ default: p }) => p));
+            } else if (key === "error") {
+                toBeAwaited.push(value().then(({ notOnDOM }) => notOnDOM()));
+            }
+        }
+        return await Promise.all(toBeAwaited);
+    };
+
+    configs.set(TYPE, { config: parsed, configURL, plugins, error });
+}
+
+export { configs, relative_url };

core/src/core.css

@@ -0,0 +1,61 @@
+py-script,
+py-config,
+mpy-script,
+mpy-config {
+    display: none;
+}
+
+/* PyEditor */
+.py-editor-box,
+.mpy-editor-box {
+    padding: 0.5rem;
+}
+.py-editor-input,
+.mpy-editor-input {
+    position: relative;
+}
+.py-editor-box::before,
+.mpy-editor-box::before {
+    content: attr(data-env);
+    display: block;
+    font-size: x-small;
+    text-align: end;
+}
+.py-editor-output,
+.mpy-editor-output {
+    white-space: pre;
+}
+.py-editor-run-button,
+.mpy-editor-run-button {
+    position: absolute;
+    display: flex;
+    right: 0.5rem;
+    bottom: 0.5rem;
+    opacity: 0;
+    transition: opacity 0.25s;
+    z-index: 1;
+    padding: 0;
+}
+.py-editor-box:hover .py-editor-run-button,
+.mpy-editor-box:hover .mpy-editor-run-button,
+.py-editor-run-button:focus,
+.py-editor-run-button.running,
+.mpy-editor-run-button:focus,
+.mpy-editor-run-button.running {
+    opacity: 1;
+}
+
+py-terminal span,
+mpy-terminal span {
+    letter-spacing: 0 !important;
+}
+
+dialog.pyscript-fs {
+    border-radius: 8px;
+    border-width: 1px;
+}
+
+dialog.pyscript-fs > div {
+    display: flex;
+    justify-content: space-between;
+}

core/src/core.js

@@ -0,0 +1,369 @@
+/*! (c) PyScript Development Team */
+
+import stickyModule from "sticky-module";
+import "@ungap/with-resolvers";
+
+import {
+    INVALID_CONTENT,
+    Hook,
+    XWorker,
+    assign,
+    dedent,
+    define,
+    defineProperty,
+    dispatch,
+    isSync,
+    queryTarget,
+    unescape,
+    whenDefined,
+} from "polyscript/exports";
+
+import "./all-done.js";
+import TYPES from "./types.js";
+import { configs, relative_url } from "./config.js";
+import sync from "./sync.js";
+import bootstrapNodeAndPlugins from "./plugins-helper.js";
+import { ErrorCode } from "./exceptions.js";
+import { robustFetch as fetch, getText } from "./fetch.js";
+import {
+    hooks,
+    main,
+    worker,
+    codeFor,
+    createFunction,
+    inputFailure,
+} from "./hooks.js";
+import * as fs from "./fs.js";
+
+import codemirror from "./plugins/codemirror.js";
+export { codemirror };
+
+import { stdlib, optional } from "./stdlib.js";
+export { stdlib, optional, inputFailure };
+
+export const donkey = (options) =>
+    import(/* webpackIgnore: true */ "./plugins/donkey.js").then((module) =>
+        module.default(options),
+    );
+
+// generic helper to disambiguate between custom element and script
+const isScript = ({ tagName }) => tagName === "SCRIPT";
+
+// Used to create either Pyodide or MicroPython workers
+// with the PyScript module available within the code
+const [PyWorker, MPWorker] = [...TYPES.entries()].map(
+    ([TYPE, interpreter]) =>
+        /**
+         * A `Worker` facade able to bootstrap on the worker thread only a PyScript module.
+         * @param {string} file the python file to run ina worker.
+         * @param {{config?: string | object, async?: boolean}} [options] optional configuration for the worker.
+         * @returns {Promise<Worker & {sync: object}>}
+         */
+        async function PyScriptWorker(file, options) {
+            await configs.get(TYPE).plugins;
+            const xworker = XWorker.call(
+                new Hook(null, hooked.get(TYPE)),
+                file,
+                {
+                    ...options,
+                    type: interpreter,
+                },
+            );
+            assign(xworker.sync, sync);
+            return xworker.ready;
+        },
+);
+
+// avoid multiple initialization of the same library
+const [
+    {
+        PyWorker: exportedPyWorker,
+        MPWorker: exportedMPWorker,
+        hooks: exportedHooks,
+        config: exportedConfig,
+        whenDefined: exportedWhenDefined,
+    },
+    alreadyLive,
+] = stickyModule("@pyscript/core", {
+    PyWorker,
+    MPWorker,
+    hooks,
+    config: {},
+    whenDefined,
+});
+
+export {
+    TYPES,
+    relative_url,
+    exportedPyWorker as PyWorker,
+    exportedMPWorker as MPWorker,
+    exportedHooks as hooks,
+    exportedConfig as config,
+    exportedWhenDefined as whenDefined,
+};
+
+export const offline_interpreter = (config) =>
+    config?.interpreter && relative_url(config.interpreter);
+
+const hooked = new Map();
+
+for (const [TYPE, interpreter] of TYPES) {
+    // avoid any dance if the module already landed
+    if (alreadyLive) break;
+
+    const dispatchDone = (element, isAsync, result) => {
+        if (isAsync) result.then(() => dispatch(element, TYPE, "done"));
+        else dispatch(element, TYPE, "done");
+    };
+
+    const { config, configURL, plugins, error } = configs.get(TYPE);
+
+    // create a unique identifier when/if needed
+    let id = 0;
+    const getID = (prefix = TYPE) => `${prefix}-${id++}`;
+
+    /**
+     * Given a generic DOM Element, tries to fetch the 'src' attribute, if present.
+     * It either throws an error if the 'src' can't be fetched or it returns a fallback
+     * content as source.
+     */
+    const fetchSource = async (tag, io, asText) => {
+        if (tag.hasAttribute("src")) {
+            try {
+                return await fetch(tag.getAttribute("src")).then(getText);
+            } catch (error) {
+                io.stderr(error);
+            }
+        }
+
+        if (asText) return dedent(tag.textContent);
+
+        const code = dedent(unescape(tag.innerHTML));
+        console.warn(
+            `Deprecated: use <script type="${TYPE}"> for an always safe content parsing:\n`,
+            code,
+        );
+        return code;
+    };
+
+    // register once any interpreter
+    let alreadyRegistered = false;
+
+    // allows lazy element features on code evaluation
+    let currentElement;
+
+    const registerModule = ({ XWorker, interpreter, io }) => {
+        // avoid multiple registration of the same interpreter
+        if (alreadyRegistered) return;
+        alreadyRegistered = true;
+
+        // automatically use the pyscript stderr (when/if defined)
+        // this defaults to console.error
+        function PyWorker(...args) {
+            const worker = XWorker(...args);
+            worker.onerror = ({ error }) => io.stderr(error);
+            return worker;
+        }
+
+        // enrich the Python env with some JS utility for main
+        interpreter.registerJsModule("_pyscript", {
+            PyWorker,
+            fs,
+            interpreter,
+            js_import: (...urls) => Promise.all(urls.map((url) => import(url))),
+            get target() {
+                return isScript(currentElement)
+                    ? currentElement.target.id
+                    : currentElement.id;
+            },
+        });
+    };
+
+    // define the module as both `<script type="py">` and `<py-script>`
+    // but only if the config didn't throw an error
+    if (!error) {
+        // ensure plugins are bootstrapped already before custom type definition
+        // NOTE: we cannot top-level await in here as plugins import other utilities
+        //       from core.js itself so that custom definition should not be blocking.
+        plugins().then(() => {
+            // possible early errors sent by polyscript
+            const errors = new Map();
+
+            // specific main and worker hooks
+            const hooks = {
+                main: {
+                    ...codeFor(main, TYPE),
+                    async onReady(wrap, element) {
+                        registerModule(wrap);
+
+                        // allows plugins to do whatever they want with the element
+                        // before regular stuff happens in here
+                        for (const callback of main("onReady"))
+                            await callback(wrap, element);
+
+                        // now that all possible plugins are configured,
+                        // bail out if polyscript encountered an error
+                        if (errors.has(element)) {
+                            let { message } = errors.get(element);
+                            errors.delete(element);
+                            const clone = message === INVALID_CONTENT;
+                            message = `(${ErrorCode.CONFLICTING_CODE}) ${message} for `;
+                            message += element.cloneNode(clone).outerHTML;
+                            wrap.io.stderr(message);
+                            return;
+                        }
+
+                        if (isScript(element)) {
+                            const isAsync = !isSync(element);
+                            const target = element.getAttribute("target");
+                            const show = target
+                                ? queryTarget(element, target)
+                                : document.createElement("script-py");
+
+                            if (!target) {
+                                const { head, body } = document;
+                                if (head.contains(element)) body.append(show);
+                                else element.after(show);
+                            }
+                            if (!show.id) show.id = getID();
+
+                            // allows the code to retrieve the target element via
+                            // document.currentScript.target if needed
+                            defineProperty(element, "target", { value: show });
+
+                            // notify before the code runs
+                            dispatch(element, TYPE, "ready");
+                            dispatchDone(
+                                element,
+                                isAsync,
+                                wrap[`run${isAsync ? "Async" : ""}`](
+                                    await fetchSource(element, wrap.io, true),
+                                ),
+                            );
+                        } else {
+                            // resolve PyScriptElement to allow connectedCallback
+                            element._wrap.resolve(wrap);
+                        }
+                        console.debug("[pyscript/main] PyScript Ready");
+                    },
+                    onWorker(_, xworker) {
+                        assign(xworker.sync, sync);
+                        for (const callback of main("onWorker"))
+                            callback(_, xworker);
+                    },
+                    onBeforeRun(wrap, element) {
+                        currentElement = element;
+                        bootstrapNodeAndPlugins(
+                            main,
+                            wrap,
+                            element,
+                            "onBeforeRun",
+                        );
+                    },
+                    onBeforeRunAsync(wrap, element) {
+                        currentElement = element;
+                        return bootstrapNodeAndPlugins(
+                            main,
+                            wrap,
+                            element,
+                            "onBeforeRunAsync",
+                        );
+                    },
+                    onAfterRun(wrap, element) {
+                        bootstrapNodeAndPlugins(
+                            main,
+                            wrap,
+                            element,
+                            "onAfterRun",
+                        );
+                    },
+                    onAfterRunAsync(wrap, element) {
+                        return bootstrapNodeAndPlugins(
+                            main,
+                            wrap,
+                            element,
+                            "onAfterRunAsync",
+                        );
+                    },
+                },
+                worker: {
+                    ...codeFor(worker, TYPE),
+                    // these are lazy getters that returns a composition
+                    // of the current hooks or undefined, if no hook is present
+                    get onReady() {
+                        return createFunction(this, "onReady", true);
+                    },
+                    get onBeforeRun() {
+                        return createFunction(this, "onBeforeRun", false);
+                    },
+                    get onBeforeRunAsync() {
+                        return createFunction(this, "onBeforeRunAsync", true);
+                    },
+                    get onAfterRun() {
+                        return createFunction(this, "onAfterRun", false);
+                    },
+                    get onAfterRunAsync() {
+                        return createFunction(this, "onAfterRunAsync", true);
+                    },
+                },
+            };
+
+            hooked.set(TYPE, hooks);
+
+            define(TYPE, {
+                config,
+                configURL,
+                interpreter,
+                hooks,
+                env: `${TYPE}-script`,
+                version: offline_interpreter(config),
+                onerror(error, element) {
+                    errors.set(element, error);
+                },
+            });
+
+            customElements.define(
+                `${TYPE}-script`,
+                class extends HTMLElement {
+                    constructor() {
+                        assign(super(), {
+                            _wrap: Promise.withResolvers(),
+                            srcCode: "",
+                            executed: false,
+                        });
+                    }
+                    get id() {
+                        return super.id || (super.id = getID());
+                    }
+                    set id(value) {
+                        super.id = value;
+                    }
+                    async connectedCallback() {
+                        if (!this.executed) {
+                            this.executed = true;
+                            const isAsync = !isSync(this);
+                            const { io, run, runAsync } = await this._wrap
+                                .promise;
+                            this.srcCode = await fetchSource(
+                                this,
+                                io,
+                                !this.childElementCount,
+                            );
+                            this.replaceChildren();
+                            this.style.display = "block";
+                            dispatch(this, TYPE, "ready");
+                            dispatchDone(
+                                this,
+                                isAsync,
+                                (isAsync ? runAsync : run)(this.srcCode),
+                            );
+                        }
+                    }
+                },
+            );
+        });
+    }
+
+    // export the used config without allowing leaks through it
+    exportedConfig[TYPE] = structuredClone(config);
+}

core/src/exceptions.js

@@ -1,9 +1,11 @@
+import { assign } from "polyscript/exports";
+
 const CLOSEBUTTON =
     "<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='currentColor' width='12px'><path d='M.293.293a1 1 0 011.414 0L8 6.586 14.293.293a1 1 0 111.414 1.414L9.414 8l6.293 6.293a1 1 0 01-1.414 1.414L8 9.414l-6.293 6.293a1 1 0 01-1.414-1.414L6.586 8 .293 1.707a1 1 0 010-1.414z'/></svg>";
 
 /**
  * These error codes are used to identify the type of error that occurred.
- * @see https://docs.pyscript.net/latest/reference/exceptions.html?highlight=errors
+ * @see https://pyscript.github.io/docs/latest/reference/exceptions.html?highlight=errors
  */
 export const ErrorCode = {
     GENERIC: "PY0000", // Use this only for development then change to a more specific error code
@@ -87,13 +89,13 @@ export function _createAlertBanner(
     }
 
     const content = messageType === "html" ? "innerHTML" : "textContent";
-    const banner = Object.assign(document.createElement("div"), {
+    const banner = assign(document.createElement("div"), {
         className: `alert-banner py-${level}`,
         [content]: message,
     });
 
     if (level === "warning") {
-        const closeButton = Object.assign(document.createElement("button"), {
+        const closeButton = assign(document.createElement("button"), {
             id: "alert-close-button",
             innerHTML: CLOSEBUTTON,
         });

core/src/fetch.js

@@ -1,7 +1,10 @@
 import { FetchError, ErrorCode } from "./exceptions.js";
-import { getText } from "../node_modules/polyscript/esm/fetch-utils.js";
 
-export { getText };
+/**
+ * @param {Response} response
+ * @returns
+ */
+export const getText = (response) => response.text();
 
 /**
  * This is a fetch wrapper that handles any non 200 responses and throws a

core/src/fs.js

@@ -0,0 +1,81 @@
+import IDBMap from "@webreflection/idb-map";
+import { assign } from "polyscript/exports";
+import { $$ } from "basic-devtools";
+
+const stop = (event) => {
+    event.preventDefault();
+    event.stopImmediatePropagation();
+};
+
+// ⚠️ these two constants MUST be passed as `fs`
+//     within the worker onBeforeRunAsync hook!
+export const NAMESPACE = "@pyscript.fs";
+export const ERROR = "storage permissions not granted";
+
+export const idb = new IDBMap(NAMESPACE);
+
+/**
+ * Ask a user action via dialog and returns the directory handler once granted.
+ * @param {{id?:string, mode?:"read"|"readwrite", hint?:"desktop"|"documents"|"downloads"|"music"|"pictures"|"videos"}} options
+ * @returns {Promise<FileSystemDirectoryHandle>}
+ */
+export const getFileSystemDirectoryHandle = async (options) => {
+    if (!("showDirectoryPicker" in globalThis)) {
+        return Promise.reject(
+            new Error("showDirectoryPicker is not supported"),
+        );
+    }
+
+    const { promise, resolve, reject } = Promise.withResolvers();
+
+    const how = { id: "pyscript", mode: "readwrite", ...options };
+    if (options.hint) how.startIn = options.hint;
+
+    const transient = async () => {
+        try {
+            /* eslint-disable */
+            const handler = await showDirectoryPicker(how);
+            /* eslint-enable */
+            if ((await handler.requestPermission(how)) === "granted") {
+                resolve(handler);
+                return true;
+            }
+        } catch ({ message }) {
+            console.warn(message);
+        }
+        return false;
+    };
+
+    // in case the user decided to attach the event itself
+    // as opposite of relying our dialog walkthrough
+    if (navigator.userActivation?.isActive) {
+        if (!(await transient())) reject(new Error(ERROR));
+    } else {
+        const dialog = assign(document.createElement("dialog"), {
+            className: "pyscript-fs",
+            innerHTML: [
+                "<strong>ℹ️ Persistent FileSystem</strong><hr>",
+                "<p><small>PyScript would like to access a local folder.</small></p>",
+                "<div><button title='ok'>✅ Authorize</button>",
+                "<button title='cancel'>❌</button></div>",
+            ].join(""),
+        });
+
+        const [ok, cancel] = $$("button", dialog);
+
+        ok.addEventListener("click", async (event) => {
+            stop(event);
+            if (await transient()) dialog.close();
+        });
+
+        cancel.addEventListener("click", async (event) => {
+            stop(event);
+            reject(new Error(ERROR));
+            dialog.close();
+        });
+
+        document.body.appendChild(dialog).showModal();
+    }
+
+    return promise;
+};

core/src/hooks.js

@@ -0,0 +1,117 @@
+import { typedSet } from "type-checked-collections";
+import { dedent } from "polyscript/exports";
+import toJSONCallback from "to-json-callback";
+
+import { stdlib, optional } from "./stdlib.js";
+
+export const main = (name) => hooks.main[name];
+export const worker = (name) => hooks.worker[name];
+
+const code = (hooks, branch, key, lib) => {
+    hooks[key] = () => {
+        const arr = lib ? [lib] : [];
+        arr.push(...branch(key));
+        return arr.map(dedent).join("\n");
+    };
+};
+
+export const codeFor = (branch, type) => {
+    const pylib = type === "mpy" ? stdlib.replace(optional, "") : stdlib;
+    const hooks = {};
+    code(hooks, branch, `codeBeforeRun`, pylib);
+    code(hooks, branch, `codeBeforeRunAsync`, pylib);
+    code(hooks, branch, `codeAfterRun`);
+    code(hooks, branch, `codeAfterRunAsync`);
+    return hooks;
+};
+
+export const createFunction = (self, name) => {
+    const cbs = [...worker(name)];
+    if (cbs.length) {
+        const cb = toJSONCallback(
+            self[`_${name}`] ||
+                (name.endsWith("Async")
+                    ? async (wrap, xworker, ...cbs) => {
+                          for (const cb of cbs) await cb(wrap, xworker);
+                      }
+                    : (wrap, xworker, ...cbs) => {
+                          for (const cb of cbs) cb(wrap, xworker);
+                      }),
+        );
+        const a = cbs.map(toJSONCallback).join(", ");
+        return Function(`return(w,x)=>(${cb})(w,x,...[${a}])`)();
+    }
+};
+
+const SetFunction = typedSet({ typeof: "function" });
+const SetString = typedSet({ typeof: "string" });
+
+export const inputFailure = `
+    import builtins
+    def input(prompt=""):
+        raise Exception("\\n           ".join([
+            "input() doesn't work when PyScript runs in the main thread.",
+            "Consider using the worker attribute: https://pyscript.github.io/docs/2023.11.2/user-guide/workers/"
+        ]))
+
+    builtins.input = input
+    del builtins
+    del input
+`;
+
+export const hooks = {
+    main: {
+        /** @type {Set<function>} */
+        onWorker: new SetFunction(),
+        /** @type {Set<function>} */
+        onReady: new SetFunction(),
+        /** @type {Set<function>} */
+        onBeforeRun: new SetFunction(),
+        /** @type {Set<function>} */
+        onBeforeRunAsync: new SetFunction(),
+        /** @type {Set<function>} */
+        onAfterRun: new SetFunction(),
+        /** @type {Set<function>} */
+        onAfterRunAsync: new SetFunction(),
+        /** @type {Set<string>} */
+        codeBeforeRun: new SetString([inputFailure]),
+        /** @type {Set<string>} */
+        codeBeforeRunAsync: new SetString(),
+        /** @type {Set<string>} */
+        codeAfterRun: new SetString(),
+        /** @type {Set<string>} */
+        codeAfterRunAsync: new SetString(),
+    },
+    worker: {
+        /** @type {Set<function>} */
+        onReady: new SetFunction(),
+        /** @type {Set<function>} */
+        onBeforeRun: new SetFunction(),
+        /** @type {Set<function>} */
+        onBeforeRunAsync: new SetFunction([
+            ({ interpreter }) => {
+                interpreter.registerJsModule("_pyscript", {
+                    // cannot be imported from fs.js
+                    // because this code is stringified
+                    fs: {
+                        ERROR: "storage permissions not granted",
+                        NAMESPACE: "@pyscript.fs",
+                    },
+                    interpreter,
+                });
+            },
+        ]),
+        /** @type {Set<function>} */
+        onAfterRun: new SetFunction(),
+        /** @type {Set<function>} */
+        onAfterRunAsync: new SetFunction(),
+        /** @type {Set<string>} */
+        codeBeforeRun: new SetString(),
+        /** @type {Set<string>} */
+        codeBeforeRunAsync: new SetString(),
+        /** @type {Set<string>} */
+        codeAfterRun: new SetString(),
+        /** @type {Set<string>} */
+        codeAfterRunAsync: new SetString(),
+    },
+};

core/src/plugins-helper.js

@@ -0,0 +1,26 @@
+import { defineProperty } from "polyscript/exports";
+
+// helper for all script[type="py"] out there
+const before = (script) => {
+    defineProperty(document, "currentScript", {
+        configurable: true,
+        get: () => script,
+    });
+};
+
+const after = () => {
+    delete document.currentScript;
+};
+
+// common life-cycle handlers for any node
+export default async (main, wrap, element, hook) => {
+    const isAsync = hook.endsWith("Async");
+    const isBefore = hook.startsWith("onBefore");
+    // make it possible to reach the current target node via Python
+    // or clean up for other scripts executing around this one
+    (isBefore ? before : after)(element);
+    for (const fn of main(hook)) {
+        if (isAsync) await fn(wrap, element);
+        else fn(wrap, element);
+    }
+};

core/src/plugins.js

@@ -0,0 +1,38 @@
+// ⚠️ This file is an artifact: DO NOT MODIFY
+export default {
+    codemirror: () =>
+        import(
+            /* webpackIgnore: true */
+            "./plugins/codemirror.js"
+        ),
+    ["deprecations-manager"]: () =>
+        import(
+            /* webpackIgnore: true */
+            "./plugins/deprecations-manager.js"
+        ),
+    donkey: () =>
+        import(
+            /* webpackIgnore: true */
+            "./plugins/donkey.js"
+        ),
+    error: () =>
+        import(
+            /* webpackIgnore: true */
+            "./plugins/error.js"
+        ),
+    ["py-editor"]: () =>
+        import(
+            /* webpackIgnore: true */
+            "./plugins/py-editor.js"
+        ),
+    ["py-game"]: () =>
+        import(
+            /* webpackIgnore: true */
+            "./plugins/py-game.js"
+        ),
+    ["py-terminal"]: () =>
+        import(
+            /* webpackIgnore: true */
+            "./plugins/py-terminal.js"
+        ),
+};

core/src/plugins/codemirror.js

@@ -0,0 +1,31 @@
+// lazy loaded on-demand codemirror related files
+export default {
+    get core() {
+        return import(/* webpackIgnore: true */ "../3rd-party/codemirror.js");
+    },
+    get state() {
+        return import(
+            /* webpackIgnore: true */ "../3rd-party/codemirror_state.js"
+        );
+    },
+    get python() {
+        return import(
+            /* webpackIgnore: true */ "../3rd-party/codemirror_lang-python.js"
+        );
+    },
+    get language() {
+        return import(
+            /* webpackIgnore: true */ "../3rd-party/codemirror_language.js"
+        );
+    },
+    get view() {
+        return import(
+            /* webpackIgnore: true */ "../3rd-party/codemirror_view.js"
+        );
+    },
+    get commands() {
+        return import(
+            /* webpackIgnore: true */ "../3rd-party/codemirror_commands.js"
+        );
+    },
+};

core/src/plugins/deprecations-manager.js

@@ -0,0 +1,27 @@
+// PyScript Derepcations Plugin
+import { notify } from "./error.js";
+import { hooks } from "../core.js";
+
+// react lazily on PyScript bootstrap
+hooks.main.onReady.add(checkDeprecations);
+hooks.main.onWorker.add(checkDeprecations);
+
+/**
+ * Check that there are no scripts loading from pyscript.net/latest
+ */
+function checkDeprecations() {
+    const scripts = document.querySelectorAll("script");
+    for (const script of scripts) checkLoadingScriptsFromLatest(script.src);
+}
+
+/**
+ * Check if src being loaded from pyscript.net/latest and display a notification if true
+ * * @param {string} src
+ */
+function checkLoadingScriptsFromLatest(src) {
+    if (/\/pyscript\.net\/latest/.test(src)) {
+        notify(
+            "Loading scripts from latest is deprecated and will be removed soon. Please use a specific version instead.",
+        );
+    }
+}

core/src/plugins/donkey.js

@@ -0,0 +1,121 @@
+import addPromiseListener from "add-promise-listener";
+import { assign, dedent } from "polyscript/exports";
+
+const { stringify } = JSON;
+
+const invoke = (name, args) => `${name}(code, ${args.join(", ")})`;
+
+const donkey = ({
+    type = "py",
+    persistent,
+    terminal,
+    config,
+    serviceWorker,
+}) => {
+    const globals = terminal ? '{"__terminal__":__terminal__}' : "{}";
+    const args = persistent ? ["globals()", "__locals__"] : [globals, "{}"];
+
+    const src = URL.createObjectURL(
+        new Blob([
+            [
+                // this array is to better minify this code once in production
+                "from pyscript import sync, config",
+                '__message__ = lambda e,v: f"\x1b[31m\x1b[1m{e.__name__}\x1b[0m: {v}"',
+                "__locals__ = {}",
+                'if config["type"] == "py":',
+                "	import sys",
+                "	def __error__(_):",
+                "		info = sys.exc_info()",
+                "		return __message__(info[0], info[1])",
+                "else:",
+                "	__error__ = lambda e: __message__(e.__class__, e.value)",
+                "def execute(code):",
+                `	try: return ${invoke("exec", args)};`,
+                "	except Exception as e: print(__error__(e));",
+                "def evaluate(code):",
+                `	try: return ${invoke("eval", args)};`,
+                "	except Exception as e: print(__error__(e));",
+                "sync.execute = execute",
+                "sync.evaluate = evaluate",
+            ].join("\n"),
+        ]),
+    );
+
+    // create the script that exposes the code to execute or evaluate
+    const script = assign(document.createElement("script"), { type, src });
+    script.toggleAttribute("worker", true);
+    script.toggleAttribute("terminal", true);
+    if (terminal) script.setAttribute("target", terminal);
+    if (config) {
+        script.setAttribute(
+            "config",
+            typeof config === "string" ? config : stringify(config),
+        );
+    }
+    if (serviceWorker) script.setAttribute("service-worker", serviceWorker);
+
+    return addPromiseListener(
+        document.body.appendChild(script),
+        `${type}:done`,
+        { stopPropagation: true },
+    ).then(() => {
+        URL.revokeObjectURL(src);
+        return script;
+    });
+};
+
+const utils = async (options) => {
+    const script = await donkey(options);
+    const { xworker, process, terminal } = script;
+    const { execute, evaluate } = xworker.sync;
+    script.remove();
+    return {
+        xworker,
+        process,
+        terminal,
+        execute,
+        evaluate,
+    };
+};
+
+export default async (options = {}) => {
+    let farmer = await utils(options);
+    let working = false;
+    const kill = () => {
+        if (farmer) {
+            farmer.xworker.terminate();
+            farmer.terminal.dispose();
+            farmer = null;
+        }
+        working = false;
+    };
+    const reload = async () => {
+        kill();
+        farmer = await utils(options);
+    };
+    const asyncTask = (method) => async (code) => {
+        // race condition ... a new task has been
+        // assigned while the previous one didn't finish
+        if (working) await reload();
+        working = true;
+        try {
+            return await farmer[method](dedent(code));
+        } catch (e) {
+            console.error(e);
+        } finally {
+            working = false;
+        }
+    };
+    const asyncMethod = (method) => async () => {
+        if (working) await reload();
+        else farmer?.terminal[method]();
+    };
+    return {
+        process: asyncTask("process"),
+        execute: asyncTask("execute"),
+        evaluate: asyncTask("evaluate"),
+        clear: asyncMethod("clear"),
+        reset: asyncMethod("reset"),
+        kill,
+    };
+};

core/src/plugins/error.js

@@ -1,20 +1,28 @@
 // PyScript Error Plugin
+import { buffered } from "polyscript/exports";
 import { hooks } from "../core.js";
 
-hooks.onInterpreterReady.add(function override(pyScript) {
+let dontBotherDOM = false;
+export function notOnDOM() {
+    dontBotherDOM = true;
+}
+
+hooks.main.onReady.add(function override(pyScript) {
     // be sure this override happens only once
-    hooks.onInterpreterReady.delete(override);
+    hooks.main.onReady.delete(override);
 
     // trap generic `stderr` to propagate to it regardless
     const { stderr } = pyScript.io;
 
-    // override it with our own logic
+    const cb = (error, ...rest) => {
-    pyScript.io.stderr = (error, ...rest) => {
         notify(error.message || error);
         // let other plugins or stderr hook, if any, do the rest
         return stderr(error, ...rest);
     };
 
+    // override it with our own logic
+    pyScript.io.stderr = pyScript.type === "py" ? cb : buffered(cb);
+
     // be sure uncaught Python errors are also visible
     addEventListener("error", ({ message }) => {
         if (message.startsWith("Uncaught PythonError")) notify(message);
@@ -30,6 +38,7 @@ hooks.onInterpreterReady.add(function override(pyScript) {
  * @param {string} message
  */
 export function notify(message) {
+    if (dontBotherDOM) return;
     const div = document.createElement("div");
     div.className = "py-error";
     div.textContent = message;

core/src/plugins/py-editor.js

@@ -0,0 +1,458 @@
+// PyScript py-editor plugin
+import { Hook, XWorker, dedent, defineProperties } from "polyscript/exports";
+import { TYPES, offline_interpreter, relative_url, stdlib } from "../core.js";
+import { notify } from "./error.js";
+import codemirror from "./codemirror.js";
+
+const RUN_BUTTON = `<svg style="height:24px;width:24px" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M19,12a1,1,0,0,1-.55.89l-10,5A1,1,0,0,1,8,18a1,1,0,0,1-.53-.15A1,1,0,0,1,7,17V7a1,1,0,0,1,1.45-.89l10,5A1,1,0,0,1,19,12Z" fill="#464646"/></svg>`;
+const STOP_BUTTON = `<svg style="height:24px;width:24px" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M7 7h10v10H7z" style="fill:#464646;stroke:#464646;stroke-width:1;stroke-linecap:butt;stroke-linejoin:round;stroke-dasharray:none;paint-order:normal"/></svg>`;
+
+let id = 0;
+const getID = (type) => `${type}-editor-${id++}`;
+
+const envs = new Map();
+const configs = new Map();
+const editors = new WeakMap();
+
+const hooks = {
+    worker: {
+        codeBeforeRun: () => stdlib,
+        // works on both Pyodide and MicroPython
+        onReady: ({ runAsync, io }, { sync }) => {
+            io.stdout = io.buffered(sync.write);
+            io.stderr = io.buffered(sync.writeErr);
+            sync.revoke();
+            sync.runAsync = runAsync;
+        },
+    },
+};
+
+const validate = (config, result) => {
+    if (typeof result === "boolean") throw `Invalid source: ${config}`;
+    return result;
+};
+
+const getRelatedScript = (target, type) => {
+    const editor = target.closest(`.${type}-editor-box`);
+    return editor?.parentNode?.previousElementSibling;
+};
+
+async function execute({ currentTarget }) {
+    const { env, pySrc, outDiv } = this;
+    const hasRunButton = !!currentTarget;
+
+    if (hasRunButton) {
+        currentTarget.classList.add("running");
+        currentTarget.innerHTML = STOP_BUTTON;
+        outDiv.innerHTML = "";
+    }
+
+    if (!envs.has(env)) {
+        const srcLink = URL.createObjectURL(new Blob([""]));
+        const details = {
+            type: this.interpreter,
+            serviceWorker: this.serviceWorker,
+        };
+        const { config } = this;
+        if (config) {
+            // verify that config can be parsed and used
+            try {
+                details.configURL = relative_url(config);
+                if (config.endsWith(".toml")) {
+                    const [{ parse }, toml] = await Promise.all([
+                        import(
+                            /* webpackIgnore: true */ "../3rd-party/toml.js"
+                        ),
+                        fetch(config).then((r) => r.ok && r.text()),
+                    ]);
+                    details.config = parse(validate(config, toml));
+                } else if (config.endsWith(".json")) {
+                    const json = await fetch(config).then(
+                        (r) => r.ok && r.json(),
+                    );
+                    details.config = validate(config, json);
+                } else {
+                    details.configURL = relative_url("./config.txt");
+                    details.config = JSON.parse(config);
+                }
+                details.version = offline_interpreter(details.config);
+            } catch (error) {
+                notify(error);
+                return;
+            }
+        } else {
+            details.config = {};
+        }
+
+        const xworker = XWorker.call(new Hook(null, hooks), srcLink, details);
+
+        // expose xworker like in terminal or other workers to allow
+        // creation and destruction of editors on the fly
+        if (hasRunButton) {
+            for (const type of TYPES.keys()) {
+                const script = getRelatedScript(currentTarget, type);
+                if (script) {
+                    defineProperties(script, { xworker: { value: xworker } });
+                    break;
+                }
+            }
+        }
+
+        const { sync } = xworker;
+        const { promise, resolve } = Promise.withResolvers();
+        envs.set(env, promise);
+        sync.revoke = () => {
+            URL.revokeObjectURL(srcLink);
+            resolve(xworker);
+        };
+    }
+
+    // wait for the env then set the target div
+    // before executing the current code
+    return envs.get(env).then((xworker) => {
+        xworker.onerror = ({ error }) => {
+            if (hasRunButton) {
+                outDiv.insertAdjacentHTML(
+                    "beforeend",
+                    `<span style='color:red'>${
+                        error.message || error
+                    }</span>\n`,
+                );
+            }
+            console.error(error);
+        };
+
+        const enable = () => {
+            if (hasRunButton) {
+                currentTarget.classList.remove("running");
+                currentTarget.innerHTML = RUN_BUTTON;
+            }
+        };
+        const { sync } = xworker;
+        sync.write = (str) => {
+            if (hasRunButton) outDiv.innerText += `${str}\n`;
+            else console.log(str);
+        };
+        sync.writeErr = (str) => {
+            if (hasRunButton) {
+                outDiv.insertAdjacentHTML(
+                    "beforeend",
+                    `<span style='color:red'>${str}</span>\n`,
+                );
+            } else {
+                notify(str);
+                console.error(str);
+            }
+        };
+        sync.runAsync(pySrc).then(enable, enable);
+    });
+}
+
+const makeRunButton = (handler, type) => {
+    const runButton = document.createElement("button");
+    runButton.className = `absolute ${type}-editor-run-button`;
+    runButton.innerHTML = RUN_BUTTON;
+    runButton.setAttribute("aria-label", "Python Script Run Button");
+    runButton.addEventListener("click", async (event) => {
+        if (
+            runButton.classList.contains("running") &&
+            confirm("Stop evaluating this code?")
+        ) {
+            const script = getRelatedScript(runButton, type);
+            if (script) {
+                const editor = editors.get(script);
+                const content = editor.state.doc.toString();
+                const clone = script.cloneNode(true);
+                clone.type = `${type}-editor`;
+                clone.textContent = content;
+                script.xworker.terminate();
+                script.nextElementSibling.remove();
+                script.replaceWith(clone);
+                editors.delete(script);
+            }
+            return;
+        }
+        runButton.blur();
+        await handler.handleEvent(event);
+    });
+    return runButton;
+};
+
+const makeEditorDiv = (handler, type) => {
+    const editorDiv = document.createElement("div");
+    editorDiv.className = `${type}-editor-input`;
+    editorDiv.setAttribute("aria-label", "Python Script Area");
+
+    const runButton = makeRunButton(handler, type);
+    const editorShadowContainer = document.createElement("div");
+
+    // avoid outer elements intercepting key events (reveal as example)
+    editorShadowContainer.addEventListener("keydown", (event) => {
+        event.stopPropagation();
+    });
+
+    editorDiv.append(runButton, editorShadowContainer);
+
+    return editorDiv;
+};
+
+const makeOutDiv = (type) => {
+    const outDiv = document.createElement("div");
+    outDiv.className = `${type}-editor-output`;
+    outDiv.id = `${getID(type)}-output`;
+    return outDiv;
+};
+
+const makeBoxDiv = (handler, type) => {
+    const boxDiv = document.createElement("div");
+    boxDiv.className = `${type}-editor-box`;
+
+    const editorDiv = makeEditorDiv(handler, type);
+    const outDiv = makeOutDiv(type);
+    boxDiv.append(editorDiv, outDiv);
+
+    return [boxDiv, outDiv, editorDiv.querySelector("button")];
+};
+
+const init = async (script, type, interpreter) => {
+    const [
+        { basicSetup, EditorView },
+        { Compartment },
+        { python },
+        { indentUnit },
+        { keymap },
+        { defaultKeymap, indentWithTab },
+    ] = await Promise.all([
+        codemirror.core,
+        codemirror.state,
+        codemirror.python,
+        codemirror.language,
+        codemirror.view,
+        codemirror.commands,
+    ]);
+
+    let isSetup = script.hasAttribute("setup");
+    const hasConfig = script.hasAttribute("config");
+    const serviceWorker = script.getAttribute("service-worker");
+    const env = `${interpreter}-${script.getAttribute("env") || getID(type)}`;
+
+    // helps preventing too lazy ServiceWorker initialization on button run
+    if (serviceWorker) {
+        new XWorker("data:application/javascript,postMessage(0)", {
+            type: "dummy",
+            serviceWorker,
+        }).onmessage = ({ target }) => target.terminate();
+    }
+
+    if (hasConfig && configs.has(env)) {
+        throw new SyntaxError(
+            configs.get(env)
+                ? `duplicated config for env: ${env}`
+                : `unable to add a config to the env: ${env}`,
+        );
+    }
+
+    configs.set(env, hasConfig);
+
+    let source = script.textContent;
+
+    // verify the src points to a valid file that can be parsed
+    const { src } = script;
+    if (src) {
+        try {
+            source = validate(
+                src,
+                await fetch(src).then((b) => b.ok && b.text()),
+            );
+        } catch (error) {
+            notify(error);
+            return;
+        }
+    }
+
+    const context = {
+        // allow the listener to be overridden at distance
+        handleEvent: execute,
+        serviceWorker,
+        interpreter,
+        env,
+        config: hasConfig && script.getAttribute("config"),
+        get pySrc() {
+            return isSetup ? source : editor.state.doc.toString();
+        },
+        get outDiv() {
+            return isSetup ? null : outDiv;
+        },
+    };
+
+    let target;
+    defineProperties(script, {
+        target: { get: () => target },
+        handleEvent: {
+            get: () => context.handleEvent,
+            set: (callback) => {
+                // do not bother with logic if it was set back as its original handler
+                if (callback === execute) context.handleEvent = execute;
+                // in every other case be sure that if the listener override returned
+                // `false` nothing happens, otherwise keep doing what it always did
+                else {
+                    context.handleEvent = async (event) => {
+                        // trap the currentTarget ASAP (if any)
+                        // otherwise it gets lost asynchronously
+                        const { currentTarget } = event;
+                        // augment a code snapshot before invoking the override
+                        defineProperties(event, {
+                            code: { value: context.pySrc },
+                        });
+                        // avoid executing the default handler if the override returned `false`
+                        if ((await callback(event)) !== false)
+                            await execute.call(context, { currentTarget });
+                    };
+                }
+            },
+        },
+        code: {
+            get: () => context.pySrc,
+            set: (insert) => {
+                if (isSetup) return;
+                editor.update([
+                    editor.state.update({
+                        changes: {
+                            from: 0,
+                            to: editor.state.doc.length,
+                            insert,
+                        },
+                    }),
+                ]);
+            },
+        },
+        process: {
+            /**
+             * Simulate a setup node overriding the source to evaluate.
+             * @param {string} code the Python code to evaluate.
+             * @param {boolean} asRunButtonAction invoke the `Run` button handler.
+             * @returns {Promise<...>} fulfill once code has been evaluated.
+             */
+            value(code, asRunButtonAction = false) {
+                if (asRunButtonAction) return listener();
+                const wasSetup = isSetup;
+                const wasSource = source;
+                isSetup = true;
+                source = code;
+                const restore = () => {
+                    isSetup = wasSetup;
+                    source = wasSource;
+                };
+                return context
+                    .handleEvent({ currentTarget: null })
+                    .then(restore, restore);
+            },
+        },
+    });
+
+    const notifyEditor = () => {
+        const event = new Event(`${type}-editor`, { bubbles: true });
+        script.dispatchEvent(event);
+    };
+
+    if (isSetup) {
+        await context.handleEvent({ currentTarget: null });
+        notifyEditor();
+        return;
+    }
+
+    const selector = script.getAttribute("target");
+
+    if (selector) {
+        target =
+            document.getElementById(selector) ||
+            document.querySelector(selector);
+        if (!target) throw new Error(`Unknown target ${selector}`);
+    } else {
+        target = document.createElement(`${type}-editor`);
+        target.style.display = "block";
+        script.after(target);
+    }
+
+    if (!target.id) target.id = getID(type);
+    if (!target.hasAttribute("exec-id")) target.setAttribute("exec-id", 0);
+    if (!target.hasAttribute("root")) target.setAttribute("root", target.id);
+
+    // @see https://github.com/JeffersGlass/mkdocs-pyscript/blob/main/mkdocs_pyscript/js/makeblocks.js
+    const [boxDiv, outDiv, runButton] = makeBoxDiv(context, type);
+    boxDiv.dataset.env = script.hasAttribute("env") ? env : interpreter;
+
+    const inputChild = boxDiv.querySelector(`.${type}-editor-input > div`);
+    const parent = inputChild.attachShadow({ mode: "open" });
+    // avoid inheriting styles from the outer component
+    parent.innerHTML = `<style> :host { all: initial; }</style>`;
+
+    target.appendChild(boxDiv);
+
+    const doc = dedent(script.textContent).trim();
+
+    // preserve user indentation, if any
+    const indentation = /^([ \t]+)/m.test(doc) ? RegExp.$1 : "    ";
+
+    const listener = () => runButton.click();
+    const editor = new EditorView({
+        extensions: [
+            indentUnit.of(indentation),
+            new Compartment().of(python()),
+            keymap.of([
+                ...defaultKeymap,
+                { key: "Ctrl-Enter", run: listener, preventDefault: true },
+                { key: "Cmd-Enter", run: listener, preventDefault: true },
+                { key: "Shift-Enter", run: listener, preventDefault: true },
+                // @see https://codemirror.net/examples/tab/
+                indentWithTab,
+            ]),
+            basicSetup,
+        ],
+        foldGutter: true,
+        gutters: ["CodeMirror-linenumbers", "CodeMirror-foldgutter"],
+        parent,
+        doc,
+    });
+
+    editors.set(script, editor);
+    editor.focus();
+    notifyEditor();
+};
+
+// avoid too greedy MutationObserver operations at distance
+let timeout = 0;
+
+// avoid delayed initialization
+let queue = Promise.resolve();
+
+// reset interval value then check for new scripts
+const resetTimeout = () => {
+    timeout = 0;
+    pyEditor();
+};
+
+// triggered both ASAP on the living DOM and via MutationObserver later
+const pyEditor = () => {
+    if (timeout) return;
+    timeout = setTimeout(resetTimeout, 250);
+    for (const [type, interpreter] of TYPES) {
+        const selector = `script[type="${type}-editor"]`;
+        for (const script of document.querySelectorAll(selector)) {
+            // avoid any further bootstrap by changing the type as active
+            script.type += "-active";
+            // don't await in here or multiple calls might happen
+            // while the first script is being initialized
+            queue = queue.then(() => init(script, type, interpreter));
+        }
+    }
+    return queue;
+};
+
+new MutationObserver(pyEditor).observe(document, {
+    childList: true,
+    subtree: true,
+});
+
+// try to check the current document ASAP
+export default pyEditor();

core/src/plugins/py-game.js

@@ -0,0 +1,112 @@
+import {
+    dedent,
+    define,
+    createProgress,
+    loadProgress,
+} from "polyscript/exports";
+
+import { stdlib } from "../core.js";
+import { configDetails } from "../config.js";
+import { getText } from "../fetch.js";
+
+const progress = createProgress("py-game");
+
+const inputPatch = `
+import builtins
+def input(prompt=""):
+    import js
+    return js.prompt(prompt)
+
+builtins.input = input
+del builtins
+del input
+`;
+
+let toBeWarned = true;
+
+const hooks = {
+    main: {
+        onReady: async (wrap, script) => {
+            if (toBeWarned) {
+                toBeWarned = false;
+                console.warn("⚠️ EXPERIMENTAL `py-game` FEATURE");
+            }
+
+            let config = {};
+            if (script.hasAttribute("config")) {
+                const value = script.getAttribute("config");
+                const { json, toml, text, url } = await configDetails(value);
+                if (json) config = JSON.parse(text);
+                else if (toml) {
+                    const { parse } = await import(
+                        /* webpackIgnore: true */ "../3rd-party/toml.js"
+                    );
+                    config = parse(text);
+                }
+                if (config.packages) {
+                    await wrap.interpreter.loadPackage("micropip");
+                    const micropip = wrap.interpreter.pyimport("micropip");
+                    await micropip.install(config.packages, {
+                        keep_going: true,
+                    });
+                    micropip.destroy();
+                }
+                await loadProgress(
+                    "py-game",
+                    progress,
+                    wrap.interpreter,
+                    config,
+                    url ? new URL(url, location.href).href : location.href,
+                );
+            }
+
+            wrap.interpreter.registerJsModule("_pyscript", {
+                PyWorker() {
+                    throw new Error(
+                        "Unable to use PyWorker in py-game scripts",
+                    );
+                },
+                js_import: (...urls) =>
+                    Promise.all(urls.map((url) => import(url))),
+                get target() {
+                    return script.id;
+                },
+            });
+
+            await wrap.interpreter.runPythonAsync(stdlib);
+            wrap.interpreter.runPython(inputPatch);
+
+            let code = dedent(script.textContent);
+            if (script.src) code = await fetch(script.src).then(getText);
+
+            const target = script.getAttribute("target") || "canvas";
+            const canvas = document.getElementById(target);
+            wrap.interpreter.canvas.setCanvas2D(canvas);
+
+            // allow 3rd party to hook themselves right before
+            // the code gets executed
+            const event = new CustomEvent("py-game", {
+                bubbles: true,
+                cancelable: true,
+                detail: {
+                    canvas,
+                    code,
+                    config,
+                    wrap,
+                },
+            });
+            script.dispatchEvent(event);
+            // run only if the default was not prevented
+            if (!event.defaultPrevented)
+                await wrap.interpreter.runPythonAsync(code);
+        },
+    },
+};
+
+define("py-game", {
+    config: { packages: ["pygame-ce"] },
+    configURL: new URL("./config.txt", location.href).href,
+    interpreter: "pyodide",
+    env: "py-game",
+    hooks,
+});

core/src/plugins/py-terminal.js

@@ -0,0 +1,60 @@
+// PyScript py-terminal plugin
+import { TYPES, relative_url } from "../core.js";
+import { notify } from "./error.js";
+import { customObserver } from "polyscript/exports";
+
+// will contain all valid selectors
+const SELECTORS = [];
+
+// avoid processing same elements twice
+const processed = new WeakSet();
+
+// show the error on main and
+// stops the module from keep executing
+const notifyAndThrow = (message) => {
+    notify(message);
+    throw new Error(message);
+};
+
+const onceOnMain = ({ attributes: { worker } }) => !worker;
+
+let addStyle = true;
+
+for (const type of TYPES.keys()) {
+    const selector = `script[type="${type}"][terminal],${type}-script[terminal]`;
+    SELECTORS.push(selector);
+    customObserver.set(selector, async (element) => {
+        // we currently support only one terminal on main as in "classic"
+        const terminals = document.querySelectorAll(SELECTORS.join(","));
+        if ([].filter.call(terminals, onceOnMain).length > 1)
+            notifyAndThrow("You can use at most 1 main terminal");
+
+        // import styles lazily
+        if (addStyle) {
+            addStyle = false;
+            document.head.append(
+                Object.assign(document.createElement("link"), {
+                    rel: "stylesheet",
+                    href: relative_url("./xterm.css", import.meta.url),
+                }),
+            );
+        }
+
+        if (processed.has(element)) return;
+        processed.add(element);
+
+        const bootstrap = (module) => module.default(element);
+
+        // we can't be smart with template literals for the dynamic import
+        // or bundlers are incapable of producing multiple files around
+        if (type === "mpy") {
+            await import(/* webpackIgnore: true */ "./py-terminal/mpy.js").then(
+                bootstrap,
+            );
+        } else {
+            await import(/* webpackIgnore: true */ "./py-terminal/py.js").then(
+                bootstrap,
+            );
+        }
+    });
+}

core/src/plugins/py-terminal/mpy.js

@@ -0,0 +1,255 @@
+// PyScript pyodide terminal plugin
+import { defineProperties } from "polyscript/exports";
+import { hooks, inputFailure } from "../../core.js";
+
+const bootstrapped = new WeakSet();
+
+// this callback will be serialized as string and it never needs
+// to be invoked multiple times. Each xworker here is bootstrapped
+// only once thanks to the `sync.is_pyterminal()` check.
+const workerReady = ({ interpreter, io, run, type }, { sync }) => {
+    if (type !== "mpy" || !sync.is_pyterminal()) return;
+
+    const { pyterminal_ready, pyterminal_read, pyterminal_write } = sync;
+
+    interpreter.registerJsModule("_pyscript_input", {
+        input: pyterminal_read,
+    });
+
+    run(
+        [
+            "from _pyscript_input import input",
+            "from polyscript import currentScript as _",
+            "__terminal__ = _.terminal",
+            "del _",
+        ].join(";"),
+    );
+
+    const missingReturn = new Uint8Array([13]);
+    io.stdout = (buffer) => {
+        if (buffer[0] === 10) pyterminal_write(missingReturn);
+        pyterminal_write(buffer);
+    };
+    io.stderr = (error) => {
+        pyterminal_write(String(error.message || error));
+    };
+
+    sync.pyterminal_stream_write = () => {};
+
+    // tiny shim of the code module with only interact
+    // to bootstrap a REPL like environment
+    interpreter.registerJsModule("code", {
+        interact() {
+            const encoder = new TextEncoderStream();
+            encoder.readable.pipeTo(
+                new WritableStream({
+                    write(buffer) {
+                        for (const c of buffer) interpreter.replProcessChar(c);
+                    },
+                }),
+            );
+
+            const writer = encoder.writable.getWriter();
+            sync.pyterminal_stream_write = (buffer) => writer.write(buffer);
+
+            interpreter.replInit();
+        },
+    });
+
+    pyterminal_ready();
+};
+
+export default async (element) => {
+    // lazy load these only when a valid terminal is found
+    const [{ Terminal }, { FitAddon }, { WebLinksAddon }] = await Promise.all([
+        import(/* webpackIgnore: true */ "../../3rd-party/xterm.js"),
+        import(/* webpackIgnore: true */ "../../3rd-party/xterm_addon-fit.js"),
+        import(
+            /* webpackIgnore: true */ "../../3rd-party/xterm_addon-web-links.js"
+        ),
+    ]);
+
+    const terminalOptions = {
+        disableStdin: false,
+        cursorBlink: true,
+        cursorStyle: "block",
+        lineHeight: 1.2,
+    };
+
+    let stream;
+
+    // common main thread initialization for both worker
+    // or main case, bootstrapping the terminal on its target
+    const init = () => {
+        let target = element;
+        const selector = element.getAttribute("target");
+        if (selector) {
+            target =
+                document.getElementById(selector) ||
+                document.querySelector(selector);
+            if (!target) throw new Error(`Unknown target ${selector}`);
+        } else {
+            target = document.createElement("py-terminal");
+            target.style.display = "block";
+            element.after(target);
+        }
+        const terminal = new Terminal({
+            theme: {
+                background: "#191A19",
+                foreground: "#F5F2E7",
+            },
+            ...terminalOptions,
+        });
+        const fitAddon = new FitAddon();
+        terminal.loadAddon(fitAddon);
+        terminal.loadAddon(new WebLinksAddon());
+        terminal.open(target);
+        fitAddon.fit();
+        terminal.focus();
+        defineProperties(element, {
+            terminal: { value: terminal },
+            process: {
+                value: async (code) => {
+                    for (const line of code.split(/(?:\r\n|\r|\n)/)) {
+                        await stream.write(`${line}\r`);
+                    }
+                },
+            },
+        });
+        return terminal;
+    };
+
+    // branch logic for the worker
+    if (element.hasAttribute("worker")) {
+        // add a hook on the main thread to setup all sync helpers
+        // also bootstrapping the XTerm target on main *BUT* ...
+        hooks.main.onWorker.add(function worker(_, xworker) {
+            // ... as multiple workers will add multiple callbacks
+            // be sure no xworker is ever initialized twice!
+            if (bootstrapped.has(xworker)) return;
+            bootstrapped.add(xworker);
+
+            // still cleanup this callback for future scripts/workers
+            hooks.main.onWorker.delete(worker);
+
+            const terminal = init();
+
+            const { sync } = xworker;
+
+            // handle the read mode on input
+            let promisedChunks = null;
+            let readChunks = "";
+
+            sync.is_pyterminal = () => true;
+
+            // put the terminal in a read-only state
+            // frees the worker on \r
+            sync.pyterminal_read = (buffer) => {
+                terminal.write(buffer);
+                promisedChunks = Promise.withResolvers();
+                return promisedChunks.promise;
+            };
+
+            // write if not reading input
+            sync.pyterminal_write = (buffer) => {
+                if (!promisedChunks) terminal.write(buffer);
+            };
+
+            // add the onData terminal listener which forwards to the worker
+            // everything typed in a queued char-by-char way
+            sync.pyterminal_ready = () => {
+                let queue = Promise.resolve();
+                stream = {
+                    write: (buffer) =>
+                        (queue = queue.then(() =>
+                            sync.pyterminal_stream_write(buffer),
+                        )),
+                };
+                terminal.onData((buffer) => {
+                    if (promisedChunks) {
+                        // handle backspace on input
+                        if (buffer === "\x7f") {
+                            // avoid over-greedy backspace
+                            if (readChunks.length) {
+                                readChunks = readChunks.slice(0, -1);
+                                // override previous char position
+                                // put an empty space to clear the char
+                                // move back position again
+                                buffer = "\b \b";
+                            } else buffer = "";
+                        } else readChunks += buffer;
+                        if (buffer) {
+                            terminal.write(buffer);
+                            if (readChunks.endsWith("\r")) {
+                                terminal.write("\n");
+                                promisedChunks.resolve(readChunks.slice(0, -1));
+                                promisedChunks = null;
+                                readChunks = "";
+                            }
+                        }
+                    } else {
+                        stream.write(buffer);
+                    }
+                });
+            };
+        });
+
+        // setup remote thread JS/Python code for whenever the
+        // worker is ready to become a terminal
+        hooks.worker.onReady.add(workerReady);
+    } else {
+        // ⚠️ In an ideal world the inputFailure should never be used on main.
+        //    However, Pyodide still can't compete with MicroPython REPL mode
+        //    so while it's OK to keep that entry on main as default, we need
+        //    to remove it ASAP from `mpy` use cases, otherwise MicroPython would
+        //    also throw whenever an `input(...)` is required / digited.
+        hooks.main.codeBeforeRun.delete(inputFailure);
+
+        // in the main case, just bootstrap XTerm without
+        // allowing any input as that's not possible / awkward
+        hooks.main.onReady.add(function main({ interpreter, io, run, type }) {
+            if (type !== "mpy") return;
+
+            hooks.main.onReady.delete(main);
+
+            const terminal = init();
+
+            const missingReturn = new Uint8Array([13]);
+            io.stdout = (buffer) => {
+                if (buffer[0] === 10) terminal.write(missingReturn);
+                terminal.write(buffer);
+            };
+
+            // expose the __terminal__ one-off reference
+            globalThis.__py_terminal__ = terminal;
+            run(
+                [
+                    "from js import prompt as input",
+                    "from js import __py_terminal__ as __terminal__",
+                ].join(";"),
+            );
+            delete globalThis.__py_terminal__;
+
+            // NOTE: this is NOT the same as the one within
+            //       the onWorkerReady callback!
+            interpreter.registerJsModule("code", {
+                interact() {
+                    const encoder = new TextEncoderStream();
+                    encoder.readable.pipeTo(
+                        new WritableStream({
+                            write(buffer) {
+                                for (const c of buffer)
+                                    interpreter.replProcessChar(c);
+                            },
+                        }),
+                    );
+
+                    stream = encoder.writable.getWriter();
+                    terminal.onData((buffer) => stream.write(buffer));
+
+                    interpreter.replInit();
+                },
+            });
+        });
+    }
+};

core/src/plugins/py-terminal/py.js

@@ -0,0 +1,192 @@
+// PyScript py-terminal plugin
+import { defineProperties } from "polyscript/exports";
+import { hooks } from "../../core.js";
+
+const bootstrapped = new WeakSet();
+
+// this callback will be serialized as string and it never needs
+// to be invoked multiple times. Each xworker here is bootstrapped
+// only once thanks to the `sync.is_pyterminal()` check.
+const workerReady = ({ interpreter, io, run, type }, { sync }) => {
+    if (type !== "py" || !sync.is_pyterminal()) return;
+
+    run(
+        [
+            "from polyscript import currentScript as _",
+            "__terminal__ = _.terminal",
+            "del _",
+        ].join(";"),
+    );
+
+    let data = "";
+    const { pyterminal_read, pyterminal_write } = sync;
+    const decoder = new TextDecoder();
+    const generic = {
+        isatty: false,
+        write(buffer) {
+            data = decoder.decode(buffer);
+            pyterminal_write(data);
+            return buffer.length;
+        },
+    };
+
+    io.stderr = (error) => {
+        pyterminal_write(String(error.message || error));
+    };
+
+    interpreter.setStdout(generic);
+    interpreter.setStderr(generic);
+    interpreter.setStdin({
+        isatty: false,
+        stdin: () => pyterminal_read(data),
+    });
+};
+
+export default async (element) => {
+    // lazy load these only when a valid terminal is found
+    const [{ Terminal }, { Readline }, { FitAddon }, { WebLinksAddon }] =
+        await Promise.all([
+            import(/* webpackIgnore: true */ "../../3rd-party/xterm.js"),
+            import(
+                /* webpackIgnore: true */ "../../3rd-party/xterm-readline.js"
+            ),
+            import(
+                /* webpackIgnore: true */ "../../3rd-party/xterm_addon-fit.js"
+            ),
+            import(
+                /* webpackIgnore: true */ "../../3rd-party/xterm_addon-web-links.js"
+            ),
+        ]);
+
+    const readline = new Readline();
+
+    // common main thread initialization for both worker
+    // or main case, bootstrapping the terminal on its target
+    const init = (options) => {
+        let target = element;
+        const selector = element.getAttribute("target");
+        if (selector) {
+            target =
+                document.getElementById(selector) ||
+                document.querySelector(selector);
+            if (!target) throw new Error(`Unknown target ${selector}`);
+        } else {
+            target = document.createElement("py-terminal");
+            target.style.display = "block";
+            element.after(target);
+        }
+        const terminal = new Terminal({
+            theme: {
+                background: "#191A19",
+                foreground: "#F5F2E7",
+            },
+            ...options,
+        });
+        const fitAddon = new FitAddon();
+        terminal.loadAddon(fitAddon);
+        terminal.loadAddon(readline);
+        terminal.loadAddon(new WebLinksAddon());
+        terminal.open(target);
+        fitAddon.fit();
+        terminal.focus();
+        defineProperties(element, {
+            terminal: { value: terminal },
+            process: {
+                value: async (code) => {
+                    for (const line of code.split(/(?:\r\n|\r|\n)/)) {
+                        terminal.paste(`${line}`);
+                        terminal.write("\r\n");
+                        do {
+                            await new Promise((resolve) =>
+                                setTimeout(resolve, 0),
+                            );
+                        } while (!readline.activeRead?.resolve);
+                        readline.activeRead.resolve(line);
+                    }
+                },
+            },
+        });
+        return terminal;
+    };
+
+    // branch logic for the worker
+    if (element.hasAttribute("worker")) {
+        // add a hook on the main thread to setup all sync helpers
+        // also bootstrapping the XTerm target on main *BUT* ...
+        hooks.main.onWorker.add(function worker(_, xworker) {
+            // ... as multiple workers will add multiple callbacks
+            // be sure no xworker is ever initialized twice!
+            if (bootstrapped.has(xworker)) return;
+            bootstrapped.add(xworker);
+
+            // still cleanup this callback for future scripts/workers
+            hooks.main.onWorker.delete(worker);
+
+            init({
+                disableStdin: false,
+                cursorBlink: true,
+                cursorStyle: "block",
+                lineHeight: 1.2,
+            });
+
+            xworker.sync.is_pyterminal = () => true;
+            xworker.sync.pyterminal_read = readline.read.bind(readline);
+            xworker.sync.pyterminal_write = readline.write.bind(readline);
+        });
+
+        // setup remote thread JS/Python code for whenever the
+        // worker is ready to become a terminal
+        hooks.worker.onReady.add(workerReady);
+
+        // @see https://github.com/pyscript/pyscript/issues/2246
+        const patchInput = [
+            "import builtins as _b",
+            "from pyscript import sync as _s",
+            "_b.input = _s.pyterminal_read",
+            "del _b",
+            "del _s",
+        ].join("\n");
+
+        hooks.worker.codeBeforeRun.add(patchInput);
+        hooks.worker.codeBeforeRunAsync.add(patchInput);
+    } else {
+        // in the main case, just bootstrap XTerm without
+        // allowing any input as that's not possible / awkward
+        hooks.main.onReady.add(function main({ interpreter, io, run, type }) {
+            if (type !== "py") return;
+
+            console.warn("py-terminal is read only on main thread");
+            hooks.main.onReady.delete(main);
+
+            // on main, it's easy to trash and clean the current terminal
+            globalThis.__py_terminal__ = init({
+                disableStdin: true,
+                cursorBlink: false,
+                cursorStyle: "underline",
+            });
+            run("from js import __py_terminal__ as __terminal__");
+            delete globalThis.__py_terminal__;
+
+            io.stderr = (error) => {
+                readline.write(String(error.message || error));
+            };
+
+            let data = "";
+            const decoder = new TextDecoder();
+            const generic = {
+                isatty: false,
+                write(buffer) {
+                    data = decoder.decode(buffer);
+                    readline.write(data);
+                    return buffer.length;
+                },
+            };
+            interpreter.setStdout(generic);
+            interpreter.setStderr(generic);
+            interpreter.setStdin({
+                isatty: false,
+                stdin: () => readline.read(data),
+            });
+        });
+    }
+};

core/src/stdlib.js

@@ -0,0 +1,70 @@
+/**
+ * Create through Python the pyscript module through
+ * the artifact generated at build time.
+ * This the returned value is a string that must be used
+ * either before a worker execute code or when the module
+ * is registered on the main thread.
+ */
+
+import pyscript from "./stdlib/pyscript.js";
+
+class Ignore extends Array {
+    #add = false;
+    #paths;
+    #array;
+    constructor(array, ...paths) {
+        super();
+        this.#array = array;
+        this.#paths = paths;
+    }
+    push(...values) {
+        if (this.#add) super.push(...values);
+        return this.#array.push(...values);
+    }
+    path(path) {
+        for (const _path of this.#paths) {
+            // bails out at the first `true` value
+            if ((this.#add = path.startsWith(_path))) break;
+        }
+    }
+}
+
+const { entries } = Object;
+
+const python = [
+    "import os as _os",
+    "from pathlib import Path as _Path",
+    "_path = None",
+];
+
+const ignore = new Ignore(python, "-");
+
+const write = (base, literal) => {
+    for (const [key, value] of entries(literal)) {
+        ignore.path(`${base}/${key}`);
+        ignore.push(`_path = _Path("${base}/${key}")`);
+        if (typeof value === "string") {
+            const code = JSON.stringify(value);
+            ignore.push(`_path.write_text(${code},encoding="utf-8")`);
+        } else {
+            // @see https://github.com/pyscript/pyscript/pull/1813#issuecomment-1781502909
+            ignore.push(`if not _os.path.exists("${base}/${key}"):`);
+            ignore.push("    _path.mkdir(parents=True, exist_ok=True)");
+            write(`${base}/${key}`, value);
+        }
+    }
+};
+
+write(".", pyscript);
+
+// in order to fix js.document in the Worker case
+// we need to bootstrap pyscript module ASAP
+python.push("import pyscript as _pyscript");
+
+python.push(
+    ...["_Path", "_path", "_os", "_pyscript"].map((ref) => `del ${ref}`),
+);
+python.push("\n");
+
+export const stdlib = python.join("\n");
+export const optional = ignore.join("\n");

core/src/stdlib/pyscript/__init__.py

@@ -29,21 +29,23 @@
 #     pyscript.magic_js. This is the blessed way to access them from pyscript,
 #     as it works transparently in both the main thread and worker cases.
 
-from pyscript.display import HTML, display
+from polyscript import lazy_py_modules as py_import
 from pyscript.magic_js import (
     RUNNING_IN_WORKER,
     PyWorker,
+    config,
     current_target,
     document,
+    js_import,
+    js_modules,
     sync,
     window,
 )
+from pyscript.display import HTML, display
+from pyscript.fetch import fetch
+from pyscript.storage import Storage, storage
+from pyscript.websocket import WebSocket
+from pyscript.events import when, Event
 
-try:
+if not RUNNING_IN_WORKER:
-    from pyscript.event_handling import when
+    from pyscript.workers import create_named_worker, workers
-except:
-    from pyscript.util import NotSupported
-
-    when = NotSupported(
-        "pyscript.when", "pyscript.when currently not available with this interpreter"
-    )

core/src/stdlib/pyscript/display.py

@@ -6,17 +6,17 @@ import re
 from pyscript.magic_js import current_target, document, window
 
 _MIME_METHODS = {
-    "__repr__": "text/plain",
-    "_repr_html_": "text/html",
-    "_repr_markdown_": "text/markdown",
-    "_repr_svg_": "image/svg+xml",
-    "_repr_pdf_": "application/pdf",
-    "_repr_jpeg_": "image/jpeg",
-    "_repr_png_": "image/png",
-    "_repr_latex": "text/latex",
-    "_repr_json_": "application/json",
-    "_repr_javascript_": "application/javascript",
     "savefig": "image/png",
+    "_repr_javascript_": "application/javascript",
+    "_repr_json_": "application/json",
+    "_repr_latex": "text/latex",
+    "_repr_png_": "image/png",
+    "_repr_jpeg_": "image/jpeg",
+    "_repr_pdf_": "application/pdf",
+    "_repr_svg_": "image/svg+xml",
+    "_repr_markdown_": "text/markdown",
+    "_repr_html_": "text/html",
+    "__repr__": "text/plain",
 }
 
 
@@ -73,14 +73,14 @@ def _eval_formatter(obj, print_method):
     """
     if print_method == "__repr__":
         return repr(obj)
-    elif hasattr(obj, print_method):
+    if hasattr(obj, print_method):
         if print_method == "savefig":
             buf = io.BytesIO()
             obj.savefig(buf, format="png")
             buf.seek(0)
             return base64.b64encode(buf.read()).decode("utf-8")
         return getattr(obj, print_method)()
-    elif print_method == "_repr_mimebundle_":
+    if print_method == "_repr_mimebundle_":
         return {}, {}
     return None
 
@@ -99,7 +99,7 @@ def _format_mime(obj):
         format_dict = mimebundle
 
     output, not_available = None, []
-    for method, mime_type in reversed(_MIME_METHODS.items()):
+    for method, mime_type in _MIME_METHODS.items():
         if mime_type in format_dict:
             output = format_dict[mime_type]
         else:
@@ -107,7 +107,7 @@ def _format_mime(obj):
 
         if output is None:
             continue
-        elif mime_type not in _MIME_RENDERERS:
+        if mime_type not in _MIME_RENDERERS:
             not_available.append(mime_type)
             continue
         break
@@ -149,9 +149,11 @@ def display(*values, target=None, append=True):
     if target is None:
         target = current_target()
     elif not isinstance(target, str):
-        raise TypeError(f"target must be str or None, not {target.__class__.__name__}")
+        msg = f"target must be str or None, not {target.__class__.__name__}"
+        raise TypeError(msg)
     elif target == "":
-        raise ValueError("Cannot have an empty target")
+        msg = "Cannot have an empty target"
+        raise ValueError(msg)
     elif target.startswith("#"):
         # note: here target is str and not None!
         # align with @when behavior
@@ -161,9 +163,8 @@ def display(*values, target=None, append=True):
 
     # If target cannot be found on the page, a ValueError is raised
     if element is None:
-        raise ValueError(
+        msg = f"Invalid selector with id={target}. Cannot be found in the page."
-            f"Invalid selector with id={target}. Cannot be found in the page."
+        raise ValueError(msg)
-        )
 
     # if element is a <script type="py">, it has a 'target' attribute which
     # points to the visual element holding the displayed values. In that case,

core/src/stdlib/pyscript/events.py

@@ -0,0 +1,225 @@
+import asyncio
+import inspect
+
+from functools import wraps
+from pyscript.magic_js import document
+from pyscript.ffi import create_proxy
+from pyscript.util import is_awaitable
+from pyscript import config
+
+
+class Event:
+    """
+    Events represent something that may happen at some point in time (usually
+    the future). They're used to coordinate code when the timing of an event is
+    not known in advance (e.g. a button click or a network response).
+
+    An event is triggered with an arbitrary result. If no result is given, then
+    None is assumed as the result.
+
+    Add listener functions to the event, to be called with the result when the
+    event is triggered. The listener functions can be callable or awaitable. If
+    the listener is added several times, it will be called only once.
+
+    If the event was triggered before a listener is added, the listener will be
+    called as soon as it is added, with the result of the event.
+
+    If the event is never triggered, then its listeners will never be called.
+    It's also possible to remove listeners from the event.
+
+    If the result of the event is not available, a ValueError will be raised
+    when trying to access the result property. A RuntimeError will be raised if
+    the event is triggered more than once.
+    """
+
+    def __init__(self):
+        # To contain the listeners to be called when the event is triggered.
+        self._listeners = []
+        # The result associated with the event.
+        self._result = None
+        # A flag to indicate if the event has been triggered.
+        self._triggered = False
+
+    @property
+    def triggered(self):
+        """
+        A boolean flag to indicate if the event has been triggered.
+        """
+        return self._triggered
+
+    @property
+    def result(self):
+        """
+        The result of the event.
+        """
+        if self.triggered:
+            return self._result
+        msg = "Event has not been triggered yet. No result available."
+        raise ValueError(msg)
+
+    def trigger(self, result=None):
+        """
+        Trigger the event with an arbitrary result to pass into the listeners.
+        An event may only be triggered once (otherwise a RuntimeError is
+        raised).
+        """
+        if self.triggered:
+            msg = "Event has already been triggered."
+            raise RuntimeError(msg)
+        self._triggered = True
+        self._result = result
+        for listener in self._listeners:
+            self._call_listener(listener)
+
+    def add_listener(self, listener):
+        """
+        Add a callable/awaitable that listens for the result, when this event
+        is triggered.
+        """
+        if is_awaitable(listener) or callable(listener):
+            if listener not in self._listeners:
+                self._listeners.append(listener)
+                if self.triggered:
+                    # If the event was already triggered, call the listener
+                    # immediately with the result.
+                    self._call_listener(listener)
+        else:
+            msg = "Listener must be callable or awaitable."
+            raise ValueError(msg)
+
+    def remove_listener(self, *args):
+        """
+        Clear the specified listener functions in *args. If no listeners are
+        provided, clear all the listeners.
+        """
+        if args:
+            for listener in args:
+                self._listeners.remove(listener)
+        else:
+            self._listeners = []
+
+    def _call_listener(self, listener):
+        """
+        Call the referenced listener with the event's result.
+        """
+        if is_awaitable(listener):
+            asyncio.create_task(listener(self._result))
+        else:
+            listener(self._result)
+
+
+def when(target, *args, **kwargs):
+    """
+    Add an event listener to the target element(s) for the specified event type.
+
+    The target can be a string representing the event type, or an Event object.
+    If the target is an Event object, the event listener will be added to that
+    object. If the target is a string, the event listener will be added to the
+    element(s) that match the (second) selector argument.
+
+    If a (third) handler argument is provided, it will be called when the event
+    is triggered; thus allowing this to be used as both a function and a
+    decorator.
+    """
+    # If "when" is called as a function, try to grab the handler from the
+    # arguments. If there's no handler, this must be a decorator based call.
+    handler = None
+    if args and (callable(args[0]) or is_awaitable(args[0])):
+        handler = args[0]
+    elif callable(kwargs.get("handler")) or is_awaitable(kwargs.get("handler")):
+        handler = kwargs.pop("handler")
+    # If the target is a string, it is the "older" use of `when` where it
+    # represents the name of a DOM event.
+    if isinstance(target, str):
+        # Extract the selector from the arguments or keyword arguments.
+        selector = args[0] if args else kwargs.pop("selector")
+        if not selector:
+            msg = "No selector provided."
+            raise ValueError(msg)
+        # Grab the DOM elements to which the target event will be attached.
+        from pyscript.web import Element, ElementCollection
+
+        if isinstance(selector, str):
+            elements = document.querySelectorAll(selector)
+        elif isinstance(selector, Element):
+            elements = [selector._dom_element]
+        elif isinstance(selector, ElementCollection):
+            elements = [el._dom_element for el in selector]
+        else:
+            elements = selector if isinstance(selector, list) else [selector]
+
+    def decorator(func):
+        if config["type"] == "mpy":  # Is MicroPython?
+            if is_awaitable(func):
+
+                async def wrapper(*args, **kwargs):
+                    """
+                    This is  a very ugly hack to get micropython working because
+                    `inspect.signature` doesn't exist. It may be actually better
+                    to not try any magic for now and raise the error.
+                    """
+                    try:
+                        return await func(*args, **kwargs)
+
+                    except TypeError as e:
+                        if "takes" in str(e) and "positional arguments" in str(e):
+                            return await func()
+                        raise
+
+            else:
+
+                def wrapper(*args, **kwargs):
+                    """
+                    This is  a very ugly hack to get micropython working because
+                    `inspect.signature` doesn't exist. It may be actually better
+                    to not try any magic for now and raise the error.
+                    """
+                    try:
+                        return func(*args, **kwargs)
+
+                    except TypeError as e:
+                        if "takes" in str(e) and "positional arguments" in str(e):
+                            return func()
+                        raise
+
+        else:
+            sig = inspect.signature(func)
+            if sig.parameters:
+                if is_awaitable(func):
+
+                    async def wrapper(event):
+                        return await func(event)
+
+                else:
+                    wrapper = func
+            else:
+                # Function doesn't receive events.
+                if is_awaitable(func):
+
+                    async def wrapper(*args, **kwargs):
+                        return await func()
+
+                else:
+
+                    def wrapper(*args, **kwargs):
+                        return func()
+
+        wrapper = wraps(func)(wrapper)
+        if isinstance(target, Event):
+            # The target is a single Event object.
+            target.add_listener(wrapper)
+        elif isinstance(target, list) and all(isinstance(t, Event) for t in target):
+            # The target is a list of Event objects.
+            for evt in target:
+                evt.add_listener(wrapper)
+        else:
+            # The target is a string representing an event type, and so a
+            # DOM element or collection of elements is found in "elements".
+            for el in elements:
+                el.addEventListener(target, create_proxy(wrapper))
+        return wrapper
+
+    # If "when" was called as a decorator, return the decorator function,
+    # otherwise just call the internal decorator function with the supplied
+    # handler.
+    return decorator(handler) if handler else decorator

core/src/stdlib/pyscript/fetch.py

@@ -0,0 +1,87 @@
+import json
+
+import js
+from pyscript.util import as_bytearray
+
+
+### wrap the response to grant Pythonic results
+class _Response:
+    def __init__(self, response):
+        self._response = response
+
+    # grant access to response.ok and other fields
+    def __getattr__(self, attr):
+        return getattr(self._response, attr)
+
+    # exposed methods with Pythonic results
+    async def arrayBuffer(self):
+        buffer = await self._response.arrayBuffer()
+        # works in Pyodide
+        if hasattr(buffer, "to_py"):
+            return buffer.to_py()
+        # shims in MicroPython
+        return memoryview(as_bytearray(buffer))
+
+    async def blob(self):
+        return await self._response.blob()
+
+    async def bytearray(self):
+        buffer = await self._response.arrayBuffer()
+        return as_bytearray(buffer)
+
+    async def json(self):
+        return json.loads(await self.text())
+
+    async def text(self):
+        return await self._response.text()
+
+
+### allow direct await to _Response methods
+class _DirectResponse:
+    @staticmethod
+    def setup(promise, response):
+        promise._response = _Response(response)
+        return promise._response
+
+    def __init__(self, promise):
+        self._promise = promise
+        promise._response = None
+        promise.arrayBuffer = self.arrayBuffer
+        promise.blob = self.blob
+        promise.bytearray = self.bytearray
+        promise.json = self.json
+        promise.text = self.text
+
+    async def _response(self):
+        if not self._promise._response:
+            await self._promise
+        return self._promise._response
+
+    async def arrayBuffer(self):
+        response = await self._response()
+        return await response.arrayBuffer()
+
+    async def blob(self):
+        response = await self._response()
+        return await response.blob()
+
+    async def bytearray(self):
+        response = await self._response()
+        return await response.bytearray()
+
+    async def json(self):
+        response = await self._response()
+        return await response.json()
+
+    async def text(self):
+        response = await self._response()
+        return await response.text()
+
+
+def fetch(url, **kw):
+    # workaround Pyodide / MicroPython dict <-> js conversion
+    options = js.JSON.parse(json.dumps(kw))
+    awaited = lambda response, *args: _DirectResponse.setup(promise, response)
+    promise = js.fetch(url, options).then(awaited)
+    _DirectResponse(promise)
+    return promise

core/src/stdlib/pyscript/ffi.py

@@ -0,0 +1,18 @@
+try:
+    import js
+    from pyodide.ffi import create_proxy as _cp
+    from pyodide.ffi import to_js as _py_tjs
+
+    from_entries = js.Object.fromEntries
+
+    def _tjs(value, **kw):
+        if not hasattr(kw, "dict_converter"):
+            kw["dict_converter"] = from_entries
+        return _py_tjs(value, **kw)
+
+except:
+    from jsffi import create_proxy as _cp
+    from jsffi import to_js as _tjs
+
+create_proxy = _cp
+to_js = _tjs

core/src/stdlib/pyscript/flatted.py

@@ -0,0 +1,148 @@
+# https://www.npmjs.com/package/flatted
+
+import json as _json
+
+
+class _Known:
+    def __init__(self):
+        self.key = []
+        self.value = []
+
+
+class _String:
+    def __init__(self, value):
+        self.value = value
+
+
+def _array_keys(value):
+    keys = []
+    i = 0
+    for _ in value:
+        keys.append(i)
+        i += 1
+    return keys
+
+
+def _object_keys(value):
+    keys = []
+    for key in value:
+        keys.append(key)
+    return keys
+
+
+def _is_array(value):
+    return isinstance(value, (list, tuple))
+
+
+def _is_object(value):
+    return isinstance(value, dict)
+
+
+def _is_string(value):
+    return isinstance(value, str)
+
+
+def _index(known, input, value):
+    input.append(value)
+    index = str(len(input) - 1)
+    known.key.append(value)
+    known.value.append(index)
+    return index
+
+
+def _loop(keys, input, known, output):
+    for key in keys:
+        value = output[key]
+        if isinstance(value, _String):
+            _ref(key, input[int(value.value)], input, known, output)
+
+    return output
+
+
+def _ref(key, value, input, known, output):
+    if _is_array(value) and value not in known:
+        known.append(value)
+        value = _loop(_array_keys(value), input, known, value)
+    elif _is_object(value) and value not in known:
+        known.append(value)
+        value = _loop(_object_keys(value), input, known, value)
+
+    output[key] = value
+
+
+def _relate(known, input, value):
+    if _is_string(value) or _is_array(value) or _is_object(value):
+        try:
+            return known.value[known.key.index(value)]
+        except:
+            return _index(known, input, value)
+
+    return value
+
+
+def _transform(known, input, value):
+    if _is_array(value):
+        output = []
+        for val in value:
+            output.append(_relate(known, input, val))
+        return output
+
+    if _is_object(value):
+        obj = {}
+        for key in value:
+            obj[key] = _relate(known, input, value[key])
+        return obj
+
+    return value
+
+
+def _wrap(value):
+    if _is_string(value):
+        return _String(value)
+
+    if _is_array(value):
+        i = 0
+        for val in value:
+            value[i] = _wrap(val)
+            i += 1
+
+    elif _is_object(value):
+        for key in value:
+            value[key] = _wrap(value[key])
+
+    return value
+
+
+def parse(value, *args, **kwargs):
+    json = _json.loads(value, *args, **kwargs)
+    wrapped = []
+    for value in json:
+        wrapped.append(_wrap(value))
+
+    input = []
+    for value in wrapped:
+        if isinstance(value, _String):
+            input.append(value.value)
+        else:
+            input.append(value)
+
+    value = input[0]
+
+    if _is_array(value):
+        return _loop(_array_keys(value), input, [value], value)
+
+    if _is_object(value):
+        return _loop(_object_keys(value), input, [value], value)
+
+    return value
+
+
+def stringify(value, *args, **kwargs):
+    known = _Known()
+    input = []
+    output = []
+    i = int(_index(known, input, value))
+    while i < len(input):
+        output.append(_transform(known, input, input[i]))
+        i += 1
+    return _json.dumps(output, *args, **kwargs)

core/src/stdlib/pyscript/fs.py

@@ -0,0 +1,60 @@
+mounted = {}
+
+
+async def mount(path, mode="readwrite", root="", id="pyscript"):
+    import js
+    from _pyscript import fs, interpreter
+    from pyscript.ffi import to_js
+    from pyscript.magic_js import (
+        RUNNING_IN_WORKER,
+        sync,
+    )
+
+    js.console.warn("experimental pyscript.fs ⚠️")
+
+    handler = None
+
+    uid = f"{path}@{id}"
+
+    options = {"id": id, "mode": mode}
+    if root != "":
+        options["startIn"] = root
+
+    if RUNNING_IN_WORKER:
+        fsh = sync.storeFSHandler(uid, to_js(options))
+
+        # allow both async and/or SharedArrayBuffer use case
+        if isinstance(fsh, bool):
+            success = fsh
+        else:
+            success = await fsh
+
+        if success:
+            from polyscript import IDBMap
+
+            idb = IDBMap.new(fs.NAMESPACE)
+            handler = await idb.get(uid)
+        else:
+            raise RuntimeError(fs.ERROR)
+
+    else:
+        success = await fs.idb.has(uid)
+
+        if success:
+            handler = await fs.idb.get(uid)
+        else:
+            handler = await fs.getFileSystemDirectoryHandle(to_js(options))
+            await fs.idb.set(uid, handler)
+
+    mounted[path] = await interpreter.mountNativeFS(path, handler)
+
+
+async def sync(path):
+    await mounted[path].syncfs()
+
+
+async def unmount(path):
+    from _pyscript import interpreter
+
+    await sync(path)
+    interpreter._module.FS.unmount(path)

core/src/stdlib/pyscript/magic_js.py

@@ -0,0 +1,80 @@
+import json
+import sys
+
+import js as globalThis
+from polyscript import config as _config
+from polyscript import js_modules
+from pyscript.util import NotSupported
+
+RUNNING_IN_WORKER = not hasattr(globalThis, "document")
+
+config = json.loads(globalThis.JSON.stringify(_config))
+
+if "MicroPython" in sys.version:
+    config["type"] = "mpy"
+else:
+    config["type"] = "py"
+
+
+# allow `from pyscript.js_modules.xxx import yyy`
+class JSModule:
+    def __init__(self, name):
+        self.name = name
+
+    def __getattr__(self, field):
+        # avoid pyodide looking for non existent fields
+        if not field.startswith("_"):
+            return getattr(getattr(js_modules, self.name), field)
+        return None
+
+
+# generate N modules in the system that will proxy the real value
+for name in globalThis.Reflect.ownKeys(js_modules):
+    sys.modules[f"pyscript.js_modules.{name}"] = JSModule(name)
+sys.modules["pyscript.js_modules"] = js_modules
+
+if RUNNING_IN_WORKER:
+    import polyscript
+
+    PyWorker = NotSupported(
+        "pyscript.PyWorker",
+        "pyscript.PyWorker works only when running in the main thread",
+    )
+
+    try:
+        import js
+
+        window = polyscript.xworker.window
+        document = window.document
+        js.document = document
+        # this is the same as js_import on main and it lands modules on main
+        js_import = window.Function(
+            "return (...urls) => Promise.all(urls.map((url) => import(url)))"
+        )()
+    except:
+        message = "Unable to use `window` or `document` -> https://docs.pyscript.net/latest/faq/#sharedarraybuffer"
+        globalThis.console.warn(message)
+        window = NotSupported("pyscript.window", message)
+        document = NotSupported("pyscript.document", message)
+        js_import = None
+
+    sync = polyscript.xworker.sync
+
+    # in workers the display does not have a default ID
+    # but there is a sync utility from xworker
+    def current_target():
+        return polyscript.target
+
+else:
+    import _pyscript
+    from _pyscript import PyWorker, js_import
+
+    window = globalThis
+    document = globalThis.document
+    sync = NotSupported(
+        "pyscript.sync", "pyscript.sync works only when running in a worker"
+    )
+
+    # in MAIN the current element target exist, just use it
+    def current_target():
+        return _pyscript.target

core/src/stdlib/pyscript/media.py

@@ -0,0 +1,87 @@
+from pyscript import window
+from pyscript.ffi import to_js
+
+
+class Device:
+    """Device represents a media input or output device, such as a microphone,
+    camera, or headset.
+    """
+
+    def __init__(self, device):
+        self._dom_element = device
+
+    @property
+    def id(self):
+        return self._dom_element.deviceId
+
+    @property
+    def group(self):
+        return self._dom_element.groupId
+
+    @property
+    def kind(self):
+        return self._dom_element.kind
+
+    @property
+    def label(self):
+        return self._dom_element.label
+
+    def __getitem__(self, key):
+        return getattr(self, key)
+
+    @classmethod
+    async def load(cls, audio=False, video=True):
+        """
+        Load the device stream.
+        """
+        options = {}
+        options["audio"] = audio
+        if isinstance(video, bool):
+            options["video"] = video
+        else:
+            options["video"] = {}
+            for k in video:
+                options["video"][k] = video[k]
+        return await window.navigator.mediaDevices.getUserMedia(to_js(options))
+
+    async def get_stream(self):
+        key = self.kind.replace("input", "").replace("output", "")
+        options = {key: {"deviceId": {"exact": self.id}}}
+        return await self.load(**options)
+
+
+async def list_devices() -> list[dict]:
+    """
+    Return the list of the currently available media input and output devices,
+    such as microphones, cameras, headsets, and so forth.
+
+    Output:
+
+        list(dict) - list of dictionaries representing the available media devices.
+            Each dictionary has the following keys:
+            * deviceId: a string that is an identifier for the represented device
+                that is persisted across sessions. It is un-guessable by other
+                applications and unique to the origin of the calling application.
+                It is reset when the user clears cookies (for Private Browsing, a
+                different identifier is used that is not persisted across sessions).
+
+            * groupId: a string that is a group identifier. Two devices have the same
+                group identifier if they belong to the same physical device — for
+                example a monitor with both a built-in camera and a microphone.
+
+            * kind: an enumerated value that is either "videoinput", "audioinput"
+                or "audiooutput".
+
+            * label: a string describing this device (for example "External USB
+                Webcam").
+
+    Note: the returned list will omit any devices that are blocked by the document
+    Permission Policy: microphone, camera, speaker-selection (for output devices),
+    and so on. Access to particular non-default devices is also gated by the
+    Permissions API, and the list will omit devices for which the user has not
+    granted explicit permission.
+    """
+    # https://developer.mozilla.org/en-US/docs/Web/API/MediaDevices/enumerateDevices
+    return [
+        Device(obj) for obj in await window.navigator.mediaDevices.enumerateDevices()
+    ]

core/src/stdlib/pyscript/storage.py

@@ -0,0 +1,62 @@
+from polyscript import storage as _storage
+from pyscript.flatted import parse as _parse
+from pyscript.flatted import stringify as _stringify
+
+
+# convert a Python value into an IndexedDB compatible entry
+def _to_idb(value):
+    if value is None:
+        return _stringify(["null", 0])
+    if isinstance(value, (bool, float, int, str, list, dict, tuple)):
+        return _stringify(["generic", value])
+    if isinstance(value, bytearray):
+        return _stringify(["bytearray", list(value)])
+    if isinstance(value, memoryview):
+        return _stringify(["memoryview", list(value)])
+    msg = f"Unexpected value: {value}"
+    raise TypeError(msg)
+
+
+# convert an IndexedDB compatible entry into a Python value
+def _from_idb(value):
+    (
+        kind,
+        result,
+    ) = _parse(value)
+    if kind == "null":
+        return None
+    if kind == "generic":
+        return result
+    if kind == "bytearray":
+        return bytearray(result)
+    if kind == "memoryview":
+        return memoryview(bytearray(result))
+    return value
+
+
+class Storage(dict):
+    def __init__(self, store):
+        super().__init__({k: _from_idb(v) for k, v in store.entries()})
+        self.__store__ = store
+
+    def __delitem__(self, attr):
+        self.__store__.delete(attr)
+        super().__delitem__(attr)
+
+    def __setitem__(self, attr, value):
+        self.__store__.set(attr, _to_idb(value))
+        super().__setitem__(attr, value)
+
+    def clear(self):
+        self.__store__.clear()
+        super().clear()
+
+    async def sync(self):
+        await self.__store__.sync()
+
+
+async def storage(name="", storage_class=Storage):
+    if not name:
+        msg = "The storage name must be defined"
+        raise ValueError(msg)
+    return storage_class(await _storage(f"@pyscript/{name}"))

core/src/stdlib/pyscript/util.py

@@ -0,0 +1,58 @@
+import js
+import sys
+import inspect
+
+
+def as_bytearray(buffer):
+    """
+    Given a JavaScript ArrayBuffer, convert it to a Python bytearray in a
+    MicroPython friendly manner.
+    """
+    ui8a = js.Uint8Array.new(buffer)
+    size = ui8a.length
+    ba = bytearray(size)
+    for i in range(size):
+        ba[i] = ui8a[i]
+    return ba
+
+
+class NotSupported:
+    """
+    Small helper that raises exceptions if you try to get/set any attribute on
+    it.
+    """
+
+    def __init__(self, name, error):
+        object.__setattr__(self, "name", name)
+        object.__setattr__(self, "error", error)
+
+    def __repr__(self):
+        return f"<NotSupported {self.name} [{self.error}]>"
+
+    def __getattr__(self, attr):
+        raise AttributeError(self.error)
+
+    def __setattr__(self, attr, value):
+        raise AttributeError(self.error)
+
+    def __call__(self, *args):
+        raise TypeError(self.error)
+
+
+def is_awaitable(obj):
+    """
+    Returns a boolean indication if the passed in obj is an awaitable
+    function. (MicroPython treats awaitables as generator functions, and if
+    the object is a closure containing an async function we need to work
+    carefully.)
+    """
+    from pyscript import config
+
+    if config["type"] == "mpy":  # Is MicroPython?
+        # MicroPython doesn't appear to have a way to determine if a closure is
+        # an async function except via the repr. This is a bit hacky.
+        if "<closure <generator>" in repr(obj):
+            return True
+        return inspect.isgeneratorfunction(obj)
+
+    return inspect.iscoroutinefunction(obj)

core/src/stdlib/pyscript/websocket.py

@@ -0,0 +1,71 @@
+import js
+from pyscript.ffi import create_proxy
+from pyscript.util import as_bytearray
+
+code = "code"
+protocols = "protocols"
+reason = "reason"
+methods = ["onclose", "onerror", "onmessage", "onopen"]
+
+
+class EventMessage:
+    def __init__(self, event):
+        self._event = event
+
+    def __getattr__(self, attr):
+        value = getattr(self._event, attr)
+
+        if attr == "data" and not isinstance(value, str):
+            if hasattr(value, "to_py"):
+                return value.to_py()
+            # shims in MicroPython
+            return memoryview(as_bytearray(value))
+
+        return value
+
+
+class WebSocket:
+    CONNECTING = 0
+    OPEN = 1
+    CLOSING = 2
+    CLOSED = 3
+
+    def __init__(self, **kw):
+        url = kw["url"]
+        if protocols in kw:
+            socket = js.WebSocket.new(url, kw[protocols])
+        else:
+            socket = js.WebSocket.new(url)
+        object.__setattr__(self, "_ws", socket)
+
+        for t in methods:
+            if t in kw:
+                # Pyodide fails at setting socket[t] directly
+                setattr(socket, t, create_proxy(kw[t]))
+
+    def __getattr__(self, attr):
+        return getattr(self._ws, attr)
+
+    def __setattr__(self, attr, value):
+        if attr in methods:
+            m = lambda e: value(EventMessage(e))
+            setattr(self._ws, attr, create_proxy(m))
+        else:
+            setattr(self._ws, attr, value)
+
+    def close(self, **kw):
+        if code in kw and reason in kw:
+            self._ws.close(kw[code], kw[reason])
+        elif code in kw:
+            self._ws.close(kw[code])
+        else:
+            self._ws.close()
+
+    def send(self, data):
+        if isinstance(data, str):
+            self._ws.send(data)
+        else:
+            buffer = js.Uint8Array.new(len(data))
+            for pos, b in enumerate(data):
+                buffer[pos] = b
+            self._ws.send(buffer)

core/src/stdlib/pyscript/workers.py

@@ -0,0 +1,45 @@
+import js as _js
+from polyscript import workers as _workers
+
+_get = _js.Reflect.get
+
+
+def _set(script, name, value=""):
+    script.setAttribute(name, value)
+
+
+# this solves an inconsistency between Pyodide and MicroPython
+# @see https://github.com/pyscript/pyscript/issues/2106
+class _ReadOnlyProxy:
+    def __getitem__(self, name):
+        return _get(_workers, name)
+
+    def __getattr__(self, name):
+        return _get(_workers, name)
+
+
+workers = _ReadOnlyProxy()
+
+
+async def create_named_worker(src="", name="", config=None, type="py"):
+    from json import dumps
+
+    if not src:
+        msg = "Named workers require src"
+        raise ValueError(msg)
+
+    if not name:
+        msg = "Named workers require a name"
+        raise ValueError(msg)
+
+    s = _js.document.createElement("script")
+    s.type = type
+    s.src = src
+    _set(s, "worker")
+    _set(s, "name", name)
+
+    if config:
+        _set(s, "config", (isinstance(config, str) and config) or dumps(config))
+
+    _js.document.body.append(s)
+    return await workers[name]

core/src/storage.js

@@ -0,0 +1,72 @@
+import { ArrayBuffer, TypedArray } from "sabayon/shared";
+import IDBMapSync from "@webreflection/idb-map/sync";
+import { parse, stringify } from "flatted";
+
+const to_idb = (value) => {
+    if (value == null) return stringify(["null", 0]);
+    /* eslint-disable no-fallthrough */
+    switch (typeof value) {
+        case "object": {
+            if (value instanceof TypedArray)
+                return stringify(["memoryview", [...value]]);
+            if (value instanceof ArrayBuffer)
+                return stringify(["bytearray", [...new Uint8Array(value)]]);
+        }
+        case "string":
+        case "number":
+        case "boolean":
+            return stringify(["generic", value]);
+        default:
+            throw new TypeError(`Unexpected value: ${String(value)}`);
+    }
+};
+
+const from_idb = (value) => {
+    const [kind, result] = parse(value);
+    if (kind === "null") return null;
+    if (kind === "generic") return result;
+    if (kind === "bytearray") return new Uint8Array(value).buffer;
+    if (kind === "memoryview") return new Uint8Array(value);
+    return value;
+};
+
+// this export simulate pyscript.storage exposed in the Python world
+export const storage = async (name) => {
+    if (!name) throw new SyntaxError("The storage name must be defined");
+
+    const store = new IDBMapSync(`@pyscript/${name}`);
+    const map = new Map();
+    await store.sync();
+    for (const [k, v] of store.entries()) map.set(k, from_idb(v));
+
+    const clear = () => {
+        map.clear();
+        store.clear();
+    };
+
+    const sync = async () => {
+        await store.sync();
+    };
+
+    return new Proxy(map, {
+        ownKeys: (map) => [...map.keys()],
+        has: (map, name) => map.has(name),
+        get: (map, name) => {
+            if (name === "clear") return clear;
+            if (name === "sync") return sync;
+            return map.get(name);
+        },
+        set: (map, name, value) => {
+            map.set(name, value);
+            store.set(name, to_idb(value));
+            return true;
+        },
+        deleteProperty: (map, name) => {
+            if (map.has(name)) {
+                map.delete(name);
+                store.delete(name);
+            }
+            return true;
+        },
+    });
+};

core/src/sync.js

@@ -0,0 +1,31 @@
+import { idb, getFileSystemDirectoryHandle } from "./fs.js";
+
+export default {
+    // allow pyterminal checks to bootstrap
+    is_pyterminal: () => false,
+
+    /**
+     * 'Sleep' for the given number of seconds. Used to implement Python's time.sleep in Worker threads.
+     * @param {number} seconds The number of seconds to sleep.
+     */
+    sleep(seconds) {
+        return new Promise(($) => setTimeout($, seconds * 1000));
+    },
+
+    /**
+     * Ask a user action via dialog and returns the directory handler once granted.
+     * @param {string} uid
+     * @param {{id?:string, mode?:"read"|"readwrite", hint?:"desktop"|"documents"|"downloads"|"music"|"pictures"|"videos"}} options
+     * @returns {boolean}
+     */
+    async storeFSHandler(uid, options = {}) {
+        if (await idb.has(uid)) return true;
+        return getFileSystemDirectoryHandle(options).then(
+            async (handler) => {
+                await idb.set(uid, handler);
+                return true;
+            },
+            () => false,
+        );
+    },
+};

core/tests/README.md

@@ -0,0 +1,49 @@
+# PyScript Test Suite
+
+There are three aspects to our test suite. These are reflected in the layout of
+the test directory:
+
+1. `python` - contains the Python based test suite to exercise Python code
+   **within** PyScript. These tests are run four differeng ways to ensure all
+   combination of MicroPython/Pyodide and main thread/worker contexts are
+   checked.
+2. `javascript` - contains JavaScript tests to exercise PyScript _itself_, in
+   the browser.
+3. `manual` - contains tests to run manually in a browser, due to the complex
+   nature of the tests.
+
+We use [Playwright](https://playwright.dev/) to automate the running of the
+Python and JavaScript test suites. We use
+[uPyTest](https://github.com/ntoll/upytest) as a test framework for the Python
+test suite. uPyTest is a "PyTest inspired" framework for running tests in the
+browser on both MicroPython and Pyodide.
+
+The automated (Playwright) tests are specified in the `integration.spec.js`
+file in this directory.
+
+All automatic tests live in either the `python` or `javascript` folders. All
+the tests in these folder are run by CI or locally run by `make test` in the
+root of this project. Alternatively, run `npm run test:integration` in the
+PyScript source directory.
+
+Similarly, some tests can only be run manually (due to their nature or
+underlying complexity). These are in the `manual` directory and are in the form
+of separate directories (each containing an `index.html`) or individual `*.html`
+files to which you point your browser. Each separate test may exercise
+JavaScript or Python code (or both), and the context for each separate test is
+kept carefully isolated.
+
+Some rules of thumb:
+
+* We don't test upstream projects: we assume they have their own test suites,
+  and if we find bugs, we file an issue upstream with an example of how to
+  recreate the problem.
+* We don't test browser functionality, we just have to trust that browsers work
+  as advertised. Once again, if we find an issue, we report upstream.
+* All test cases should include commentary describing the **intent** and
+  context of the test.
+* Tests in Python use [uPyTest](https://github.com/ntoll/upytest) (see the
+  README for documentation), an "inspired by PyTest" test framework that works
+  with both MicroPython and Pyodide in the browser. This means that all
+  Python tests should work with both interpreters.
+* Tests in JavaScript... (Andrea to explain). ;-)

core/tests/javascript/async-listener.html

@@ -0,0 +1,24 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <link rel="stylesheet" href="../../dist/core.css">
+    <script type="module" src="../../dist/core.js"></script>
+</head>
+<body>
+  <script type="mpy">
+    from pyscript import window, document, fetch, when
+
+    @when('click', '#click')
+    async def click(event):
+      text = await fetch(window.location.href).text()
+      document.getElementById('output').append(text)
+      document.documentElement.classList.add('ok')
+
+    document.getElementById('click').click()
+  </script>
+  <button id="click">click</button>
+  <pre id="output"></pre>
+</body>
+</html>

core/tests/javascript/config-url.html

@@ -0,0 +1,25 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1.0">
+  <title>PyScript Next Plugin</title>
+  <link rel="stylesheet" href="../../dist/core.css">
+  <script type="module" src="../../dist/core.js"></script>
+  <mpy-config src="config-url/config.json"></mpy-config>
+  <script type="mpy">
+    from pyscript import config
+    if config["files"]["{TO}"] != "./runtime":
+        raise Exception("wrong config tree")
+
+    from runtime import test
+  </script>
+  <script type="mpy" worker>
+    from pyscript import config
+    if config["files"]["{TO}"] != "./runtime":
+        raise Exception("wrong config tree")
+
+    from runtime import test
+  </script>
+</head>
+</html>

core/tests/javascript/config-url/config.json

@@ -0,0 +1,7 @@
+{
+    "files":{
+        "{FROM}": "./src",
+        "{TO}": "./runtime",
+        "{FROM}/test.py": "{TO}/test.py"
+    }
+}

core/tests/javascript/config-url/src/test.py

@@ -0,0 +1,8 @@
+from pyscript import RUNNING_IN_WORKER, document
+
+classList = document.documentElement.classList
+
+if RUNNING_IN_WORKER:
+    classList.add("worker")
+else:
+    classList.add("main")

core/tests/javascript/config_type.html

@@ -0,0 +1,23 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <link rel="stylesheet" href="../../dist/core.css">
+    <script type="module" src="../../dist/core.js"></script>
+</head>
+<body>
+    <script type="mpy">
+      from pyscript import config, document
+
+      if config["type"] is "mpy":
+        document.documentElement.classList.add("mpy")
+    </script>
+    <script type="py">
+      from pyscript import config, document
+
+      if config["type"] is "py":
+        document.documentElement.classList.add("py")
+    </script>
+</body>
+</html>

core/tests/javascript/fetch/index.html

@@ -0,0 +1,95 @@
+<!doctype html>
+<html lang="en">
+    <head>
+        <meta charset="UTF-8" />
+        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+        <link rel="stylesheet" href="../../../dist/core.css">
+    </head>
+    <body>
+      <script type="module">
+        import fetch from 'https://esm.run/@webreflection/fetch';
+
+        globalThis.fetch_text = await fetch("config.json").text();
+        globalThis.fetch_json = JSON.stringify(await fetch("config.json").json());
+        globalThis.fetch_buffer = new Uint8Array((await fetch("config.json").arrayBuffer())).length;
+
+        document.head.appendChild(
+          Object.assign(
+            document.createElement('script'),
+            {
+              type: 'module',
+              src: '../../../dist/core.js'
+            }
+          )
+        );
+      </script>
+      <script type="mpy" async>
+        import js, json
+        from pyscript import document, fetch
+
+        fetch_text = await (await fetch("config.json")).text()
+        if (fetch_text != js.fetch_text):
+          raise Exception("fetch_text")
+
+        fetch_text = await fetch("config.json").text()
+        if (fetch_text != js.fetch_text):
+          raise Exception("fetch_text")
+
+        fetch_json = await (await fetch("config.json")).json()
+        if (json.dumps(fetch_json).replace(" ", "") != js.fetch_json):
+          raise Exception("fetch_json")
+
+        fetch_json = await fetch("config.json").json()
+        if (json.dumps(fetch_json).replace(" ", "") != js.fetch_json):
+          raise Exception("fetch_json")
+
+        fetch_buffer = await (await fetch("config.json")).arrayBuffer()
+        if (len(fetch_buffer) != js.fetch_buffer):
+          raise Exception("fetch_buffer")
+
+        fetch_buffer = await fetch("config.json").arrayBuffer()
+        if (len(fetch_buffer) != js.fetch_buffer):
+          raise Exception("fetch_buffer")
+
+        print(await (await fetch("config.json")).bytearray())
+        print(await (await fetch("config.json")).blob())
+
+        if (await fetch("shenanigans.nope")).ok == False:
+          document.documentElement.classList.add('mpy')
+      </script>
+      <script type="py" async>
+        import js, json
+        from pyscript import document, fetch
+
+        fetch_text = await (await fetch("config.json")).text()
+        if (fetch_text != js.fetch_text):
+          raise Exception("fetch_text")
+
+        fetch_text = await fetch("config.json").text()
+        if (fetch_text != js.fetch_text):
+          raise Exception("fetch_text")
+
+        fetch_json = await (await fetch("config.json")).json()
+        if (json.dumps(fetch_json).replace(" ", "") != js.fetch_json):
+          raise Exception("fetch_json")
+
+        fetch_json = await fetch("config.json").json()
+        if (json.dumps(fetch_json).replace(" ", "") != js.fetch_json):
+          raise Exception("fetch_json")
+
+        fetch_buffer = await (await fetch("config.json")).arrayBuffer()
+        if (len(fetch_buffer) != js.fetch_buffer):
+          raise Exception("fetch_buffer")
+
+        fetch_buffer = await fetch("config.json").arrayBuffer()
+        if (len(fetch_buffer) != js.fetch_buffer):
+          raise Exception("fetch_buffer")
+
+        print(await (await fetch("config.json")).bytearray())
+        print(await (await fetch("config.json")).blob())
+
+        if (await fetch("shenanigans.nope")).ok == False:
+          document.documentElement.classList.add('py')
+      </script>
+    </body>
+</html>

core/tests/javascript/ffi.html

@@ -0,0 +1,26 @@
+<!doctype html>
+<html lang="en">
+    <head>
+        <meta charset="UTF-8" />
+        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+        <title>PyScript FFI</title>
+        <link rel="stylesheet" href="../../dist/core.css">
+        <script type="module" src="../../dist/core.js"></script>
+    </head>
+    <body>
+      <script type="mpy">
+          from pyscript import document
+          from pyscript.ffi import to_js
+          document.documentElement.classList.add(
+            to_js({"ok": "mpy"}).ok
+          )
+      </script>
+      <script type="py">
+          from pyscript import document
+          from pyscript.ffi import to_js
+          document.documentElement.classList.add(
+            to_js({"ok": "py"}).ok
+          )
+      </script>
+    </body>
+</html>

core/tests/javascript/hooks.html

@@ -0,0 +1,60 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1.0">
+  <title>PyScript Next Plugin Bug?</title>
+  <link rel="stylesheet" href="../../dist/core.css">
+  <script type="module">
+    addEventListener('mpy:done', () => {
+      document.documentElement.classList.add('done');
+    });
+
+    import { hooks } from "../../dist/core.js";
+
+    // Main
+    hooks.main.onReady.add((wrap, element) => {
+      console.log("main", "onReady");
+      if (location.search === '?debug') {
+        console.debug("main", "wrap", wrap);
+        console.debug("main", "element", element);
+      }
+    });
+    hooks.main.onBeforeRun.add(() => {
+      console.log("main", "onBeforeRun");
+    });
+    hooks.main.codeBeforeRun.add('print("main", "codeBeforeRun")');
+    hooks.main.codeAfterRun.add('print("main", "codeAfterRun")');
+    hooks.main.onAfterRun.add(() => {
+      console.log("main", "onAfterRun");
+    });
+
+    // Worker
+    hooks.worker.onReady.add((wrap, xworker) => {
+      console.log("worker", "onReady");
+      if (location.search === '?debug') {
+        console.debug("worker", "wrap", wrap);
+        console.debug("worker", "xworker", xworker);
+      }
+    });
+    hooks.worker.onBeforeRun.add(() => {
+      console.log("worker", "onBeforeRun");
+    });
+    hooks.worker.codeBeforeRun.add('print("worker", "codeBeforeRun")');
+    hooks.worker.codeAfterRun.add('print("worker", "codeAfterRun")');
+    hooks.worker.onAfterRun.add(() => {
+      console.log("worker", "onAfterRun");
+    });
+  </script>
+</head>
+<body>
+  <script type="mpy" async="false" worker>
+    from pyscript import document
+    print("actual code in worker")
+    document.documentElement.classList.add('worker')
+  </script>
+  <script type="mpy" async="false">
+    print("actual code in main")
+  </script>
+</body>
+</html>

core/tests/javascript/issue-2093/error.js

@@ -0,0 +1,6 @@
+const { error } = console;
+
+console.error = (...args) => {
+  error(...args);
+  document.documentElement.classList.add('errored');
+};

core/tests/javascript/issue-2093/index.html

@@ -0,0 +1,16 @@
+<!doctype html>
+<html lang="en">
+    <head>
+        <meta charset="UTF-8">
+        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+        <link rel="stylesheet" href="../../../dist/core.css">
+        <script type="module" src="./error.js"></script>
+        <script type="module" src="../../../dist/core.js"></script>
+    </head>
+    <body>
+      <script type="mpy-editor" setup>
+        print("Hello Editor")
+        raise Exception("failure")
+      </script>
+    </body>
+</html>

core/tests/javascript/js-storage.html

@@ -0,0 +1,28 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <link rel="stylesheet" href="../../dist/core.css">
+    <script type="module">
+      import { storage } from '../../dist/storage.js';
+
+      const store = await storage('js-storage');
+      store.test = [1, 2, 3].map(String);
+      await store.sync();
+
+      // be sure the store is not empty before bootstrap
+      import('../../dist/core.js');
+    </script>
+</head>
+<body>
+  <script type="mpy">
+    from pyscript import storage, document
+
+    store = await storage("js-storage")
+
+    if ",".join(store["test"]) == "1,2,3":
+        document.documentElement.classList.add("ok")
+  </script>
+</body>
+</html>

core/tests/javascript/js_modules.html

@@ -0,0 +1,39 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <link rel="stylesheet" href="../../dist/core.css">
+    <script type="module" src="../../dist/core.js"></script>
+</head>
+<body>
+    <mpy-config>
+        [js_modules.main]
+        "./js_modules.js" = "random_js"
+    </mpy-config>
+    <mpy-script>
+        from pyscript.js_modules.random_js import default as value
+        from pyscript.js_modules import random_js
+        from pyscript import js_modules
+
+        print("mpy", value)
+        print("mpy", random_js.default)
+        print("mpy", js_modules.random_js.default)
+    </mpy-script>
+    <py-config>
+        [js_modules.main]
+        "./js_modules.js" = "random_js"
+    </py-config>
+    <py-script>
+        from pyscript.js_modules.random_js import default as value
+        from pyscript.js_modules import random_js
+        from pyscript import js_modules, document
+
+        print("py", value)
+        print("py", random_js.default)
+        print("py", js_modules.random_js.default)
+
+        document.documentElement.classList.add('done')
+    </py-script>
+</body>
+</html>

core/tests/javascript/js_modules.js

@@ -0,0 +1 @@
+export default Math.random();

core/tests/javascript/loader/index.html

@@ -0,0 +1,29 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1.0">
+  <link rel="stylesheet" href="../../../dist/core.css">
+  <script type="module">
+    import '../../../dist/core.js';
+
+    addEventListener('py:progress', ({ detail }) => {
+      document.body.append(
+        detail,
+        document.createElement('br'),
+      );
+    });
+  </script>
+</head>
+<body>
+  <py-config>
+    packages = ["matplotlib"]
+  </py-config>
+  <script type="py" worker>
+    from pyscript import document
+    from sys import version
+    document.body.append(document.createElement('hr'), version)
+    document.documentElement.classList.add('ok')
+  </script>
+</body>
+</html>