Fix antigravity (#1017)

* Fix antigravity

* Add test

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

examples/antigravity.py

@@ -1,5 +1,4 @@
 import random
-import sys
 
 from js import DOMParser, document, setInterval
 from pyodide.ffi import create_proxy
@@ -11,9 +10,10 @@ class Antigravity:
     url = "./antigravity.svg"
 
     def __init__(self, target=None, interval=10, append=True, fly=False):
-        target = target or sys.stdout._out
         self.target = (
-            document.getElementById(target) if isinstance(target, str) else target
+            document.getElementById(target)
+            if isinstance(target, str)
+            else document.body
         )
         doc = DOMParser.new().parseFromString(
             open_url(self.url).read(), "image/svg+xml"

pyscriptjs/tests/integration/test_zz_examples.py

@@ -98,6 +98,29 @@ class TestExamples(PyScriptTest):
         assert see_source_link.is_visible()
         self.assert_no_banners()
 
+    def test_antigravity(self):
+        self.goto("examples/antigravity.html")
+        self.wait_for_pyscript()
+        assert self.page.title() == "Antigravity"
+
+        # confirm that svg added to page
+        wait_for_render(self.page, "*", '<svg.*id="svg8".*>')
+
+        # Get svg layer of flying character
+        char = self.page.wait_for_selector("#python")
+        assert char is not None
+
+        # check that character moves in negative-y direction over time
+        ycoord_pattern = r"translate\(-?\d*\.\d*,\s(?P<ycoord>-?[\d.]+)\)"
+        starting_y_coord = float(
+            re.match(ycoord_pattern, char.get_attribute("transform")).group("ycoord")
+        )
+        time.sleep(2)
+        later_y_coord = float(
+            re.match(ycoord_pattern, char.get_attribute("transform")).group("ycoord")
+        )
+        assert later_y_coord < starting_y_coord
+
     def test_bokeh(self):
         # XXX improve this test
         self.goto("examples/bokeh.html")