Fix getQueryInfo() 'from ' detection closes #4810 (rebased) (#4884)

* Add test for #4810: getQueryInfo() fails to detect 'from ' correctly

This test demonstrates that getQueryInfo("from ") incorrectly returns
EditingTable = false when it should return true. This prevents autocomplete
from suggesting tables after users type "from ".

The test currently fails as expected, proving the bug exists.

Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* Fix #4810: Correct getQueryInfo() 'from ' detection for autocomplete

This commit fixes a bug where getQueryInfo("from ") incorrectly returned
EditingTable = false, preventing autocomplete from suggesting tables after
users type "from ".

The fix involves two changes:

1. Modified getPreviousWord() to correctly return "from" when the input is
   "from " (single word followed by space). Previously, it returned an empty
   string because it couldn't find a space before "from".

2. Modified isEditingTable() to check that the text ends with a space. This
   ensures we only enable table suggestions when the user has typed "from "
   (ready for a table name), not when they're in the middle of typing "from"
   or after they've already started typing a table name like "from my_table".

The combination of these changes ensures:
- "from " → EditingTable = true (autocomplete shows tables)
- "from my_table" → EditingTable = false (autocomplete doesn't interfere)
- "from" → EditingTable = false (no space yet, not ready for table name)

All existing tests pass, and the new test from the previous commit now passes.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

---------

Co-authored-by: Claude <noreply@anthropic.com>

pkg/interactive/interactive_client_test.go

@@ -580,3 +580,53 @@ func TestInitialisationComplete_RaceCondition(t *testing.T) {
 
 	wg.Wait()
 }
+
+// TestGetQueryInfo_FromDetection tests that getQueryInfo correctly detects
+// when the user is editing a table name after typing "from ".
+//
+// This is important for autocomplete - when a user types "from " (with a space),
+// the system should recognize they are about to enter a table name and enable
+// table suggestions.
+//
+// Bug: #4810
+func TestGetQueryInfo_FromDetection(t *testing.T) {
+	tests := []struct {
+		name              string
+		input             string
+		expectedTable     string
+		expectedEditTable bool
+	}{
+		{
+			name:              "just_from",
+			input:             "from ",
+			expectedTable:     "",
+			expectedEditTable: true, // Should be true - user is about to enter table name
+		},
+		{
+			name:              "from_with_table",
+			input:             "from my_table",
+			expectedTable:     "my_table",
+			expectedEditTable: false, // Not editing, already entered
+		},
+		{
+			name:              "from_keyword_only",
+			input:             "from",
+			expectedTable:     "",
+			expectedEditTable: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := getQueryInfo(tt.input)
+
+			if result.Table != tt.expectedTable {
+				t.Errorf("getQueryInfo(%q).Table = %q, expected %q", tt.input, result.Table, tt.expectedTable)
+			}
+
+			if result.EditingTable != tt.expectedEditTable {
+				t.Errorf("getQueryInfo(%q).EditingTable = %v, expected %v", tt.input, result.EditingTable, tt.expectedEditTable)
+			}
+		})
+	}
+}

pkg/interactive/interactive_helpers.go

@@ -17,12 +17,16 @@ func getQueryInfo(text string) *queryCompletionInfo {
 
 	return &queryCompletionInfo{
 		Table:        table,
-		EditingTable: isEditingTable(prevWord),
+		EditingTable: isEditingTable(text, prevWord),
 	}
 }
 
-func isEditingTable(prevWord string) bool {
-	var editingTable = prevWord == "from"
+func isEditingTable(text string, prevWord string) bool {
+	// Only consider it editing table if:
+	// 1. The previous word is "from"
+	// 2. The text ends with a space (meaning cursor is after "from ", not in the middle of typing a table name)
+	endsWithSpace := len(text) > 0 && text[len(text)-1] == ' '
+	var editingTable = prevWord == "from" && endsWithSpace
 	return editingTable
 }
 
@@ -52,7 +56,8 @@ func getPreviousWord(text string) string {
 	}
 	prevSpace := strings.LastIndex(text[:lastNotSpace], " ")
 	if prevSpace == -1 {
-		return ""
+		// No space before the word, so return from the beginning to lastNotSpace
+		return text[0 : lastNotSpace+1]
 	}
 	return text[prevSpace+1 : lastNotSpace+1]
 }

pkg/interactive/interactive_helpers_test.go

@@ -200,9 +200,9 @@ func TestGetPreviousWord(t *testing.T) {
 			expected: "from",
 		},
 		{
-			name:     "no previous word",
+			name:     "single word with trailing space",
 			input:    "select ",
-			expected: "",
+			expected: "select",
 		},
 		{
 			name:     "single word",
@@ -324,31 +324,43 @@ func TestGetTable(t *testing.T) {
 func TestIsEditingTable(t *testing.T) {
 	tests := []struct {
 		name     string
+		text     string
 		prevWord string
 		expected bool
 	}{
 		{
-			name:     "from keyword",
+			name:     "from keyword with trailing space",
+			text:     "from ",
 			prevWord: "from",
 			expected: true,
 		},
+		{
+			name:     "from keyword without trailing space",
+			text:     "from",
+			prevWord: "from",
+			expected: false,
+		},
 		{
 			name:     "not from keyword",
+			text:     "select ",
 			prevWord: "select",
 			expected: false,
 		},
 		{
 			name:     "empty string",
+			text:     "",
 			prevWord: "",
 			expected: false,
 		},
 		{
 			name:     "FROM uppercase",
+			text:     "FROM ",
 			prevWord: "FROM",
 			expected: false,
 		},
 		{
 			name:     "whitespace",
+			text:     " from ",
 			prevWord: " from ",
 			expected: false,
 		},
@@ -356,9 +368,9 @@ func TestIsEditingTable(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			result := isEditingTable(tt.prevWord)
+			result := isEditingTable(tt.text, tt.prevWord)
 			if result != tt.expected {
-				t.Errorf("isEditingTable(%q) = %v, want %v", tt.prevWord, result, tt.expected)
+				t.Errorf("isEditingTable(%q, %q) = %v, want %v", tt.text, tt.prevWord, result, tt.expected)
 			}
 		})
 	}