Fixes #34779: Do not trim long text in the current page if a screen reader is known to be attached

src/vs/editor/browser/controller/textAreaHandler.ts

@@ -182,7 +182,7 @@ export class TextAreaHandler extends ViewPart {
 					return TextAreaState.EMPTY;
 				}
 
-				return PagedScreenReaderStrategy.fromEditorSelection(currentState, simpleModel, this._selections[0]);
+				return PagedScreenReaderStrategy.fromEditorSelection(currentState, simpleModel, this._selections[0], this._accessibilitySupport === platform.AccessibilitySupport.Unknown);
 			},
 
 			deduceModelPosition: (viewAnchorPosition: Position, deltaOffset: number, lineFeedCnt: number): Position => {

src/vs/editor/browser/controller/textAreaState.ts

@@ -241,7 +241,7 @@ export class PagedScreenReaderStrategy {
 		return new Range(startLineNumber, 1, endLineNumber + 1, 1);
 	}
 
-	public static fromEditorSelection(previousState: TextAreaState, model: ISimpleModel, selection: Range): TextAreaState {
+	public static fromEditorSelection(previousState: TextAreaState, model: ISimpleModel, selection: Range, trimLongText: boolean): TextAreaState {
 
 		let selectionStartPage = PagedScreenReaderStrategy._getPageOfLine(selection.startLineNumber);
 		let selectionStartPageRange = PagedScreenReaderStrategy._getRangeForPage(selectionStartPage);
@@ -273,15 +273,17 @@ export class PagedScreenReaderStrategy {
 
 		// Chromium handles very poorly text even of a few thousand chars
 		// Cut text to avoid stalling the entire UI
-		const LIMIT_CHARS = 500;
-		if (pretext.length > LIMIT_CHARS) {
-			pretext = pretext.substring(pretext.length - LIMIT_CHARS, pretext.length);
-		}
-		if (posttext.length > LIMIT_CHARS) {
-			posttext = posttext.substring(0, LIMIT_CHARS);
-		}
-		if (text.length > 2 * LIMIT_CHARS) {
-			text = text.substring(0, LIMIT_CHARS) + String.fromCharCode(8230) + text.substring(text.length - LIMIT_CHARS, text.length);
+		if (trimLongText) {
+			const LIMIT_CHARS = 500;
+			if (pretext.length > LIMIT_CHARS) {
+				pretext = pretext.substring(pretext.length - LIMIT_CHARS, pretext.length);
+			}
+			if (posttext.length > LIMIT_CHARS) {
+				posttext = posttext.substring(0, LIMIT_CHARS);
+			}
+			if (text.length > 2 * LIMIT_CHARS) {
+				text = text.substring(0, LIMIT_CHARS) + String.fromCharCode(8230) + text.substring(text.length - LIMIT_CHARS, text.length);
+			}
 		}
 
 		return new TextAreaState(pretext + text + posttext, pretext.length, pretext.length + text.length, new Position(selection.startLineNumber, selection.startColumn), new Position(selection.endLineNumber, selection.endColumn));

src/vs/editor/test/browser/controller/imeTester.ts

@@ -100,7 +100,7 @@ function doCreateTest(description: string, inputStr: string, expectedStr: string
 
 			const selection = new Range(1, 1 + cursorOffset, 1, 1 + cursorOffset + cursorLength);
 
-			return PagedScreenReaderStrategy.fromEditorSelection(currentState, model, selection);
+			return PagedScreenReaderStrategy.fromEditorSelection(currentState, model, selection, true);
 		},
 		deduceModelPosition: (viewAnchorPosition: Position, deltaOffset: number, lineFeedCnt: number): Position => {
 			return null;

src/vs/editor/test/browser/controller/textAreaState.test.ts

@@ -500,7 +500,7 @@ suite('TextAreaState', () => {
 
 		function testPagedScreenReaderStrategy(lines: string[], selection: Selection, expected: TextAreaState): void {
 			const model = Model.createFromString(lines.join('\n'));
-			const actual = PagedScreenReaderStrategy.fromEditorSelection(TextAreaState.EMPTY, model, selection);
+			const actual = PagedScreenReaderStrategy.fromEditorSelection(TextAreaState.EMPTY, model, selection, true);
 			assert.ok(actual.equals(expected));
 			model.dispose();
 		}