fix https://github.com/microsoft/vscode/issues/177591 (#200040)

src/vs/editor/contrib/suggest/browser/suggestController.ts

@@ -353,7 +353,17 @@ export class SuggestController implements IEditorContribution {
 			const scrollState = StableEditorScrollState.capture(this.editor);
 			this.editor.executeEdits(
 				'suggestController.additionalTextEdits.sync',
-				item.completion.additionalTextEdits.map(edit => EditOperation.replaceMove(Range.lift(edit.range), edit.text))
+				item.completion.additionalTextEdits.map(edit => {
+					let range = Range.lift(edit.range);
+					if (range.startLineNumber === item.position.lineNumber && range.startColumn > item.position.column) {
+						// shift additional edit when it is "after" the completion insertion position
+						const columnDelta = this.editor.getPosition()!.column - item.position.column;
+						const startColumnDelta = columnDelta;
+						const endColumnDelta = Range.spansMultipleLines(range) ? 0 : columnDelta;
+						range = new Range(range.startLineNumber, range.startColumn + startColumnDelta, range.endLineNumber, range.endColumn + endColumnDelta);
+					}
+					return EditOperation.replaceMove(range, edit.text);
+				})
 			);
 			scrollState.restoreRelativeVerticalPositionOfCursor(this.editor);
 

src/vs/editor/contrib/suggest/test/browser/suggestController.test.ts

@@ -616,4 +616,56 @@ suite('SuggestController', function () {
 
 		await p2;
 	});
+
+	test('Ranges where additionalTextEdits are applied are not appropriate when characters are typed #177591', async function () {
+		disposables.add(languageFeaturesService.completionProvider.register({ scheme: 'test-ctrl' }, {
+			_debugDisplayName: 'test',
+			provideCompletionItems(doc, pos) {
+				return {
+					suggestions: [{
+						kind: CompletionItemKind.Snippet,
+						label: 'aaa',
+						insertText: 'aaa',
+						range: Range.fromPositions(pos),
+						additionalTextEdits: [{
+							range: Range.fromPositions(pos.delta(0, 10)),
+							text: 'aaa'
+						}]
+					}]
+				};
+			}
+		}));
+
+		{ // PART1 - no typing
+			editor.setValue(`123456789123456789`);
+			editor.setSelection(new Selection(1, 1, 1, 1));
+			const p1 = Event.toPromise(controller.model.onDidSuggest);
+			controller.triggerSuggest();
+
+			const e = await p1;
+			assert.strictEqual(e.completionModel.items.length, 1);
+			assert.strictEqual(e.completionModel.items[0].textLabel, 'aaa');
+
+			controller.acceptSelectedSuggestion(false, false);
+
+			assert.strictEqual(editor.getValue(), 'aaa1234567891aaa23456789');
+		}
+
+		{ // PART2 - typing
+			editor.setValue(`123456789123456789`);
+			editor.setSelection(new Selection(1, 1, 1, 1));
+			const p1 = Event.toPromise(controller.model.onDidSuggest);
+			controller.triggerSuggest();
+
+			const e = await p1;
+			assert.strictEqual(e.completionModel.items.length, 1);
+			assert.strictEqual(e.completionModel.items[0].textLabel, 'aaa');
+
+			editor.trigger('keyboard', 'type', { text: 'aa' });
+
+			controller.acceptSelectedSuggestion(false, false);
+
+			assert.strictEqual(editor.getValue(), 'aaa1234567891aaa23456789');
+		}
+	});
 });