[web] more null-safe tests (flutter#26712)

lib/web_ui/test/canvaskit/vertices_test.dart

@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.6
 import 'package:test/bootstrap/browser.dart';
 import 'package:test/test.dart';
 import 'package:ui/src/engine.dart';
@@ -29,15 +28,15 @@ void testMain() {
       canvas.drawVertices(
         vertices,
         ui.BlendMode.srcOver,
-        ui.Paint(),
+        CkPaint(),
       );
       vertices.delete();
     });
   // TODO: https://github.com/flutter/flutter/issues/60040
   }, skip: isIosSafari);
 }
 
-ui.Vertices _testVertices() {
+CkVertices _testVertices() {
   return ui.Vertices(
     ui.VertexMode.triangles,
     <ui.Offset>[
@@ -56,5 +55,5 @@ ui.Vertices _testVertices() {
       ui.Color.fromRGBO(0, 0, 255, 1.0),
     ],
     indices: <int>[0, 1, 2],
-  );
+  ) as CkVertices;
 }

lib/web_ui/test/engine/image/html_image_codec_test.dart

@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.6
 import 'dart:async';
 import 'dart:typed_data';
 
@@ -103,7 +102,7 @@ void testMain() async {
   group('ImageCodecUrl', () {
     test('loads sample image from web', () async {
       final Uri uri = Uri.base.resolve('sample_image1.png');
-      final HtmlCodec codec = await ui.webOnlyInstantiateImageCodecFromUrl(uri);
+      final HtmlCodec codec = await ui.webOnlyInstantiateImageCodecFromUrl(uri) as HtmlCodec;
       final ui.FrameInfo frameInfo = await codec.getNextFrame();
       expect(frameInfo.image, isNotNull);
       expect(frameInfo.image.width, 100);
@@ -114,7 +113,7 @@ void testMain() async {
       final HtmlCodec codec = await ui.webOnlyInstantiateImageCodecFromUrl(uri,
           chunkCallback: (int loaded, int total) {
         buffer.write('$loaded/$total,');
-      });
+      }) as HtmlCodec;
       await codec.getNextFrame();
       expect(buffer.toString(), '0/100,100/100,');
     });

lib/web_ui/test/engine/semantics/accessibility_test.dart

@@ -2,15 +2,14 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.6
 import 'dart:async' show Future;
 import 'dart:html';
 
 import 'package:test/bootstrap/browser.dart';
 import 'package:test/test.dart';
 import 'package:ui/src/engine.dart';
 
-const MessageCodec<dynamic> codec = StandardMessageCodec();
+const StandardMessageCodec codec = StandardMessageCodec();
 const String testMessage = 'This is an tooltip.';
 const Map<dynamic, dynamic> testInput = <dynamic, dynamic>{
   'data': <dynamic, dynamic>{'message': testMessage}
@@ -21,7 +20,7 @@ void main() {
 }
 
 void testMain() {
-  AccessibilityAnnouncements accessibilityAnnouncements;
+  late AccessibilityAnnouncements accessibilityAnnouncements;
 
   group('$AccessibilityAnnouncements', () {
     setUp(() {
@@ -45,7 +44,7 @@ void testMain() {
         isNotNull,
       );
       final LabelElement input =
-          document.getElementById('accessibility-element');
+          document.getElementById('accessibility-element') as LabelElement;
       expect(input.getAttribute('aria-live'), equals('polite'));
       expect(input.text, testMessage);
 

lib/web_ui/test/engine/semantics/semantics_test.dart

@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.9
 @TestOn('chrome || safari || firefox')
 
 import 'dart:async';
@@ -88,7 +87,7 @@ void _testEngineSemanticsOwner() {
 
     // Synthesize a click on the placeholder.
     final html.Element placeholder =
-        appShadowRoot.querySelector('flt-semantics-placeholder');
+        appShadowRoot.querySelector('flt-semantics-placeholder')!;
 
     expect(placeholder.isConnected, isTrue);
 
@@ -101,7 +100,7 @@ void _testEngineSemanticsOwner() {
 
     // On mobile semantics is enabled asynchronously.
     if (isMobile) {
-      while (placeholder.isConnected) {
+      while (placeholder.isConnected!) {
         await Future<void>.delayed(const Duration(milliseconds: 50));
       }
     }
@@ -114,7 +113,7 @@ void _testEngineSemanticsOwner() {
     expect(semantics().semanticsEnabled, isFalse);
 
     final html.Element placeholder =
-        appShadowRoot.querySelector('flt-semantics-placeholder');
+        appShadowRoot.querySelector('flt-semantics-placeholder')!;
 
     expect(placeholder.isConnected, isTrue);
 
@@ -159,12 +158,12 @@ void _testEngineSemanticsOwner() {
     // Create
     renderLabel('Hello');
 
-    final Map<int, SemanticsObject> tree = semantics().debugSemanticsTree;
+    final Map<int, SemanticsObject> tree = semantics().debugSemanticsTree!;
     expect(tree.length, 2);
-    expect(tree[0].id, 0);
-    expect(tree[0].element.tagName.toLowerCase(), 'flt-semantics');
-    expect(tree[1].id, 1);
-    expect(tree[1].label, 'Hello');
+    expect(tree[0]!.id, 0);
+    expect(tree[0]!.element.tagName.toLowerCase(), 'flt-semantics');
+    expect(tree[1]!.id, 1);
+    expect(tree[1]!.label, 'Hello');
 
     expectSemanticsTree('''
 <sem style="$rootSemanticStyle">
@@ -383,9 +382,9 @@ void _testContainer() {
 </sem>''');
 
     final html.Element parentElement =
-        appShadowRoot.querySelector('flt-semantics');
+        appShadowRoot.querySelector('flt-semantics')!;
     final html.Element container =
-        appShadowRoot.querySelector('flt-semantics-container');
+        appShadowRoot.querySelector('flt-semantics-container')!;
 
     if (isMacOrIOS) {
       expect(parentElement.style.top, '0px');
@@ -431,9 +430,9 @@ void _testContainer() {
 </sem>''');
 
     final html.Element parentElement =
-        appShadowRoot.querySelector('flt-semantics');
+        appShadowRoot.querySelector('flt-semantics')!;
     final html.Element container =
-        appShadowRoot.querySelector('flt-semantics-container');
+        appShadowRoot.querySelector('flt-semantics-container')!;
 
     expect(parentElement.style.transform, 'matrix(1, 0, 0, 1, 10, 10)');
     expect(parentElement.style.transformOrigin, '0px 0px 0px');
@@ -477,9 +476,9 @@ void _testContainer() {
     }
 
     final html.Element parentElement =
-        appShadowRoot.querySelector('flt-semantics');
+        appShadowRoot.querySelector('flt-semantics')!;
     final html.Element container =
-        appShadowRoot.querySelector('flt-semantics-container');
+        appShadowRoot.querySelector('flt-semantics-container')!;
 
     if (isMacOrIOS) {
       expect(parentElement.style.top, '0px');
@@ -550,12 +549,12 @@ void _testVerticalScrolling() {
   </sem-c>
 </sem>''');
 
-    final html.Element scrollable = findScrollable();
+    final html.Element? scrollable = findScrollable();
     expect(scrollable, isNotNull);
 
     // When there's less content than the available size the neutral scrollTop
     // is 0.
-    expect(scrollable.scrollTop, 0);
+    expect(scrollable!.scrollTop, 0);
 
     semantics().semanticsEnabled = false;
   });
@@ -574,7 +573,7 @@ void _testVerticalScrolling() {
     final Zone testZone = Zone.current;
 
     ui.window.onSemanticsAction =
-        (int id, ui.SemanticsAction action, ByteData args) {
+        (int id, ui.SemanticsAction action, ByteData? args) {
       idLogController.add(id);
       actionLogController.add(action);
       testZone.run(() {
@@ -620,7 +619,7 @@ void _testVerticalScrolling() {
   </sem-c>
 </sem>''');
 
-    final html.Element scrollable = findScrollable();
+    final html.Element? scrollable = findScrollable();
     expect(scrollable, isNotNull);
 
     // When there's more content than the available size the neutral scrollTop
@@ -633,7 +632,7 @@ void _testVerticalScrolling() {
       browserMaxScrollDiff = 1;
     }
 
-    expect(scrollable.scrollTop >= (10 - browserMaxScrollDiff), isTrue);
+    expect(scrollable!.scrollTop >= (10 - browserMaxScrollDiff), isTrue);
 
     scrollable.scrollTop = 20;
     expect(scrollable.scrollTop, 20);
@@ -702,12 +701,12 @@ void _testHorizontalScrolling() {
   </sem-c>
 </sem>''');
 
-    final html.Element scrollable = findScrollable();
+    final html.Element? scrollable = findScrollable();
     expect(scrollable, isNotNull);
 
     // When there's less content than the available size the neutral
     // scrollLeft is 0.
-    expect(scrollable.scrollLeft, 0);
+    expect(scrollable!.scrollLeft, 0);
 
     semantics().semanticsEnabled = false;
   });
@@ -753,7 +752,7 @@ void _testHorizontalScrolling() {
   </sem-c>
 </sem>''');
 
-    final html.Element scrollable = findScrollable();
+    final html.Element? scrollable = findScrollable();
     expect(scrollable, isNotNull);
 
     // When there's more content than the available size the neutral scrollTop
@@ -765,7 +764,7 @@ void _testHorizontalScrolling() {
         operatingSystem == OperatingSystem.macOs) {
       browserMaxScrollDiff = 1;
     }
-    expect(scrollable.scrollLeft >= (10 - browserMaxScrollDiff), isTrue);
+    expect(scrollable!.scrollLeft >= (10 - browserMaxScrollDiff), isTrue);
 
     scrollable.scrollLeft = 20;
     expect(scrollable.scrollLeft, 20);
@@ -835,7 +834,7 @@ void _testIncrementables() {
   <input aria-valuenow="1" aria-valuetext="d" aria-valuemax="2" aria-valuemin="1">
 </sem>''');
 
-    final html.InputElement input = appShadowRoot.querySelector('input');
+    final html.InputElement input = appShadowRoot.querySelector('input') as html.InputElement;
     input.value = '2';
     input.dispatchEvent(html.Event('change'));
 
@@ -869,7 +868,7 @@ void _testIncrementables() {
   <input aria-valuenow="1" aria-valuetext="d" aria-valuemax="1" aria-valuemin="0">
 </sem>''');
 
-    final html.InputElement input = appShadowRoot.querySelector('input');
+    final html.InputElement input = appShadowRoot.querySelector('input') as html.InputElement;
     input.value = '0';
     input.dispatchEvent(html.Event('change'));
 
@@ -963,7 +962,7 @@ void _testTextField() {
     semantics().updateSemantics(builder.build());
 
     final html.Element textField =
-        appShadowRoot.querySelector('input[data-semantics-role="text-field"]');
+        appShadowRoot.querySelector('input[data-semantics-role="text-field"]')!;
 
     expect(appShadowRoot.activeElement, isNot(textField));
 
@@ -1491,10 +1490,10 @@ void updateNode(
   String increasedValue = '',
   String decreasedValue = '',
   ui.TextDirection textDirection = ui.TextDirection.ltr,
-  Float64List transform,
-  Int32List childrenInTraversalOrder,
-  Int32List childrenInHitTestOrder,
-  Int32List additionalActions,
+  Float64List? transform,
+  Int32List? childrenInTraversalOrder,
+  Int32List? childrenInHitTestOrder,
+  Int32List? additionalActions,
 }) {
   transform ??= Float64List.fromList(Matrix4.identity().storage);
   childrenInTraversalOrder ??= Int32List(0);

lib/web_ui/test/engine/services/serialization_test.dart

@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.6
 import 'dart:typed_data';
 
 import 'package:test/test.dart';

lib/web_ui/test/engine/surface/frame_timings_test.dart

@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.6
 import 'package:test/bootstrap/browser.dart';
 import 'package:test/test.dart';
 import 'package:ui/src/engine.dart';
@@ -15,7 +14,7 @@ void main() {
 
 void testMain() {
   setUp(() async {
-    await initializeEngine();
+    initializeEngine();
   });
 
   test('collects frame timings', () async {

lib/web_ui/test/engine/surface/platform_view_test.dart

@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.6
 import 'dart:async';
 import 'dart:html' as html;
 
@@ -22,7 +21,7 @@ void main() {
 }
 
 void testMain() {
-  PersistedPlatformView view;
+  late PersistedPlatformView view;
 
   group('PersistedPlatformView', () {
     setUp(() async {

lib/web_ui/test/engine/surface/shaders/normalized_gradient_test.dart

@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.6
 import 'package:test/bootstrap/browser.dart';
 import 'package:test/test.dart';
 import 'package:ui/src/engine/html/shaders/normalized_gradient.dart';

lib/web_ui/test/engine/surface/shaders/shader_builder_test.dart

@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.6
 import 'package:test/bootstrap/browser.dart';
 import 'package:test/test.dart';
 import 'package:ui/src/engine.dart';
@@ -25,7 +24,7 @@ void testMain() {
       ')';
 
   setUpAll(() async {
-    await webOnlyInitializeEngine();
+    webOnlyInitializeEngine();
   });
 
   group('Shader Declarations', () {