migrate tests to nullsafe (#25616)

lib/web_ui/test/golden_tests/engine/backdrop_filter_golden_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:html' as html;
 
 import 'package:test/bootstrap/browser.dart';
@@ -56,9 +55,9 @@ void testMain() async {
     builder.pop();
     builder.pop();
 
-    html.document.body.append(builder
+    html.document.body!.append(builder
         .build()
-        .webOnlyRootElement);
+        .webOnlyRootElement!);
 
     await matchGoldenFile('backdrop_filter_clip.png', region: region,
         maxDiffRatePercent: 0.8);
@@ -107,9 +106,9 @@ void testMain() async {
     builder2.pop();
     builder2.pop();
 
-    html.document.body.append(builder2
+    html.document.body!.append(builder2
         .build()
-        .webOnlyRootElement);
+        .webOnlyRootElement!);
 
     await matchGoldenFile('backdrop_filter_clip_moved.png', region: region,
       maxDiffRatePercent: 0.8);
@@ -139,9 +138,9 @@ void testMain() async {
     builder.pop();
     builder.pop();
 
-    html.document.body.append(builder
+    html.document.body!.append(builder
         .build()
-        .webOnlyRootElement);
+        .webOnlyRootElement!);
 
     await matchGoldenFile('backdrop_filter_no_child_rendering.png', region: region,
         maxDiffRatePercent: 0.8);
@@ -149,39 +148,39 @@ void testMain() async {
 }
 
 Picture _drawTestPictureWithCircles(Rect region, double offsetX, double offsetY) {
-  final EnginePictureRecorder recorder = PictureRecorder();
+  final EnginePictureRecorder recorder = PictureRecorder() as EnginePictureRecorder;
   final RecordingCanvas canvas =
   recorder.beginRecording(region);
   canvas.drawCircle(
-      Offset(offsetX + 10, offsetY + 10), 10, Paint()..style = PaintingStyle.fill);
+      Offset(offsetX + 10, offsetY + 10), 10, SurfacePaint()..style = PaintingStyle.fill);
   canvas.drawCircle(
       Offset(offsetX + 60, offsetY + 10),
       10,
-      Paint()
+      SurfacePaint()
         ..style = PaintingStyle.fill
         ..color = const Color.fromRGBO(255, 0, 0, 1));
   canvas.drawCircle(
       Offset(offsetX + 10, offsetY + 60),
       10,
-      Paint()
+      SurfacePaint()
         ..style = PaintingStyle.fill
         ..color = const Color.fromRGBO(0, 255, 0, 1));
   canvas.drawCircle(
       Offset(offsetX + 60, offsetY + 60),
       10,
-      Paint()
+      SurfacePaint()
         ..style = PaintingStyle.fill
         ..color = const Color.fromRGBO(0, 0, 255, 1));
   return recorder.endRecording();
 }
 
 Picture _drawBackground(Rect region) {
-  final EnginePictureRecorder recorder = PictureRecorder();
+  final EnginePictureRecorder recorder = PictureRecorder() as EnginePictureRecorder;
   final RecordingCanvas canvas =
   recorder.beginRecording(region);
   canvas.drawRect(
       region.deflate(8.0),
-      Paint()
+      SurfacePaint()
         ..style = PaintingStyle.fill
         ..color = Color(0xFFE0FFE0)
       );

lib/web_ui/test/golden_tests/engine/canvas_arc_golden_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:html' as html;
 import 'dart:math' as math;
 import 'package:test/bootstrap/browser.dart';
@@ -19,7 +18,7 @@ void main() {
 void testMain() async {
   final Rect region = Rect.fromLTWH(0, 0, 400, 600);
 
-  BitmapCanvas canvas;
+  late BitmapCanvas canvas;
 
   setUp(() {
     canvas = BitmapCanvas(region, RenderStrategy());
@@ -48,7 +47,7 @@ void testMain() async {
         largeArc: true, clockwise: true, distance: -20);
 
 
-    html.document.body.append(canvas.rootElement);
+    html.document.body!.append(canvas.rootElement);
     await matchGoldenFile('canvas_arc_to_point.png', region: region);
   });
 
@@ -63,7 +62,7 @@ void testMain() async {
       ..color = Color(0xFFFF9800) // orange
       ..style = PaintingStyle.fill);
 
-    html.document.body.append(canvas.rootElement);
+    html.document.body!.append(canvas.rootElement);
     await matchGoldenFile('canvas_addarc.png', region: region);
   });
 
@@ -81,7 +80,7 @@ void testMain() async {
       ..color = Color(0xFFFF9800) // orange
       ..style = PaintingStyle.fill);
 
-    html.document.body.append(canvas.rootElement);
+    html.document.body!.append(canvas.rootElement);
     await matchGoldenFile('canvas_addarc_ccw.png', region: region);
   });
 }

lib/web_ui/test/golden_tests/engine/canvas_blend_golden_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:html' as html;
 import 'dart:js_util' as js_util;
 
@@ -35,7 +34,7 @@ void testMain() async {
     final html.Element sceneElement = html.Element.tag('flt-scene');
     try {
       sceneElement.append(engineCanvas.rootElement);
-      html.document.body.append(sceneElement);
+      html.document.body!.append(sceneElement);
       await matchGoldenFile('$fileName.png', region: region,
           maxDiffRatePercent: maxDiffRatePercent, write: write);
     } finally {
@@ -58,13 +57,13 @@ void testMain() async {
     rc.save();
     rc.drawRect(
         Rect.fromLTRB(0, 0, 400, 400),
-        Paint()
+        SurfacePaint()
           ..style = PaintingStyle.fill
           ..color = const Color.fromARGB(255, 255, 255, 255));
     rc.drawCircle(
         Offset(100, 100),
         80.0,
-        Paint()
+        SurfacePaint()
           ..style = PaintingStyle.fill
           ..color = const Color.fromARGB(128, 255, 0, 0)
           ..blendMode = BlendMode.difference);
@@ -72,7 +71,7 @@ void testMain() async {
     rc.drawCircle(
         Offset(170, 100),
         80.0,
-        Paint()
+        SurfacePaint()
           ..style = PaintingStyle.fill
           ..blendMode = BlendMode.color
           ..color = const Color.fromARGB(128, 0, 255, 0));
@@ -80,7 +79,7 @@ void testMain() async {
     rc.drawCircle(
         Offset(135, 170),
         80.0,
-        Paint()
+        SurfacePaint()
           ..style = PaintingStyle.fill
           ..color = const Color.fromARGB(128, 255, 0, 0));
     rc.restore();
@@ -95,20 +94,20 @@ void testMain() async {
     rc.save();
     rc.drawRect(
         Rect.fromLTRB(0, 0, 400, 400),
-        Paint()
+        SurfacePaint()
           ..style = PaintingStyle.fill
           ..color = const Color.fromARGB(255, 255, 255, 255));
     rc.drawCircle(
         Offset(100, 100),
         80.0,
-        Paint()
+        SurfacePaint()
           ..style = PaintingStyle.fill
           ..color = const Color.fromARGB(128, 255, 0, 0)
           ..blendMode = BlendMode.difference);
     rc.drawCircle(
         Offset(170, 100),
         80.0,
-        Paint()
+        SurfacePaint()
           ..style = PaintingStyle.fill
           ..blendMode = BlendMode.color
           ..color = const Color.fromARGB(128, 0, 255, 0));
@@ -116,11 +115,11 @@ void testMain() async {
     rc.drawCircle(
         Offset(135, 170),
         80.0,
-        Paint()
+        SurfacePaint()
           ..style = PaintingStyle.fill
           ..color = const Color.fromARGB(128, 255, 0, 0));
     rc.drawImage(createTestImage(), Offset(135.0, 130.0),
-        Paint()..blendMode = BlendMode.multiply);
+        SurfacePaint()..blendMode = BlendMode.multiply);
     rc.restore();
     await _checkScreenshot(rc, 'canvas_blend_image_multiply',
         maxDiffRatePercent: operatingSystem == OperatingSystem.macOs ? 2.95 :

lib/web_ui/test/golden_tests/engine/canvas_clip_path_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:html' as html;
 import 'dart:js_util' as js_util;
 
@@ -42,7 +41,7 @@ void testMain() async {
     path.addOval(Rect.fromLTWH(100, 30, testWidth, testHeight));
     rc.clipPath(path);
     rc.drawImageRect(testImage, Rect.fromLTRB(0, 0, testWidth, testHeight),
-        Rect.fromLTWH(100, 30, testWidth, testHeight), Paint());
+        Rect.fromLTWH(100, 30, testWidth, testHeight), engine.SurfacePaint());
     rc.restore();
     await canvasScreenshot(rc, 'image_clipped_by_oval',
       region: screenRect);
@@ -65,7 +64,7 @@ void testMain() async {
     paintPath.close();
     rc.drawPath(
         paintPath,
-        Paint()
+        engine.SurfacePaint()
           ..color = Color(0xFF00FF00)
           ..style = PaintingStyle.fill);
     rc.restore();
@@ -85,7 +84,7 @@ void testMain() async {
     paintPath.addRect(Rect.fromLTWH(-50, 0, testWidth, testHeight));
     paintPath.close();
     rc.drawPath(paintPath,
-        Paint()
+        engine.SurfacePaint()
           ..color = Color(0xFF000000)
           ..style = PaintingStyle.stroke);
 
@@ -96,7 +95,7 @@ void testMain() async {
     path.close();
     rc.clipPath(path);
     rc.drawImageRect(createTestImage(), Rect.fromLTRB(0, 0, testWidth, testHeight),
-        Rect.fromLTWH(-50, 0, testWidth, testHeight), Paint());
+        Rect.fromLTWH(-50, 0, testWidth, testHeight), engine.SurfacePaint());
     rc.restore();
     await canvasScreenshot(rc, 'image_clipped_by_triangle_off_screen');
   });
@@ -113,7 +112,7 @@ void testMain() async {
     paintPath.addRect(Rect.fromLTWH(-50, 0, testWidth, testHeight));
     paintPath.close();
     rc.drawPath(paintPath,
-        Paint()
+        engine.SurfacePaint()
           ..color = Color(0xFF000000)
           ..style = PaintingStyle.stroke);
 
@@ -121,7 +120,7 @@ void testMain() async {
     path.addOval(Rect.fromLTRB(-200, 0, 100, 150));
     rc.clipPath(path);
     rc.drawImageRect(createTestImage(), Rect.fromLTRB(0, 0, testWidth, testHeight),
-        Rect.fromLTWH(-50, 0, testWidth, testHeight), Paint());
+        Rect.fromLTWH(-50, 0, testWidth, testHeight), engine.SurfacePaint());
     rc.restore();
     await canvasScreenshot(rc, 'image_clipped_by_oval_path');
   });

lib/web_ui/test/golden_tests/engine/canvas_context_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:html' as html;
 
 import 'package:test/bootstrap/browser.dart';
@@ -35,7 +34,7 @@ void testMain() async {
     final html.Element sceneElement = html.Element.tag('flt-scene');
     try {
       sceneElement.append(engineCanvas.rootElement);
-      html.document.body.append(sceneElement);
+      html.document.body!.append(sceneElement);
       // TODO(yjbanov): 10% diff rate is excessive. Update goldens.
       await matchGoldenFile('$fileName.png', region: region, maxDiffRatePercent: 10);
     } finally {
@@ -57,7 +56,7 @@ void testMain() async {
   test('Clips image with oval clip path', () async {
     final engine.RecordingCanvas rc =
         engine.RecordingCanvas(const Rect.fromLTRB(0, 0, 400, 300));
-    final Paint paint = Paint()
+    final engine.SurfacePaint paint = Paint() as engine.SurfacePaint
       ..color = Color(0xFF00FF00)
       ..style = PaintingStyle.fill;
     rc.save();
@@ -98,11 +97,11 @@ void testMain() async {
     rc.save();
     rc.restore();
     // The rectangle should be clipped against oval.
-    rc.drawRect(Rect.fromLTWH(0, 0, 300, 300), badPaint);
+    rc.drawRect(Rect.fromLTWH(0, 0, 300, 300), badPaint as engine.SurfacePaint);
     rc.restore();
     // The rectangle should paint without clipping since we restored
     // context.
-    rc.drawRect(Rect.fromLTWH(0, 0, 200, 200), goodPaint);
+    rc.drawRect(Rect.fromLTWH(0, 0, 200, 200), goodPaint as engine.SurfacePaint);
     await _checkScreenshot(rc, 'context_save_restore_clip');
   });
 }

lib/web_ui/test/golden_tests/engine/screenshot.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:html' as html;
 import 'package:ui/ui.dart' as ui;
 import 'package:ui/src/engine.dart';
@@ -23,7 +22,7 @@ Future<void> canvasScreenshot(RecordingCanvas rc, String fileName,
   final html.Element sceneElement = html.Element.tag('flt-scene');
   try {
     sceneElement.append(engineCanvas.rootElement);
-    html.document.body.append(sceneElement);
+    html.document.body!.append(sceneElement);
     await matchGoldenFile('$fileName.png',
         region: region, maxDiffRatePercent: maxDiffRatePercent, write: write);
   } finally {

lib/web_ui/test/golden_tests/golden_failure_smoke_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:html' as html;
 
 import 'package:test/bootstrap/browser.dart';
@@ -16,7 +15,7 @@ void main() {
 
 void testMain() {
   test('screenshot test reports failure', () async {
-    html.document.body.innerHtml = 'Text that does not appear on the screenshot!';
+    html.document.body!.innerHtml = 'Text that does not appear on the screenshot!';
     await matchGoldenFile('__local__/smoke_test.png', region: Rect.fromLTWH(0, 0, 320, 200));
   });
 }

lib/web_ui/test/golden_tests/golden_success_smoke_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:html' as html;
 
 import 'package:test/bootstrap/browser.dart';
@@ -20,8 +19,8 @@ void testMain() async {
   await webOnlyInitializePlatform(assetManager: WebOnlyMockAssetManager());
 
   test('screenshot test reports success', () async {
-    html.document.body.style.fontFamily = 'Roboto';
-    html.document.body.innerHtml = 'Hello world!';
+    html.document.body!.style.fontFamily = 'Roboto';
+    html.document.body!.innerHtml = 'Hello world!';
     // TODO: https://github.com/flutter/flutter/issues/74702 , reduce webkit percentage.
     await matchGoldenFile('__local__/smoke_test.png', region: Rect.fromLTWH(0, 0, 320, 200),
       maxDiffRatePercent: browserEngine == BrowserEngine.webkit ? 3.0 : 0.28);