Flutter_driver nnbd (#74856)

dev/bots/test.dart

@@ -669,7 +669,7 @@ Future<void> _runFrameworkTests() async {
     await _runFlutterTest(path.join(flutterRoot, 'examples', 'hello_world'), options: soundNullSafetyOptions);
     await _runFlutterTest(path.join(flutterRoot, 'examples', 'layers'), options: soundNullSafetyOptions);
     await _runFlutterTest(path.join(flutterRoot, 'dev', 'benchmarks', 'test_apps', 'stocks'));
-    await _runFlutterTest(path.join(flutterRoot, 'packages', 'flutter_driver'), tests: <String>[path.join('test', 'src', 'real_tests')]);
+    await _runFlutterTest(path.join(flutterRoot, 'packages', 'flutter_driver'), tests: <String>[path.join('test', 'src', 'real_tests')], options: soundNullSafetyOptions);
     await _runFlutterTest(path.join(flutterRoot, 'packages', 'integration_test'));
     await _runFlutterTest(path.join(flutterRoot, 'packages', 'flutter_goldens'), options: soundNullSafetyOptions);
     await _runFlutterTest(path.join(flutterRoot, 'packages', 'flutter_localizations'), options: soundNullSafetyOptions);

packages/flutter_driver/lib/flutter_driver.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 /// Provides API to test Flutter applications that run on real
 /// devices and emulators.
 ///

packages/flutter_driver/lib/src/common/error.dart

@@ -14,10 +14,10 @@ class DriverError extends Error {
   final String message;
 
   /// The error object that was caught and wrapped by this error object, if any.
-  final dynamic originalError;
+  final Object? originalError;
 
   /// The stack trace that was caught and wrapped by this error object, if any.
-  final dynamic originalStackTrace;
+  final Object? originalStackTrace;
 
   @override
   String toString() {

packages/flutter_driver/lib/src/common/fuchsia_compat.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 /// Convenience methods for Flutter application driving on Fuchsia. Can
 /// be run on either a host machine (making a remote connection to a Fuchsia
 /// device), or on the target Fuchsia machine.
@@ -40,13 +38,13 @@ class _DummySshCommandRunner implements SshCommandRunner {
   }
 
   @override
-  String get sshConfigPath => null;
+  String get sshConfigPath => '';
 
   @override
   String get address => InternetAddress.loopbackIPv4.address;
 
   @override
-  String get interface => null;
+  String get interface => '';
 
   @override
   Future<List<String>> run(String command) async {
@@ -72,8 +70,8 @@ class _DummySshCommandRunner implements SshCommandRunner {
 Future<PortForwarder> _dummyPortForwardingFunction(
   String address,
   int remotePort, [
-  String interface = '',
-  String configFile,
+  String? interface,
+  String? configFile,
 ]) async {
   return _DummyPortForwarder(remotePort, remotePort);
 }

packages/flutter_driver/lib/src/driver/common.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import 'dart:io' show Platform;
 
 import 'package:file/file.dart';

packages/flutter_driver/lib/src/driver/percentile_utils.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 /// Returns the [p]-th percentile element from the [doubles].
 /// `List<doubles>` will be sorted.
 double findPercentile(List<double> doubles, double p) {

packages/flutter_driver/lib/src/driver/profiling_summarizer.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import 'percentile_utils.dart';
 import 'timeline.dart';
 
@@ -63,7 +61,7 @@ class ProfilingSummarizer {
       assert(kProfilingEvents.contains(event.name));
       final ProfileType type = _getProfileType(event.name);
       eventsByType[type] ??= <TimelineEvent>[];
-      eventsByType[type].add(event);
+      eventsByType[type]!.add(event);
     }
     return ProfilingSummarizer._(eventsByType);
   }
@@ -96,7 +94,7 @@ class ProfilingSummarizer {
   /// Returns true if there are events in the timeline corresponding to [profileType].
   bool hasProfilingInfo(ProfileType profileType) {
     if (eventByType.containsKey(profileType)) {
-      return eventByType[profileType].isNotEmpty;
+      return eventByType[profileType]!.isNotEmpty;
     } else {
       return false;
     }
@@ -104,7 +102,7 @@ class ProfilingSummarizer {
 
   /// Computes the average of the `profileType` over the recorded events.
   double computeAverage(ProfileType profileType) {
-    final List<TimelineEvent> events = eventByType[profileType];
+    final List<TimelineEvent> events = eventByType[profileType]!;
     assert(events.isNotEmpty);
     final double total = events
         .map((TimelineEvent e) => _getProfileValue(profileType, e))
@@ -114,7 +112,7 @@ class ProfilingSummarizer {
 
   /// The [percentile]-th percentile `profileType` over the recorded events.
   double computePercentile(ProfileType profileType, double percentile) {
-    final List<TimelineEvent> events = eventByType[profileType];
+    final List<TimelineEvent> events = eventByType[profileType]!;
     assert(events.isNotEmpty);
     final List<double> doubles = events
         .map((TimelineEvent e) => _getProfileValue(profileType, e))
@@ -122,7 +120,7 @@ class ProfilingSummarizer {
     return findPercentile(doubles, percentile);
   }
 
-  static ProfileType _getProfileType(String eventName) {
+  static ProfileType _getProfileType(String? eventName) {
     switch (eventName) {
       case _kCpuProfile:
         return ProfileType.CPU;
@@ -147,13 +145,11 @@ class ProfilingSummarizer {
             _getArgValue('owned_shared_memory_usage', e);
         return dirtyMem + ownedSharedMem;
     }
-
-    throw Exception('Invalid $profileType.');
   }
 
   double _getArgValue(String argKey, TimelineEvent e) {
-    assert(e.arguments.containsKey(argKey));
-    final dynamic argVal = e.arguments[argKey];
+    assert(e.arguments!.containsKey(argKey));
+    final dynamic argVal = e.arguments![argKey];
     assert(argVal is String);
     return double.parse(argVal as String);
   }

packages/flutter_driver/lib/src/driver/scene_display_lag_summarizer.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import 'percentile_utils.dart';
 import 'timeline.dart';
 
@@ -68,8 +66,8 @@ class SceneDisplayLagSummarizer {
 
   double _getVsyncTransitionsMissed(TimelineEvent e) {
     assert(e.name == kSceneDisplayLagEvent);
-    assert(e.arguments.containsKey(_kVsyncTransitionsMissed));
-    final dynamic transitionsMissed = e.arguments[_kVsyncTransitionsMissed];
+    assert(e.arguments!.containsKey(_kVsyncTransitionsMissed));
+    final dynamic transitionsMissed = e.arguments![_kVsyncTransitionsMissed];
     assert(transitionsMissed is String);
     return double.parse(transitionsMissed as String);
   }

packages/flutter_driver/lib/src/driver/timeline.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 /// Timeline data recorded by the Flutter runtime.
 class Timeline {
   /// Creates a timeline given JSON-encoded timeline data.
@@ -25,27 +23,29 @@ class Timeline {
   ///
   /// This is parsed from "traceEvents" data within [json] and sorted by
   /// timestamp. Anything without a valid timestamp is put in the beginning.
-  final List<TimelineEvent> events;
+  ///
+  /// This will be null if there are are no "traceEvents" in the [json].
+  final List<TimelineEvent>? events;
 }
 
 /// A single timeline event.
 class TimelineEvent {
   /// Creates a timeline event given JSON-encoded event data.
   TimelineEvent(this.json)
-      : name = json['name'] as String,
-        category = json['cat'] as String,
-        phase = json['ph'] as String,
-        processId = json['pid'] as int,
-        threadId = json['tid'] as int,
+      : name = json['name'] as String?,
+        category = json['cat'] as String?,
+        phase = json['ph'] as String?,
+        processId = json['pid'] as int?,
+        threadId = json['tid'] as int?,
         duration = json['dur'] != null
             ? Duration(microseconds: json['dur'] as int)
             : null,
         threadDuration = json['tdur'] != null
             ? Duration(microseconds: json['tdur'] as int)
             : null,
-        timestampMicros = json['ts'] as int,
-        threadTimestampMicros = json['tts'] as int,
-        arguments = json['args'] as Map<String, dynamic>;
+        timestampMicros = json['ts'] as int?,
+        threadTimestampMicros = json['tts'] as int?,
+        arguments = json['args'] as Map<String, dynamic>?;
 
   /// The original event JSON.
   final Map<String, dynamic> json;
@@ -53,28 +53,28 @@ class TimelineEvent {
   /// The name of the event.
   ///
   /// Corresponds to the "name" field in the JSON event.
-  final String name;
+  final String? name;
 
   /// Event category. Events with different names may share the same category.
   ///
   /// Corresponds to the "cat" field in the JSON event.
-  final String category;
+  final String? category;
 
   /// For a given long lasting event, denotes the phase of the event, such as
   /// "B" for "event began", and "E" for "event ended".
   ///
   /// Corresponds to the "ph" field in the JSON event.
-  final String phase;
+  final String? phase;
 
   /// ID of process that emitted the event.
   ///
   /// Corresponds to the "pid" field in the JSON event.
-  final int processId;
+  final int? processId;
 
   /// ID of thread that issues the event.
   ///
   /// Corresponds to the "tid" field in the JSON event.
-  final int threadId;
+  final int? threadId;
 
   /// The duration of the event.
   ///
@@ -82,7 +82,7 @@ class TimelineEvent {
   /// pair of begin/end events.
   ///
   /// Corresponds to the "dur" field in the JSON event.
-  final Duration duration;
+  final Duration? duration;
 
   /// The thread duration of the event.
   ///
@@ -90,32 +90,31 @@ class TimelineEvent {
   /// pair of begin/end events.
   ///
   /// Corresponds to the "tdur" field in the JSON event.
-  final Duration threadDuration;
+  final Duration? threadDuration;
 
   /// Time passed since tracing was enabled, in microseconds.
   ///
   /// Corresponds to the "ts" field in the JSON event.
-  final int timestampMicros;
+  final int? timestampMicros;
 
   /// Thread clock time, in microseconds.
   ///
   /// Corresponds to the "tts" field in the JSON event.
-  final int threadTimestampMicros;
+  final int? threadTimestampMicros;
 
   /// Arbitrary data attached to the event.
   ///
   /// Corresponds to the "args" field in the JSON event.
-  final Map<String, dynamic> arguments;
+  final Map<String, dynamic>? arguments;
 }
 
-List<TimelineEvent> _parseEvents(Map<String, dynamic> json) {
-  final List<dynamic> jsonEvents = json['traceEvents'] as List<dynamic>;
+List<TimelineEvent>? _parseEvents(Map<String, dynamic> json) {
+  final List<dynamic>? jsonEvents = json['traceEvents'] as List<dynamic>?;
 
   if (jsonEvents == null) {
     return null;
   }
 
-  // TODO(vegorov): use instance method version of castFrom when it is available.
   final List<TimelineEvent> timelineEvents =
       Iterable.castFrom<dynamic, Map<String, dynamic>>(jsonEvents)
           .map<TimelineEvent>(
@@ -123,8 +122,8 @@ List<TimelineEvent> _parseEvents(Map<String, dynamic> json) {
           .toList();
 
   timelineEvents.sort((TimelineEvent e1, TimelineEvent e2) {
-    final int ts1 = e1.timestampMicros;
-    final int ts2 = e2.timestampMicros;
+    final int? ts1 = e1.timestampMicros;
+    final int? ts2 = e2.timestampMicros;
     if (ts1 == null) {
       if (ts2 == null) {
         return 0;

packages/flutter_driver/lib/src/driver/timeline_summary.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import 'dart:convert' show json, JsonEncoder;
 import 'dart:math' as math;
 
@@ -197,7 +195,7 @@ class TimelineSummary {
   /// * [Timeline.fromJson], which explains detail about the timeline data.
   Future<void> writeTimelineToFile(
     String traceName, {
-    String destinationDirectory,
+    String? destinationDirectory,
     bool pretty = false,
   }) async {
     destinationDirectory ??= testOutputsDirectory;
@@ -209,7 +207,7 @@ class TimelineSummary {
   /// Writes [summaryJson] to a file.
   Future<void> writeSummaryToFile(
     String traceName, {
-    String destinationDirectory,
+    String? destinationDirectory,
     bool pretty = false,
   }) async {
     destinationDirectory ??= testOutputsDirectory;
@@ -225,13 +223,13 @@ class TimelineSummary {
   }
 
   List<TimelineEvent> _extractNamedEvents(String name) {
-    return _timeline.events
+    return _timeline.events!
       .where((TimelineEvent event) => event.name == name)
       .toList();
   }
 
   List<TimelineEvent> _extractEventsWithNames(Set<String> names) {
-    return _timeline.events
+    return _timeline.events!
       .where((TimelineEvent event) => names.contains(event.name))
       .toList();
   }
@@ -244,7 +242,7 @@ class TimelineSummary {
     final List<TimelineEvent> events = _extractNamedEvents(name);
 
     // Timeline does not guarantee that the first event is the "begin" event.
-    TimelineEvent begin;
+    TimelineEvent? begin;
     for (final TimelineEvent event in events) {
       if (event.phase == 'B') {
         begin = event;
@@ -273,7 +271,7 @@ class TimelineSummary {
     return _extractDurations(
       name,
       (TimelineEvent beginEvent, TimelineEvent endEvent) {
-        return Duration(microseconds: endEvent.timestampMicros - beginEvent.timestampMicros);
+        return Duration(microseconds: endEvent.timestampMicros! - beginEvent.timestampMicros!);
       },
     );
   }
@@ -282,7 +280,7 @@ class TimelineSummary {
     final List<Duration> result = _extractDurations(
       name,
       (TimelineEvent beginEvent, TimelineEvent endEvent) {
-        return Duration(microseconds: beginEvent.timestampMicros);
+        return Duration(microseconds: beginEvent.timestampMicros!);
       },
     );
 

packages/flutter_driver/lib/src/driver/web_driver.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import 'dart:convert';
 import 'dart:io';
 
@@ -53,7 +51,7 @@ class WebFlutterDriver extends FlutterDriver {
   /// DRIVER_SESSION_CAPABILITIES and ANDROID_CHROME_ON_EMULATOR for
   /// configurations.
   static Future<FlutterDriver> connectWeb(
-      {String hostUrl, Duration timeout}) async {
+      {String? hostUrl, Duration? timeout}) async {
     hostUrl ??= Platform.environment['VM_SERVICE_URL'];
     final Map<String, dynamic> settings = <String, dynamic>{
       'support-timeline-action': Platform.environment['SUPPORT_TIMELINE_ACTION'] == 'true',
@@ -64,7 +62,7 @@ class WebFlutterDriver extends FlutterDriver {
       'session-capabilities': Platform.environment['DRIVER_SESSION_CAPABILITIES'],
     };
     final FlutterWebConnection connection = await FlutterWebConnection.connect
-      (hostUrl, settings, timeout: timeout);
+      (hostUrl!, settings, timeout: timeout);
     return WebFlutterDriver.connectedTo(connection);
   }
 
@@ -90,7 +88,7 @@ class WebFlutterDriver extends FlutterDriver {
     final Map<String, String> serialized = command.serialize();
     try {
       final dynamic data = await _connection.sendCommand("window.\$flutterDriver('${jsonEncode(serialized)}')", command.timeout);
-      response = data != null ? json.decode(data as String) as Map<String, dynamic> : <String, dynamic>{};
+      response = data != null ? (json.decode(data as String) as Map<String, dynamic>?)! : <String, dynamic>{};
     } catch (error, stackTrace) {
       throw DriverError("Failed to respond to $command due to remote error\n : \$flutterDriver('${jsonEncode(serialized)}')",
           error,
@@ -132,7 +130,7 @@ class WebFlutterDriver extends FlutterDriver {
     final List<Map<String, dynamic>> events = <Map<String, dynamic>>[];
     for (final async_io.LogEntry entry in await _connection.logs.toList()) {
       if (_startTime.isBefore(entry.timestamp)) {
-        final Map<String, dynamic> data = jsonDecode(entry.message)['message'] as Map<String, dynamic>;
+        final Map<String, dynamic> data = jsonDecode(entry.message!)['message'] as Map<String, dynamic>;
         if (data['method'] == 'Tracing.dataCollected') {
           // 'ts' data collected from Chrome is in double format, conversion needed
           try {
@@ -142,7 +140,7 @@ class WebFlutterDriver extends FlutterDriver {
             // data is corrupted, skip
             continue;
           }
-          events.add(data['params'] as Map<String, dynamic>);
+          events.add(data['params']! as Map<String, dynamic>);
         }
       }
     }
@@ -203,7 +201,7 @@ class FlutterWebConnection {
   static Future<FlutterWebConnection> connect(
       String url,
       Map<String, dynamic> settings,
-      {Duration timeout}) async {
+      {Duration? timeout}) async {
     final String sessionId = settings['session-id'].toString();
     final Uri sessionUri = Uri.parse(settings['session-uri'].toString());
     final async_io.WebDriver driver = async_io.WebDriver(
@@ -226,7 +224,7 @@ class FlutterWebConnection {
   }
 
   /// Sends command via WebDriver to Flutter web application.
-  Future<dynamic> sendCommand(String script, Duration duration) async {
+  Future<dynamic> sendCommand(String script, Duration? duration) async {
     dynamic result;
     try {
       await _driver.execute(script, <void>[]);
@@ -265,7 +263,7 @@ class FlutterWebConnection {
 }
 
 /// Waits until extension is installed.
-Future<void> waitUntilExtensionInstalled(async_io.WebDriver driver, Duration timeout) async {
+Future<void> waitUntilExtensionInstalled(async_io.WebDriver driver, Duration? timeout) async {
   await waitFor<void>(() =>
       driver.execute(r'return typeof(window.$flutterDriver)', <String>[]),
       matcher: 'function',

packages/flutter_driver/pubspec.yaml

@@ -8,16 +8,16 @@ environment:
 
 dependencies:
   file: 6.0.0-nullsafety.4
-  meta: 1.3.0-nullsafety.6
-  path: 1.8.0-nullsafety.3
-  vm_service: 6.0.1-nullsafety.0
-  webdriver: 3.0.0-nullsafety.1
   flutter:
     sdk: flutter
   flutter_test:
     sdk: flutter
   fuchsia_remote_debug_protocol:
     sdk: flutter
+  path: 1.8.0-nullsafety.3
+  meta: 1.3.0-nullsafety.6
+  vm_service: 6.0.1-nullsafety.0
+  webdriver: 3.0.0-nullsafety.1
 
   archive: 3.0.0-nullsafety.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   async: 2.5.0-nullsafety.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
@@ -27,7 +27,6 @@ dependencies:
   clock: 1.1.0-nullsafety.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   collection: 1.15.0-nullsafety.5 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   crypto: 3.0.0-nullsafety.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  fake_async: 1.2.0-nullsafety.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   matcher: 0.12.10-nullsafety.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   platform: 3.0.0-nullsafety.4 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   process: 4.0.0-nullsafety.4 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
@@ -42,7 +41,7 @@ dependencies:
   vector_math: 2.1.0-nullsafety.5 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
 
 dev_dependencies:
-  quiver: 2.1.5
+  fake_async: 1.2.0-nullsafety.3
   test: 1.16.0-nullsafety.16
 
   _fe_analyzer_shared: 14.0.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
@@ -77,4 +76,4 @@ dev_dependencies:
   webkit_inspection_protocol: 0.7.4 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   yaml: 2.2.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
 
-# PUBSPEC CHECKSUM: 91b1
+# PUBSPEC CHECKSUM: 62c3

packages/flutter_driver/test/common.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import 'dart:io';
 
 import 'package:flutter_driver/src/common/error.dart';

packages/flutter_driver/test/src/real_tests/find_test.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import 'package:flutter_driver/driver_extension.dart';
 import 'package:flutter_driver/flutter_driver.dart';
 import 'package:flutter_driver/src/common/find.dart';

packages/flutter_driver/test/src/real_tests/io_extension_test.dart

@@ -2,15 +2,13 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import 'package:flutter_driver/src/extension/_extension_io.dart';
 
 import '../../common.dart';
 
 void main() {
   group('test io_extension',() {
-    Future<Map<String, dynamic>> Function(Map<String, String>) call;
+    late Future<Map<String, dynamic>> Function(Map<String, String>) call;
 
     setUp(() {
       call = (Map<String, String> args) async {

packages/flutter_driver/test/src/real_tests/request_data_test.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import 'package:flutter_driver/flutter_driver.dart';
 
 import '../../common.dart';

packages/flutter_driver/test/src/real_tests/timeline_summary_test.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import 'dart:convert' show json;
 
 import 'package:file/file.dart';
@@ -409,7 +407,7 @@ void main() {
 
     group('writeTimelineToFile', () {
 
-      Directory tempDir;
+      late Directory tempDir;
 
       setUp(() {
         useMemoryFileSystemForTesting();
@@ -480,7 +478,7 @@ void main() {
           final Timeline timeline = Timeline.fromJson(<String, dynamic>{
           'traceEvents': traceEvents,
           });
-          return SceneDisplayLagSummarizer(timeline.events);
+          return SceneDisplayLagSummarizer(timeline.events!);
       }
 
       test('average_vsyncs_missed', () async {
@@ -531,7 +529,7 @@ void main() {
           final Timeline timeline = Timeline.fromJson(<String, dynamic>{
             'traceEvents': traceEvents,
           });
-          return ProfilingSummarizer.fromEvents(timeline.events);
+          return ProfilingSummarizer.fromEvents(timeline.events!);
       }
 
       test('has_both_cpu_and_memory_usage', () async {

packages/flutter_driver/test/src/real_tests/timeline_test.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import 'package:flutter_driver/src/driver/timeline.dart';
 
 import '../../common.dart';
@@ -34,7 +32,7 @@ void main() {
 
       expect(timeline.events, hasLength(2));
 
-      final TimelineEvent e1 = timeline.events[1];
+      final TimelineEvent e1 = timeline.events![1];
       expect(e1.name, 'test event');
       expect(e1.category, 'test category');
       expect(e1.phase, 'B');
@@ -46,7 +44,7 @@ void main() {
       expect(e1.threadTimestampMicros, 567);
       expect(e1.arguments, <String, dynamic>{'arg1': true});
 
-      final TimelineEvent e2 = timeline.events[0];
+      final TimelineEvent e2 = timeline.events![0];
       expect(e2.name, isNull);
       expect(e2.category, isNull);
       expect(e2.phase, isNull);
@@ -74,10 +72,10 @@ void main() {
       });
 
       expect(timeline.events, hasLength(2));
-      expect(timeline.events[0].timestampMicros, equals(456));
-      expect(timeline.events[1].timestampMicros, equals(457));
-      expect(timeline.events[0].name, equals('test event 2'));
-      expect(timeline.events[1].name, equals('test event 1'));
+      expect(timeline.events![0].timestampMicros, equals(456));
+      expect(timeline.events![1].timestampMicros, equals(457));
+      expect(timeline.events![0].name, equals('test event 2'));
+      expect(timeline.events![1].name, equals('test event 1'));
     });
 
     test('sorts JSON nulls first', () {
@@ -103,14 +101,14 @@ void main() {
       });
 
       expect(timeline.events, hasLength(4));
-      expect(timeline.events[0].timestampMicros, isNull);
-      expect(timeline.events[1].timestampMicros, isNull);
-      expect(timeline.events[2].timestampMicros, equals(456));
-      expect(timeline.events[3].timestampMicros, equals(457));
-      expect(timeline.events[0].name, equals('test event 0'));
-      expect(timeline.events[1].name, equals('test event 3'));
-      expect(timeline.events[2].name, equals('test event 2'));
-      expect(timeline.events[3].name, equals('test event 1'));
+      expect(timeline.events![0].timestampMicros, isNull);
+      expect(timeline.events![1].timestampMicros, isNull);
+      expect(timeline.events![2].timestampMicros, equals(456));
+      expect(timeline.events![3].timestampMicros, equals(457));
+      expect(timeline.events![0].name, equals('test event 0'));
+      expect(timeline.events![1].name, equals('test event 3'));
+      expect(timeline.events![2].name, equals('test event 2'));
+      expect(timeline.events![3].name, equals('test event 1'));
     });
   });
 }

packages/flutter_driver/test/src/real_tests/wait_test.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import 'package:flutter_driver/src/common/wait.dart';
 
 import '../../common.dart';

packages/flutter_driver/test_driver/failure.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import 'package:flutter_driver/driver_extension.dart';
 
 void main() {

packages/flutter_driver/test_driver/failure_test.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import '../test/common.dart';
 
 void main() {

packages/flutter_driver/test_driver/success.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import 'package:flutter_driver/driver_extension.dart';
 
 void main() {

packages/flutter_driver/test_driver/success_test.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import '../test/common.dart';
 
 void main() {