Clarify hot restart behavior on the web (#42931)

packages/flutter_tools/lib/src/build_runner/resident_web_runner.dart

@@ -120,8 +120,8 @@ class ResidentWebRunner extends ResidentRunner {
       return printHelpDetails();
     }
     const String fire = '🔥';
-    const String rawMessage =
-        '  To hot restart (and rebuild state), press "r" or "R".';
+    const String rawMessage = '  To hot restart changes while running, press "r". '
+      'To hot restart (and refresh the browser), press "R".';
     final String message = terminal.color(
       fire + terminal.bolden(rawMessage),
       TerminalColor.red,
@@ -297,16 +297,21 @@ class ResidentWebRunner extends ResidentRunner {
       final Duration recompileDuration = timer.elapsed;
       flutterUsage.sendTiming('hot', 'web-recompile', recompileDuration);
       try {
-        final vmservice.Response reloadResponse = await _vmService.callServiceExtension('hotRestart');
-        printStatus('Restarted application in ${getElapsedAsMilliseconds(timer.elapsed)}.');
+        final vmservice.Response reloadResponse = fullRestart
+           ? await _vmService.callServiceExtension('fullReload')
+           : await _vmService.callServiceExtension('hotRestart');
+        final String verb = fullRestart ? 'Restarted' : 'Reloaded';
+        printStatus('$verb application in ${getElapsedAsMilliseconds(timer.elapsed)}.');
 
         // Send timing analytics for full restart and for refresh.
         final bool wasSuccessful = reloadResponse.type == 'Success';
         if (!wasSuccessful) {
           return OperationResult(1, reloadResponse.toString());
         }
+        if (!fullRestart) {
           flutterUsage.sendTiming('hot', 'web-restart', timer.elapsed);
           flutterUsage.sendTiming('hot', 'web-refresh', timer.elapsed - recompileDuration);
+        }
         return OperationResult.ok;
       } on vmservice.RPCError {
         return OperationResult(1, 'Page requires refresh.');

packages/flutter_tools/test/general.shard/resident_web_runner_test.dart

@@ -176,6 +176,7 @@ void main() {
 
   test('Can hot reload after attaching', () => testbed.run(() async {
     _setupMocks();
+    final BufferLogger bufferLogger = logger;
     final Completer<DebugConnectionInfo> connectionInfoCompleter = Completer<DebugConnectionInfo>();
     unawaited(residentWebRunner.run(
       connectionInfoCompleter: connectionInfoCompleter,
@@ -189,6 +190,7 @@ void main() {
     });
     final OperationResult result = await residentWebRunner.restart(fullRestart: false);
 
+    expect(bufferLogger.statusText, contains('Reloaded application in'));
     expect(result.code, 0);
 	  // ensure that analytics are sent.
     verify(Usage.instance.sendEvent('hot', 'restart', parameters: <String, String>{
@@ -206,6 +208,7 @@ void main() {
 
   test('Can hot restart after attaching', () => testbed.run(() async {
     _setupMocks();
+    final BufferLogger bufferLogger = logger;
     final Completer<DebugConnectionInfo> connectionInfoCompleter = Completer<DebugConnectionInfo>();
     unawaited(residentWebRunner.run(
       connectionInfoCompleter: connectionInfoCompleter,
@@ -214,11 +217,12 @@ void main() {
     when(mockWebFs.recompile()).thenAnswer((Invocation invocation) async {
       return true;
     });
-    when(mockVmService.callServiceExtension('hotRestart')).thenAnswer((Invocation _) async {
+    when(mockVmService.callServiceExtension('fullReload')).thenAnswer((Invocation _) async {
       return Response.parse(<String, Object>{'type': 'Success'});
     });
     final OperationResult result = await residentWebRunner.restart(fullRestart: true);
 
+    expect(bufferLogger.statusText, contains('Restarted application in'));
     expect(result.code, 0);
 	  // ensure that analytics are sent.
     verify(Usage.instance.sendEvent('hot', 'restart', parameters: <String, String>{
@@ -227,8 +231,8 @@ void main() {
       'cd29': 'false',
       'cd30': 'true',
     })).called(1);
-    verify(Usage.instance.sendTiming('hot', 'web-restart', any)).called(1);
-    verify(Usage.instance.sendTiming('hot', 'web-refresh', any)).called(1);
+    verifyNever(Usage.instance.sendTiming('hot', 'web-restart', any));
+    verifyNever(Usage.instance.sendTiming('hot', 'web-refresh', any));
     verify(Usage.instance.sendTiming('hot', 'web-recompile', any)).called(1);
   }, overrides: <Type, Generator>{
     Usage: () => MockFlutterUsage(),
@@ -255,7 +259,7 @@ void main() {
     Usage: () => MockFlutterUsage(),
   }));
 
-  test('Fails on vmservice response error', () => testbed.run(() async {
+  test('Fails on vmservice response error for hot restart', () => testbed.run(() async {
     _setupMocks();
     final Completer<DebugConnectionInfo> connectionInfoCompleter = Completer<DebugConnectionInfo>();
     unawaited(residentWebRunner.run(
@@ -265,7 +269,7 @@ void main() {
     when(mockWebFs.recompile()).thenAnswer((Invocation _) async {
       return true;
     });
-    when(mockVmService.callServiceExtension('hotRestart')).thenAnswer((Invocation _) async {
+    when(mockVmService.callServiceExtension('fullReload')).thenAnswer((Invocation _) async {
       return Response.parse(<String, Object>{'type': 'Failed'});
     });
     final OperationResult result = await residentWebRunner.restart(fullRestart: true);
@@ -279,6 +283,30 @@ void main() {
     Usage: () => MockFlutterUsage(),
   }));
 
+  test('Fails on vmservice response error for hot reload', () => testbed.run(() async {
+    _setupMocks();
+    final Completer<DebugConnectionInfo> connectionInfoCompleter = Completer<DebugConnectionInfo>();
+    unawaited(residentWebRunner.run(
+      connectionInfoCompleter: connectionInfoCompleter,
+    ));
+    await connectionInfoCompleter.future;
+    when(mockWebFs.recompile()).thenAnswer((Invocation _) async {
+      return true;
+    });
+    when(mockVmService.callServiceExtension('hotRestart')).thenAnswer((Invocation _) async {
+      return Response.parse(<String, Object>{'type': 'Failed'});
+    });
+    final OperationResult result = await residentWebRunner.restart(fullRestart: false);
+
+    expect(result.code, 1);
+    expect(result.message, contains('Failed'));
+    verifyNever(Usage.instance.sendTiming('hot', 'web-restart', any));
+    verifyNever(Usage.instance.sendTiming('hot', 'web-refresh', any));
+    verify(Usage.instance.sendTiming('hot', 'web-recompile', any)).called(1);
+  }, overrides: <Type, Generator>{
+    Usage: () => MockFlutterUsage(),
+  }));
+
   test('Fails on vmservice RpcError', () => testbed.run(() async {
     _setupMocks();
     final Completer<DebugConnectionInfo> connectionInfoCompleter = Completer<DebugConnectionInfo>();
@@ -290,7 +318,7 @@ void main() {
       return true;
     });
     when(mockVmService.callServiceExtension('hotRestart')).thenThrow(RPCError('', 2, '123'));
-    final OperationResult result = await residentWebRunner.restart(fullRestart: true);
+    final OperationResult result = await residentWebRunner.restart(fullRestart: false);
 
     expect(result.code, 1);
     expect(result.message, contains('Page requires refresh'));