Fix requestExistingInputState response (#47472)

packages/flutter/lib/src/services/text_input.dart

@@ -753,6 +753,9 @@ abstract class TextInputClient {
   /// Updates the floating cursor position and state.
   void updateFloatingCursor(RawFloatingCursorPoint point);
 
+  /// The current state of the [TextEditingValue] held by this client.
+  TextEditingValue get currentTextEditingValue;
+
   /// Platform notified framework of closed connection.
   ///
   /// [TextInputClient] should cleanup its connection and finalize editing.
@@ -1036,7 +1039,6 @@ class TextInput {
 
   TextInputConnection _currentConnection;
   TextInputConfiguration _currentConfiguration;
-  TextEditingValue _currentTextEditingValue;
 
   Future<dynamic> _handleTextInputInvocation(MethodCall methodCall) async {
     if (_currentConnection == null)
@@ -1048,9 +1050,9 @@ class TextInput {
     if (method == 'TextInputClient.requestExistingInputState') {
       assert(_currentConnection._client != null);
       _attach(_currentConnection, _currentConfiguration);
-      // This will be null if we've never had a call to [_setEditingState].
-      if (_currentTextEditingValue != null) {
-        _setEditingState(_currentTextEditingValue);
+      final TextEditingValue editingValue = _currentConnection._client.currentTextEditingValue;
+      if (editingValue != null) {
+        _setEditingState(editingValue);
       }
       return;
     }
@@ -1110,7 +1112,6 @@ class TextInput {
       'TextInput.setEditingState',
       value.toJSON(),
     );
-    _currentTextEditingValue = value;
   }
 
   void _show() {

packages/flutter/lib/src/widgets/editable_text.dart

@@ -1202,6 +1202,9 @@ class EditableTextState extends State<EditableText> with AutomaticKeepAliveClien
 
   TextEditingValue _lastKnownRemoteTextEditingValue;
 
+  @override
+  TextEditingValue get currentTextEditingValue => _value;
+
   @override
   void updateEditingValue(TextEditingValue value) {
     // Since we still have to support keyboard select, this is the best place

packages/flutter/test/services/text_input_test.dart

@@ -13,12 +13,10 @@ void main() {
 
   group('TextInput message channels', () {
     FakeTextChannel fakeTextChannel;
-    FakeTextInputClient client;
 
     setUp(() {
       fakeTextChannel = FakeTextChannel((MethodCall call) async {});
       TextInput.setChannel(fakeTextChannel);
-      client = FakeTextInputClient();
     });
 
     tearDown(() {
@@ -27,6 +25,7 @@ void main() {
     });
 
     test('text input client handler responds to reattach with setClient', () async {
+      final FakeTextInputClient client = FakeTextInputClient(const TextEditingValue(text: 'test1'));
       TextInput.attach(client, client.configuration);
       fakeTextChannel.validateOutgoingMethodCalls(<MethodCall>[
         MethodCall('TextInput.setClient', <dynamic>[1, client.configuration.toJson()]),
@@ -34,39 +33,31 @@ void main() {
 
       fakeTextChannel.incoming(const MethodCall('TextInputClient.requestExistingInputState', null));
 
-      expect(fakeTextChannel.outgoingCalls.length, 2);
+      expect(fakeTextChannel.outgoingCalls.length, 3);
       fakeTextChannel.validateOutgoingMethodCalls(<MethodCall>[
         // From original attach
         MethodCall('TextInput.setClient', <dynamic>[1, client.configuration.toJson()]),
         // From requestExistingInputState
         MethodCall('TextInput.setClient', <dynamic>[1, client.configuration.toJson()]),
+        MethodCall('TextInput.setEditingState', client.currentTextEditingValue.toJSON()),
       ]);
     });
 
-    test('text input client handler responds to reattach with setClient and text state', () async {
-      final TextInputConnection connection = TextInput.attach(client, client.configuration);
-      fakeTextChannel.validateOutgoingMethodCalls(<MethodCall>[
-        MethodCall('TextInput.setClient', <dynamic>[1, client.configuration.toJson()]),
-      ]);
-
-      const TextEditingValue editingState = TextEditingValue(text: 'foo');
-      connection.setEditingState(editingState);
+    test('text input client handler responds to reattach with setClient (null TextEditingValue)', () async {
+      final FakeTextInputClient client = FakeTextInputClient(null);
+      TextInput.attach(client, client.configuration);
       fakeTextChannel.validateOutgoingMethodCalls(<MethodCall>[
         MethodCall('TextInput.setClient', <dynamic>[1, client.configuration.toJson()]),
-        MethodCall('TextInput.setEditingState', editingState.toJSON()),
       ]);
 
       fakeTextChannel.incoming(const MethodCall('TextInputClient.requestExistingInputState', null));
 
-      expect(fakeTextChannel.outgoingCalls.length, 4);
+      expect(fakeTextChannel.outgoingCalls.length, 2);
       fakeTextChannel.validateOutgoingMethodCalls(<MethodCall>[
-        // attach
+        // From original attach
         MethodCall('TextInput.setClient', <dynamic>[1, client.configuration.toJson()]),
-        // set editing state 1
-        MethodCall('TextInput.setEditingState', editingState.toJSON()),
-        // both from requestExistingInputState
+        // From requestExistingInputState
         MethodCall('TextInput.setClient', <dynamic>[1, client.configuration.toJson()]),
-        MethodCall('TextInput.setEditingState', editingState.toJSON()),
       ]);
     });
   });
@@ -153,7 +144,7 @@ void main() {
 
     test('TextInputClient onConnectionClosed method is called', () async {
       // Assemble a TextInputConnection so we can verify its change in state.
-      final FakeTextInputClient client = FakeTextInputClient();
+      final FakeTextInputClient client = FakeTextInputClient(const TextEditingValue(text: 'test3'));
       const TextInputConfiguration configuration = TextInputConfiguration();
       TextInput.attach(client, configuration);
 
@@ -176,8 +167,13 @@ void main() {
 }
 
 class FakeTextInputClient implements TextInputClient {
+  FakeTextInputClient(this.currentTextEditingValue);
+
   String latestMethodCall = '';
 
+  @override
+  TextEditingValue currentTextEditingValue;
+
   @override
   void performAction(TextInputAction action) {
     latestMethodCall = 'performAction';
@@ -231,7 +227,6 @@ class FakeTextChannel implements MethodChannel {
   @override
   String get name => 'flutter/textinput';
 
-
   @override
   void setMethodCallHandler(Future<void> Function(MethodCall call) handler) {
     incoming = handler;
@@ -252,7 +247,7 @@ class FakeTextChannel implements MethodChannel {
       if (outgoingString != expectedString) {
         print(
           'Index $i did not match:\n'
-          '  actual: ${outgoingCalls[i]}'
+          '  actual:   ${outgoingCalls[i]}\n'
           '  expected: ${calls[i]}');
         hasError = true;
       }