From 8538b4f546c9975f70de1e473eb4d8db8e52475e Mon Sep 17 00:00:00 2001
From: xubaolin <xubaolin@oppo.com>
Date: Tue, 13 Oct 2020 00:37:03 +0800
Subject: [PATCH] Fix TextField bug when the formatter repeatedly format
 (#67892)

---
 .../lib/src/widgets/editable_text.dart        | 11 ++-
 .../test/widgets/editable_text_test.dart      | 78 +++++++++++++++++++
 2 files changed, 87 insertions(+), 2 deletions(-)

diff --git a/packages/flutter/lib/src/widgets/editable_text.dart b/packages/flutter/lib/src/widgets/editable_text.dart
index 5bb9612f152..97a8dd13006 100644
--- a/packages/flutter/lib/src/widgets/editable_text.dart
+++ b/packages/flutter/lib/src/widgets/editable_text.dart
@@ -2212,8 +2212,15 @@ class EditableTextState extends State<EditableText> with AutomaticKeepAliveClien
       _lastFormattedValue = value;
     }
 
-    // Setting _value here ensures the selection and composing region info is passed.
-    _value = value;
+    if (value == _value) {
+      // If the value was modified by the formatter, the remote should be notified to keep in sync,
+      // if not modified, it will short-circuit.
+      _updateRemoteEditingValueIfNeeded();
+    } else {
+      // Setting _value here ensures the selection and composing region info is passed.
+      _value = value;
+    }
+
     // Use the last formatted value when an identical repeat pass is detected.
     if (isRepeat && textChanged && _lastFormattedValue != null) {
       _value = _lastFormattedValue!;
diff --git a/packages/flutter/test/widgets/editable_text_test.dart b/packages/flutter/test/widgets/editable_text_test.dart
index 2872d7a39b4..01f8942729d 100644
--- a/packages/flutter/test/widgets/editable_text_test.dart
+++ b/packages/flutter/test/widgets/editable_text_test.dart
@@ -4998,6 +4998,84 @@ void main() {
     );
   });
 
+  testWidgets('Send text input state to engine when the input formatter rejects user input', (WidgetTester tester) async {
+    // Regression test for https://github.com/flutter/flutter/issues/67828
+    final List<MethodCall> log = <MethodCall>[];
+    SystemChannels.textInput.setMockMethodCallHandler((MethodCall methodCall) async {
+      log.add(methodCall);
+    });
+    final TextInputFormatter formatter = TextInputFormatter.withFunction((TextEditingValue oldValue, TextEditingValue newValue) {
+      return const TextEditingValue(text: 'Flutter is the best!');
+    });
+    final TextEditingController controller = TextEditingController();
+
+    final FocusNode focusNode = FocusNode(debugLabel: 'EditableText Focus Node');
+    Widget builder() {
+      return StatefulBuilder(
+        builder: (BuildContext context, StateSetter setter) {
+          return MaterialApp(
+            home: MediaQuery(
+              data: const MediaQueryData(devicePixelRatio: 1.0),
+              child: Directionality(
+                textDirection: TextDirection.ltr,
+                child: Center(
+                  child: Material(
+                    child: EditableText(
+                      controller: controller,
+                      focusNode: focusNode,
+                      style: textStyle,
+                      cursorColor: Colors.red,
+                      backgroundCursorColor: Colors.red,
+                      keyboardType: TextInputType.multiline,
+                      inputFormatters: <TextInputFormatter>[
+                        formatter,
+                      ],
+                      onChanged: (String value) { },
+                    ),
+                  ),
+                ),
+              ),
+            ),
+          );
+        },
+      );
+    }
+
+    await tester.pumpWidget(builder());
+    await tester.tap(find.byType(EditableText));
+    await tester.showKeyboard(find.byType(EditableText));
+    await tester.pump();
+
+    log.clear();
+
+    final EditableTextState state = tester.firstState(find.byType(EditableText));
+
+    // setEditingState is called when remote value modified by the formatter.
+    state.updateEditingValue(const TextEditingValue(
+      text: 'I will be modified by the formatter.',
+    ));
+    expect(log.length, 1);
+    expect(log, contains(matchesMethodCall(
+      'TextInput.setEditingState',
+      args: allOf(
+        containsPair('text', 'Flutter is the best!'),
+      ),
+    )));
+
+    log.clear();
+
+    state.updateEditingValue(const TextEditingValue(
+      text: 'I will be modified by the formatter.',
+    ));
+    expect(log.length, 1);
+    expect(log, contains(matchesMethodCall(
+      'TextInput.setEditingState',
+      args: allOf(
+        containsPair('text', 'Flutter is the best!'),
+      ),
+    )));
+  });
+
   testWidgets('autofocus:true on first frame does not throw', (WidgetTester tester) async {
     final TextEditingController controller = TextEditingController(text: testText);
     controller.selection = const TextSelection(