macOS fluttertextinputplugin drops selector called if no client

Author: chunhtai

shell/platform/darwin/macos/framework/Source/FlutterTextInputPlugin.mm

@@ -438,7 +438,6 @@ - (void)handleMethodCall:(FlutterMethodCall*)call result:(FlutterResult)result {
       _activeModel->EndComposing();
     }
     [_textInputContext discardMarkedText];
-
     _clientID = nil;
     _inputAction = nil;
     _enableDeltaModel = NO;
@@ -777,6 +776,10 @@ - (void)doCommandBySelector:(SEL)selector {
     void (*func)(id, SEL, id) = reinterpret_cast<void (*)(id, SEL, id)>(imp);
     func(self, selector, nil);
   }
+  if (self.clientID == nil) {
+    // The macOS may still call selector even if it is no longer a first responder.
+    return;
+  }
 
   if (selector == @selector(insertNewline:)) {
     // Already handled through text insertion (multiline) or action.

shell/platform/darwin/macos/framework/Source/FlutterTextInputPluginTest.mm

@@ -1801,6 +1801,49 @@ - (bool)testSelectorsAreForwardedToFramework {
   return true;
 }
 
+- (bool)testSelectorsNotForwardedToFrameworkIfNoClient {
+  id engineMock = flutter::testing::CreateMockFlutterEngine(@"");
+  id binaryMessengerMock = OCMProtocolMock(@protocol(FlutterBinaryMessenger));
+  OCMStub(  // NOLINT(google-objc-avoid-throwing-exception)
+      [engineMock binaryMessenger])
+      .andReturn(binaryMessengerMock);
+  // Make sure the selectors are not forwarded to the framework.
+  OCMReject([binaryMessengerMock sendOnChannel:@"flutter/textinput" message:[OCMArg any]]);
+  FlutterViewController* viewController = [[FlutterViewController alloc] initWithEngine:engineMock
+                                                                                nibName:@""
+                                                                                 bundle:nil];
+
+  FlutterTextInputPlugin* plugin =
+      [[FlutterTextInputPlugin alloc] initWithViewController:viewController];
+
+  // Can't run CFRunLoop in default mode because it causes crashes from scheduled
+  // sources from other tests.
+  NSString* runLoopMode = @"FlutterTestRunLoopMode";
+  plugin.customRunLoopMode = runLoopMode;
+
+  // Ensure both selectors are grouped in one platform channel call.
+  [plugin doCommandBySelector:@selector(moveUp:)];
+  [plugin doCommandBySelector:@selector(moveRightAndModifySelection:)];
+
+  // Clear the client before the CFRunLoop is run.
+  [plugin handleMethodCall:[FlutterMethodCall methodCallWithMethodName:@"TextInput.clearClient"
+                                                             arguments:@[]]
+                    result:^(id){
+                    }];
+
+  __block bool done = false;
+  CFRunLoopPerformBlock(CFRunLoopGetMain(), (__bridge CFStringRef)runLoopMode, ^{
+    done = true;
+  });
+
+  while (!done) {
+    // Each invocation will handle one source.
+    CFRunLoopRunInMode((__bridge CFStringRef)runLoopMode, 0, true);
+  }
+  // At this point the selectors should be dropped; otherwise, OCMReject will throw.
+  return true;
+}
+
 @end
 
 namespace flutter::testing {
@@ -1886,7 +1929,7 @@ - (bool)testSelectorsAreForwardedToFramework {
   ASSERT_TRUE([[FlutterInputPluginTestObjc alloc] testComposingWithDelta]);
 }
 
-TEST(FlutterTextInputPluginTest, testComposingWithDeltasWhenSelectionIsActive) {
+TEST(FlutterTextInputPluginTest, TestComposingWithDeltasWhenSelectionIsActive) {
   ASSERT_TRUE([[FlutterInputPluginTestObjc alloc] testComposingWithDeltasWhenSelectionIsActive]);
 }
 
@@ -1910,6 +1953,10 @@ - (bool)testSelectorsAreForwardedToFramework {
   ASSERT_TRUE([[FlutterInputPluginTestObjc alloc] testSelectorsAreForwardedToFramework]);
 }
 
+TEST(FlutterTextInputPluginTest, TestSelectorsNotForwardedToFrameworkIfNoClient) {
+  ASSERT_TRUE([[FlutterInputPluginTestObjc alloc] testSelectorsNotForwardedToFrameworkIfNoClient]);
+}
+
 TEST(FlutterTextInputPluginTest, TestInsertNewLine) {
   ASSERT_TRUE([[FlutterInputPluginTestObjc alloc] testInsertNewLine]);
 }