Started asserting the FlutterEngine is running before communicating o…

…ver channels. (flutter#12469) Started asserting the FlutterEngine is running before communicating over channels. This changes a null pointer exception to an NSException that will provide some meaningful data to clients incorrectly using the engine in an add-to-app situations.
elancom · Sep 27, 2019 · 3c271bb · 3c271bb
1 parent 57f35d2
commit 3c271bb
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Showing 3 changed files with 37 additions and 6 deletions.
diff --git a/shell/platform/darwin/ios/framework/Source/FlutterEngine.mm b/shell/platform/darwin/ios/framework/Source/FlutterEngine.mm
@@ -543,7 +543,9 @@ - (void)sendOnChannel:(NSString*)channel message:(NSData*)message {
 - (void)sendOnChannel:(NSString*)channel
               message:(NSData*)message
           binaryReply:(FlutterBinaryReply)callback {
-  NSAssert(channel, @"The channel must not be null");
+  NSParameterAssert(channel);
+  NSAssert(_shell && _shell->IsSetup(),
+           @"Sending a message before the FlutterEngine has been run.");
   fml::RefPtr<flutter::PlatformMessageResponseDarwin> response =
       (callback == nil) ? nullptr
                         : fml::MakeRefCounted<flutter::PlatformMessageResponseDarwin>(
@@ -561,8 +563,9 @@ - (void)sendOnChannel:(NSString*)channel
 
 - (void)setMessageHandlerOnChannel:(NSString*)channel
               binaryMessageHandler:(FlutterBinaryMessageHandler)handler {
-  NSAssert(channel, @"The channel must not be null");
-  FML_DCHECK(_shell && _shell->IsSetup());
+  NSParameterAssert(channel);
+  NSAssert(_shell && _shell->IsSetup(),
+           @"Setting a message handler before the FlutterEngine has been run.");
   self.iosPlatformView->GetPlatformMessageRouter().SetMessageHandler(channel.UTF8String, handler);
 }
 

diff --git a/shell/platform/darwin/ios/framework/Source/FlutterEngineTest.mm b/shell/platform/darwin/ios/framework/Source/FlutterEngineTest.mm
@@ -6,6 +6,14 @@
 #import <XCTest/XCTest.h>
 #import "flutter/shell/platform/darwin/ios/framework/Headers/FlutterEngine.h"
 
+#ifndef __has_feature
+#define __has_feature(x) 0 /* for non-clang compilers */
+#endif
+
+#if !__has_feature(objc_arc)
+#error ARC must be enabled!
+#endif
+
 @interface FlutteEngineTest : XCTestCase
 @end
 
@@ -19,9 +27,29 @@ - (void)tearDown {
 
 - (void)testCreate {
   id project = OCMClassMock([FlutterDartProject class]);
-  FlutterEngine* engine = [[[FlutterEngine alloc] initWithName:@"foobar"
-                                                       project:project] autorelease];
+  FlutterEngine* engine = [[FlutterEngine alloc] initWithName:@"foobar" project:project];
+  XCTAssertNotNil(engine);
+}
+
+- (void)testSendMessageBeforeRun {
+  id project = OCMClassMock([FlutterDartProject class]);
+  FlutterEngine* engine = [[FlutterEngine alloc] initWithName:@"foobar" project:project];
   XCTAssertNotNil(engine);
+  XCTAssertThrows([engine.binaryMessenger
+      sendOnChannel:@"foo"
+            message:[@"bar" dataUsingEncoding:NSUTF8StringEncoding]
+        binaryReply:nil]);
+}
+
+- (void)testSetMessageHandlerBeforeRun {
+  id project = OCMClassMock([FlutterDartProject class]);
+  FlutterEngine* engine = [[FlutterEngine alloc] initWithName:@"foobar" project:project];
+  XCTAssertNotNil(engine);
+  XCTAssertThrows([engine.binaryMessenger
+      setMessageHandlerOnChannel:@"foo"
+            binaryMessageHandler:^(NSData* _Nullable message, FlutterBinaryReply _Nonnull reply){
+
+            }]);
 }
 
 @end
diff --git a/testing/ios/IosUnitTests/IosUnitTests.xcodeproj/project.pbxproj b/testing/ios/IosUnitTests/IosUnitTests.xcodeproj/project.pbxproj
@@ -17,7 +17,7 @@
 		0D6AB6BE22BB05E200EEE540 /* Assets.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = 0D6AB6BD22BB05E200EEE540 /* Assets.xcassets */; };
 		0D6AB6C122BB05E200EEE540 /* LaunchScreen.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = 0D6AB6BF22BB05E200EEE540 /* LaunchScreen.storyboard */; };
 		0D6AB6C422BB05E200EEE540 /* main.m in Sources */ = {isa = PBXBuildFile; fileRef = 0D6AB6C322BB05E200EEE540 /* main.m */; };
-		0D6AB6EB22BB40E700EEE540 /* FlutterEngineTest.mm in Sources */ = {isa = PBXBuildFile; fileRef = 0D6AB6E722BB40CF00EEE540 /* FlutterEngineTest.mm */; };
+		0D6AB6EB22BB40E700EEE540 /* FlutterEngineTest.mm in Sources */ = {isa = PBXBuildFile; fileRef = 0D6AB6E722BB40CF00EEE540 /* FlutterEngineTest.mm */; settings = {COMPILER_FLAGS = "-fobjc-arc"; }; };
 		0D6AB72C22BC339F00EEE540 /* libOCMock.a in Frameworks */ = {isa = PBXBuildFile; fileRef = 0D6AB72522BC336100EEE540 /* libOCMock.a */; };
 		0D6AB73F22BD8F0200EEE540 /* FlutterEngineConfig.xcconfig in Resources */ = {isa = PBXBuildFile; fileRef = 0D6AB73E22BD8F0200EEE540 /* FlutterEngineConfig.xcconfig */; };
 /* End PBXBuildFile section */