rest of tests

packages/webview_flutter/webview_flutter_wkwebview/example/ios/RunnerTests/FWFWebViewHostApiTests.m

@@ -312,38 +312,29 @@ - (void)testSetAllowsBackForwardNavigationGestures {
   XCTAssertNil(error);
 }
 
-//- (void)testevaluateJavaScript {
-//  FWFWebView *mockWebView = OCMClassMock([FWFWebView class]);
-//  OCMStub([mockWebView evaluateJavaScript
-//
-//  :aValue
-//
-//
-//  ]).andReturn(aValue);
-//
-//  FWFInstanceManager *instanceManager = [[FWFInstanceManager alloc] init];
-//  [instanceManager addInstance:mockWebView withIdentifier:0];
-//
-//  FWFWebViewHostApiImpl *hostApi =
-//      [[FWFWebViewHostApiImpl alloc] initWithInstanceManager:instanceManager];
-//
-//  FlutterError *error;
-//  XCTAssertEqualObjects([hostApi evaluateJavaScriptForWebViewWithIdentifier:@0
-//
-//                                  javaScriptString:aValue
-//
-//                                                                   error:&error], @YES);
-//  [hostApi evaluateJavaScriptForWebViewWithIdentifier:@0
-//
-//                                javaScriptString:aValue
-//
-//                                             error:&error];
-//  OCMVerify([mockWebView evaluateJavaScript
-//
-//    :aValue
-//
-//
-//  ]);
-//  XCTAssertNil(error);
-//}
+- (void)testEvaluateJavaScript {
+  FWFWebView *mockWebView = OCMClassMock([FWFWebView class]);
+
+  OCMStub([mockWebView
+      evaluateJavaScript:@"runJavaScript"
+       completionHandler:([OCMArg invokeBlockWithArgs:@"result", [NSNull null], nil])]);
+
+  FWFInstanceManager *instanceManager = [[FWFInstanceManager alloc] init];
+  [instanceManager addInstance:mockWebView withIdentifier:0];
+
+  FWFWebViewHostApiImpl *hostApi =
+      [[FWFWebViewHostApiImpl alloc] initWithInstanceManager:instanceManager];
+
+  NSString __block *returnValue;
+  FlutterError __block *returnError;
+  [hostApi evaluateJavaScriptForWebViewWithIdentifier:@0
+                                     javaScriptString:@"runJavaScript"
+                                           completion:^(id result, FlutterError *error) {
+                                             returnValue = result;
+                                             returnError = error;
+                                           }];
+
+  XCTAssertEqualObjects(returnValue, @"result");
+  XCTAssertNil(returnError);
+}
 @end

packages/webview_flutter/webview_flutter_wkwebview/ios/Classes/FWFWebViewHostApi.h

@@ -10,6 +10,11 @@
 
 NS_ASSUME_NONNULL_BEGIN
 
+/**
+ * A set of Flutter and Dart assets used by a `FlutterEngine` to initialize execution.
+ *
+ * Default implementation delegates methods to FlutterDartProject.
+ */
 @interface FWFAssetManager : NSObject
 - (NSString *)lookupKeyForAsset:(NSString *)asset;
 @end

packages/webview_flutter/webview_flutter_wkwebview/ios/Classes/FWFWebViewHostApi.m

@@ -14,7 +14,7 @@ - (NSString *)lookupKeyForAsset:(NSString *)asset {
 @implementation FWFWebView
 - (void)setFrame:(CGRect)frame {
   [super setFrame:frame];
-  // Prevents the contentInsets to be adjusted by iOS and gives control to Flutter.
+  // Prevents the contentInsets from being adjusted by iOS and gives control to Flutter.
   self.scrollView.contentInset = UIEdgeInsetsZero;
   if (@available(iOS 11, *)) {
     // Above iOS 11, adjust contentInset to compensate the adjustedContentInset so the sum will
@@ -143,14 +143,10 @@ - (void)evaluateJavaScriptForWebViewWithIdentifier:(nonnull NSNumber *)instanceI
              returnValue = result;
            } else {
              NSString *className = NSStringFromClass([result class]);
-             NSString *message = [NSString
-                 stringWithFormat:
-                     @"Return type not supported: %@. Description of value was added to details.",
-                     className];
-             flutterError =
-                 [FlutterError errorWithCode:@"FWFEvaluateJavaScriptResultNotSupportedError"
-                                     message:message
-                                     details:[result description]];
+             NSLog(@"Return type of evaluateJavaScript is not directly supported: %@. Returned "
+                   @"description of value.",
+                   className);
+             returnValue = [result description];
            }
          } else {
            flutterError = [FlutterError errorWithCode:@"FWFEvaluateJavaScriptError"