Merge branch 'implement_zoomEnabled_for_ios_and_android' into add_zoom_to_android_webview

* implement_zoomEnabled_for_ios_and_android:
  Adding test coverage for iOS

Author: NickalasB

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

@@ -13,13 +13,22 @@ @interface FLTWKNavigationDelegateTests : XCTestCase
 
 @property(strong, nonatomic) FlutterMethodChannel *mockMethodChannel;
 @property(strong, nonatomic) FLTWKNavigationDelegate *navigationDelegate;
+@property(strong, nonatomic) WKNavigation *navigation;
 
 @end
 
 @implementation FLTWKNavigationDelegateTests
 
+NSString *const expectedJavascript =
+  @"var meta = document.createElement('meta');"
+  @"meta.name = 'viewport';"
+  @"meta.content = 'width=device-width, initial-scale=1.0, maximum-scale=1.0,"
+  @"user-scalable=no';"
+  @"var head = document.getElementsByTagName('head')[0];head.appendChild(meta);";
+
 - (void)setUp {
   self.mockMethodChannel = OCMClassMock(FlutterMethodChannel.class);
+  self.navigation = OCMClassMock(WKNavigation.class);
   self.navigationDelegate =
       [[FLTWKNavigationDelegate alloc] initWithChannel:self.mockMethodChannel];
 }
@@ -38,4 +47,27 @@ - (void)testWebViewWebContentProcessDidTerminateCallsRecourseErrorChannel {
   }
 }
 
+- (void)testWebViewWebEvaluateJavaScriptSourceIsCorrectWhenShouldEnableZoomIsFalse {
+  WKWebView *webview = OCMClassMock(WKWebView.class);
+  NSURL *testUrl = [[NSURL alloc] initWithString:@"www.example.com"];
+  OCMStub([webview URL]).andReturn(testUrl);
+
+  self.navigationDelegate.shouldEnableZoom = false;
+  [self.navigationDelegate webView:webview didFinishNavigation:self.navigation];
+    
+  OCMVerify([webview evaluateJavaScript:expectedJavascript completionHandler:nil]);
+}
+
+- (void)testWebViewWebEvaluateJavaScriptShouldNotBeCalledWhenShouldEnableZoomIsTrue {
+  WKWebView *webview = OCMClassMock(WKWebView.class);
+  NSURL *testUrl = [[NSURL alloc] initWithString:@"www.example.com"];
+  OCMStub([webview URL]).andReturn(testUrl);
+
+  self.navigationDelegate.shouldEnableZoom = true;
+
+  OCMReject([webview evaluateJavaScript:expectedJavascript completionHandler:nil]);
+    
+  [self.navigationDelegate webView:webview didFinishNavigation:self.navigation];
+}
+
 @end