[[ Bug 22688 ]] Don't set empty url on WKWebView

Ian Macphail · Ian Macphail · commit 4511b50e9471 · 2020-04-21T12:10:57.000+01:00
This patch fixes a bug where setting the url to empty would block subsequent
requests. Loading an empty url in the WKWebView browser would happen without
the expected 'decidePolicyForNavigationAction' message being sent to the
browser delegate as expected. To ensure the message is sent, we now load the
html text of a blank page into the browser instead.
diff --git a/libbrowser/src/libbrowser_wkwebview.mm b/libbrowser/src/libbrowser_wkwebview.mm
@@ -928,26 +928,35 @@ - (void)userContentController:(WKUserContentController *)userContentController d
 	if (!GetWebView(t_view))
 		return false;
 	
-//	__block NSURL *t_url;
 	NSURL *t_url;
-	t_url = [NSURL URLWithString: [NSString stringWithUTF8String: p_url]];
+	if (MCCStringIsEmpty(p_url))
+	{
+		// Sending an empty url to the webview will bypass the delegate's
+		// decidePolicyForNavigationAction method. We can prevent that by
+		// loading a blank page instead.
+		[m_delegate loadRequest:[MCWKWebViewLoadRequest requestWithUrl:nil htmlText:@"<html><body></body></html>" quiet:YES] inWebView:t_view];
+	}
+	else
+	{
+		t_url = [NSURL URLWithString: [NSString stringWithUTF8String: p_url]];
 
-	// reject file urls with empty path components
-	if (t_url.fileURL && t_url.path.length == 0)
-		return false;
+		// reject file urls with empty path components
+		if (t_url.fileURL && t_url.path.length == 0)
+			return false;
 
-	// check that we have permission to access file urls before proceeding
-	__block bool t_reachable = true;
-	if (t_url.fileURL)
-	{
-		MCBrowserRunBlockOnMainFiber(^{
-			t_reachable = [t_url checkResourceIsReachableAndReturnError:nil];
-		});
+		// check that we have permission to access file urls before proceeding
+		__block bool t_reachable = true;
+		if (t_url.fileURL)
+		{
+			MCBrowserRunBlockOnMainFiber(^{
+				t_reachable = [t_url checkResourceIsReachableAndReturnError:nil];
+			});
+		}
+		if (!t_reachable)
+			return false;
+		
+		[m_delegate loadRequest:[MCWKWebViewLoadRequest requestWithUrl:t_url htmlText:nil quiet:NO] inWebView:t_view];
 	}
-	if (!t_reachable)
-		return false;
-	
-	[m_delegate loadRequest:[MCWKWebViewLoadRequest requestWithUrl:t_url htmlText:nil quiet:NO] inWebView:t_view];
 	
 	/* UNCHECKED */ MCBrowserCStringAssignCopy(m_url, p_url);
 	MCBrowserCStringAssign(m_htmltext, nil);
