fix: make sure invalid URL loads promises are fulfilled.

lib/browser/api/web-contents.ts

@@ -352,12 +352,12 @@
       removeListeners();
       resolve();
     };
     let error: LoadError | undefined;
     const rejectAndCleanup = ({ errorCode, errorDescription, url }: LoadError) => {
       const err = new Error(`${errorDescription} (${errorCode}) loading '${typeof url === 'string' ? url.substr(0, 2048) : url}'`);
       Object.assign(err, { errno: errorCode, code: errorDescription, url });
       removeListeners();
       reject(err);
     };
     const finishListener = () => {
       if (error) {
@@ -366,11 +366,6 @@
         resolveAndCleanup();
       }
     };
-    const failListener = (event: Electron.Event, errorCode: number, errorDescription: string, validatedURL: string, isMainFrame: boolean) => {
-      if (!error && isMainFrame) {
-        error = { errorCode, errorDescription, url: validatedURL };
-      }
-    };
 
     let navigationStarted = false;
     let browserInitiatedInPageNavigation = false;
@@ -392,6 +387,14 @@
         navigationStarted = true;
       }
     };
+    const failListener = (event: Electron.Event, errorCode: number, errorDescription: string, validatedURL: string, isMainFrame: boolean) => {
+      if (!error && isMainFrame) {
+        error = { errorCode, errorDescription, url: validatedURL };
+      }
+      if (!navigationStarted && isMainFrame) {
+        finishListener();
+      }
+    };
     const stopLoadingListener = () => {
       // By the time we get here, either 'finish' or 'fail' should have fired
       // if the navigation occurred. However, in some situations (e.g. when
@@ -433,11 +436,11 @@
 };
 
 WebContents.prototype.setWindowOpenHandler = function (handler: (details: Electron.HandlerDetails) => ({action: 'deny'} | {action: 'allow', overrideBrowserWindowOptions?: BrowserWindowConstructorOptions, outlivesOpener?: boolean})) {
   this._windowOpenHandler = handler;
 };
 
 WebContents.prototype._callWindowOpenHandler = function (event: Electron.Event, details: Electron.HandlerDetails): {browserWindowConstructorOptions: BrowserWindowConstructorOptions | null, outlivesOpener: boolean} {
   const defaultResponse = {
     browserWindowConstructorOptions: null,
     outlivesOpener: false
   };

spec/api-web-contents-spec.ts

@@ -519,6 +519,10 @@ describe('webContents module', () => {
       await expect(w.loadURL('file:non-existent')).to.eventually.be.rejected();
       await expect(w.loadURL('file:non-existent')).to.eventually.be.rejected();
     });
+
+    it('invalid URL load rejects', async () => {
+      await expect(w.loadURL('invalidURL')).to.eventually.be.rejected();
+    });
   });
 
   describe('getFocusedWebContents() API', () => {