feat(page): add Page.setJavaScriptEnabled for WebKit (#125)

src/frames.ts

@@ -471,8 +471,9 @@ export class Frame {
     // In case of multiple sessions to the same target, there's a race between
     // connections so we might end up creating multiple isolated worlds.
     // We can use either.
-    if (!world.context)
-      this._setContext(worldType, context);
+    if (world.context)
+      this._setContext(worldType, null);
+    this._setContext(worldType, context);
   }
 
   _contextDestroyed(context: js.ExecutionContext) {

src/webkit/Page.ts

@@ -348,6 +348,13 @@ export class Page extends EventEmitter {
     await this._session.send('Page.setBootstrapScript', { source });
   }
 
+  async setJavaScriptEnabled(enabled: boolean) {
+    if (this._javascriptEnabled === enabled)
+      return;
+    this._javascriptEnabled = enabled;
+    await this._session.send('Emulation.setJavaScriptEnabled', { enabled });
+  }
+
   async setCacheEnabled(enabled: boolean = true) {
     await this._frameManager.networkManager().setCacheEnabled(enabled);
   }

test/page.spec.js

@@ -831,12 +831,15 @@ module.exports.addTests = function({testRunner, expect, headless, playwright, FF
   });
 
   describe('Page.setJavaScriptEnabled', function() {
-    it.skip(WEBKIT)('should work', async({page, server}) => {
+    it('should work', async({page, server}) => {
       await page.setJavaScriptEnabled(false);
       await page.goto('data:text/html, <script>var something = "forbidden"</script>');
       let error = null;
       await page.evaluate('something').catch(e => error = e);
-      expect(error.message).toContain('something is not defined');
+      if (WEBKIT)
+        expect(error.message).toContain('Can\'t find variable: something');
+      else
+        expect(error.message).toContain('something is not defined');
 
       await page.setJavaScriptEnabled(true);
       await page.goto('data:text/html, <script>var something = "forbidden"</script>');