Add a world argument to tab.run_js_async

qutebrowser/browser/browsertab.py

@@ -747,11 +747,17 @@ class AbstractTab(QWidget):
         """
         raise NotImplementedError
 
-    def run_js_async(self, code, callback=None):
+    def run_js_async(self, code, callback=None, *, world=None):
         """Run javascript async.
 
         The given callback will be called with the result when running JS is
         complete.
+
+        Args:
+            code: The javascript code to run.
+            callback: The callback to call with the result, or None.
+            world: An int world ID to run the JS in the main world or in another
+                   isolated world.
         """
         raise NotImplementedError
 

qutebrowser/browser/webengine/webenginetab.py

@@ -475,14 +475,24 @@ class WebEngineTab(browsertab.AbstractTab):
         else:
             self._widget.page().toHtml(callback)
 
-    def run_js_async(self, code, callback=None):
-        world = QWebEngineScript.ApplicationWorld
+    def run_js_async(self, code, callback=None, *, world=None):
+        if world is None:
+            world_id = QWebEngineScript.ApplicationWorld
+        else:
+            # We need to make this sure here, as otherwise we get an unexpected
+            # TypeError later...
+            if not isinstance(world, int):
+                raise TypeError("Expected int as world id, got {!r}".format(
+                    world))
+            world_id = world
         try:
             if callback is None:
-                self._widget.page().runJavaScript(code, world)
+                self._widget.page().runJavaScript(code, world_id)
             else:
-                self._widget.page().runJavaScript(code, world, callback)
+                self._widget.page().runJavaScript(code, world_id, callback)
         except TypeError:
+            if world is not None:
+                log.webview.warning("Ignoring world ID on Qt < 5.7")
             # Qt < 5.7
             if callback is None:
                 self._widget.page().runJavaScript(code)

qutebrowser/browser/webkit/webkittab.py

@@ -621,7 +621,9 @@ class WebKitTab(browsertab.AbstractTab):
         else:
             callback(frame.toHtml())
 
-    def run_js_async(self, code, callback=None):
+    def run_js_async(self, code, callback=None, *, world=None):
+        if world is not None:
+            log.webview.warning("Ignoring world ID {}".format(world))
         result = self._widget.page().mainFrame().evaluateJavaScript(code)
         if callback is not None:
             callback(result)