webelem: Make it possible to use is_visible with unwrapped elements.

qutebrowser/browser/webelem.py

@@ -164,58 +164,11 @@ class WebElementWrapper(collections.abc.MutableMapping):
         Return:
             True if the element is visible, False otherwise.
         """
-        self._check_vanished()
+        return is_visible(self._elem, mainframe)
-        # CSS attributes which hide an element
-        hidden_attributes = {
-            'visibility': 'hidden',
-            'display': 'none',
-        }
-        for k, v in hidden_attributes.items():
-            if self._elem.styleProperty(k, QWebElement.ComputedStyle) == v:
-                return False
-        geometry = self._elem.geometry()
-        if not geometry.isValid() and geometry.x() == 0:
-            # Most likely an invisible link
-            return False
-        # First check if the element is visible on screen
-        elem_rect = self.rect_on_view()
-        if elem_rect.isValid():
-            visible_on_screen = mainframe.geometry().intersects(elem_rect)
-        else:
-            # We got an invalid rectangle (width/height 0/0 probably), but this
-            # can still be a valid link.
-            visible_on_screen = mainframe.geometry().contains(
-                elem_rect.topLeft())
-        # Then check if it's visible in its frame if it's not in the main
-        # frame.
-        elem_frame = self._elem.webFrame()
-        elem_rect = self._elem.geometry()
-        framegeom = QRect(elem_frame.geometry())
-        if not framegeom.isValid():
-            visible_in_frame = False
-        elif elem_frame.parentFrame() is not None:
-            framegeom.moveTo(0, 0)
-            framegeom.translate(elem_frame.scrollPosition())
-            if elem_rect.isValid():
-                visible_in_frame = framegeom.intersects(elem_rect)
-            else:
-                # We got an invalid rectangle (width/height 0/0 probably), but
-                # this can still be a valid link.
-                visible_in_frame = framegeom.contains(elem_rect.topLeft())
-        else:
-            visible_in_frame = visible_on_screen
-        return all([visible_on_screen, visible_in_frame])
 
     def rect_on_view(self):
         """Get the geometry of the element relative to the webview."""
-        self._check_vanished()
+        return rect_on_view(self._elem)
-        frame = self._elem.webFrame()
-        rect = QRect(self._elem.geometry())
-        while frame is not None:
-            rect.translate(frame.geometry().topLeft())
-            rect.translate(frame.scrollPosition() * -1)
-            frame = frame.parentFrame()
-        return rect
 
     def is_writable(self):
         """Check whether an element is writable."""
@@ -381,3 +334,79 @@ def focus_elem(frame):
     """
     elem = frame.findFirstElement(SELECTORS[Group.focus])
     return WebElementWrapper(elem)
+
+
+def rect_on_view(elem):
+    """Get the geometry of the element relative to the webview.
+
+    We need this as a standalone function (as opposed to a WebElementWrapper
+    method) because we want to run is_visible before wrapping when hinting for
+    performance reasons.
+
+    Args:
+        elem: The QWebElement to get the rect for.
+    """
+    if elem.isNull():
+        raise IsNullError("Got called on a null element!")
+    frame = elem.webFrame()
+    rect = QRect(elem.geometry())
+    while frame is not None:
+        rect.translate(frame.geometry().topLeft())
+        rect.translate(frame.scrollPosition() * -1)
+        frame = frame.parentFrame()
+    return rect
+
+
+def is_visible(elem, mainframe):
+    """Check if the given element is visible in the frame.
+
+    We need this as a standalone function (as opposed to a WebElementWrapper
+    method) because we want to check this before wrapping when hinting for
+    performance reasons.
+
+    Args:
+        elem: The QWebElement to check.
+        mainframe: The QWebFrame in which the element should be visible.
+    """
+    if elem.isNull():
+        raise IsNullError("Got called on a null element!")
+    # CSS attributes which hide an element
+    hidden_attributes = {
+        'visibility': 'hidden',
+        'display': 'none',
+    }
+    for k, v in hidden_attributes.items():
+        if elem.styleProperty(k, QWebElement.ComputedStyle) == v:
+            return False
+    geometry = elem.geometry()
+    if not geometry.isValid() and geometry.x() == 0:
+        # Most likely an invisible link
+        return False
+    # First check if the element is visible on screen
+    elem_rect = rect_on_view(elem)
+    if elem_rect.isValid():
+        visible_on_screen = mainframe.geometry().intersects(elem_rect)
+    else:
+        # We got an invalid rectangle (width/height 0/0 probably), but this
+        # can still be a valid link.
+        visible_on_screen = mainframe.geometry().contains(
+            elem_rect.topLeft())
+    # Then check if it's visible in its frame if it's not in the main
+    # frame.
+    elem_frame = elem.webFrame()
+    elem_rect = elem.geometry()
+    framegeom = QRect(elem_frame.geometry())
+    if not framegeom.isValid():
+        visible_in_frame = False
+    elif elem_frame.parentFrame() is not None:
+        framegeom.moveTo(0, 0)
+        framegeom.translate(elem_frame.scrollPosition())
+        if elem_rect.isValid():
+            visible_in_frame = framegeom.intersects(elem_rect)
+        else:
+            # We got an invalid rectangle (width/height 0/0 probably), but
+            # this can still be a valid link.
+            visible_in_frame = framegeom.contains(elem_rect.topLeft())
+    else:
+        visible_in_frame = visible_on_screen
+    return all([visible_on_screen, visible_in_frame])