browser.py 文件源码

def __getattr__(self, attr):
        """Route all other attribute requests into the parent object's browser. Black magic included

        Here is the explanation:
        If you call ``.elements`` on this object directly, it will correctly inject the parent
        locator. But if you call eg. ``element``, what will happen is that it will invoke the
        original method from underlying browser and that method's ``self`` is the underlying browser
        and not this wrapper. Therefore ``element`` would call the original ``elements`` without
        injecting the parent.

        What this getter does is that if you pull out a method, it detects that, unbinds the
        pure function and rebinds it to this wrapper. The method that came from the browser object
        is now executed not against the browser, but against this wrapper, enabling us to intercept
        every single ``elements`` call.
        """
        value = getattr(self._browser, attr)
        if inspect.ismethod(value):
            function = six.get_method_function(value)
            # Bind the function like it was defined on this class
            value = function.__get__(self, BrowserParentWrapper)
        return value