panic when trying to load url which does not begin with http(s)

[zmike]

    fn on_load_url_window_event(&mut self, url_string: String) {
        debug!("osmain: loading URL `{}`", url_string);
        self.got_load_complete_message = false;
        let root_pipeline_id = match self.scene.root {
            Some(ref layer) => layer.get_pipeline_id(),
            None => panic!("Compositor: Received WindowEvent::LoadUrl without initialized compositor \
                           layers"),
        };

    vvvvv this line causes a panic

        let url = Url::parse(&url_string).unwrap();
        self.window.set_page_url(url.clone());

        let msg = ConstellationMsg::LoadUrl(root_pipeline_id, LoadData::new(url));
        let ConstellationChan(ref chan) = self.constellation_chan;
        chan.send(msg).unwrap()
    }

[jdm]

Isn't that usually the responsibility of the frontend to fix up?

[zmike]

Adding it, possibly. But the engine still shouldn't crash if it can't parse a url.

[brunoabinader]

Will get on that, if no one else already started doing so :-)

[Manishearth]

We could also be trying to load a file called mozilla.org.

[zmike]

According to resources linked by @jdm, this is impossible since it would be a relative path file open which is not something that web browsers are capable of.

Mainly the fix I'm looking for here is to check the result and then send an error back to the window. I've added the required error functionality in #6175 which is in the reviewing queue.

[zmike]

#6175 has merged, so sending the appropriate error (ADDRESS_INVALID I think) should basically be a one-liner.