Auto merge of #10840 - ConnorGBrewster:window_alert, r=jdm

Implement alert dialogs

fix #10812

Implements alert dialogs using tinyfiledialogs

r? @jdm

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components/compositing/constellation.rs

@@ -805,6 +805,10 @@ impl<LTF: LayoutThreadFactory, STF: ScriptThreadFactory> Constellation<LTF, STF>
                 debug!("constellation got SetDocumentState message");
                 self.document_states.insert(pipeline_id, state);
             }
+            Request::Script(FromScriptMsg::Alert(pipeline_id, message, sender)) => {
+                debug!("constellation got Alert message");
+                self.handle_alert(pipeline_id, message, sender);
+            }
 
 
             // Messages from layout thread
@@ -1080,6 +1084,44 @@ impl<LTF: LayoutThreadFactory, STF: ScriptThreadFactory> Constellation<LTF, STF>
         }
     }
 
+    fn handle_alert(&mut self, pipeline_id: PipelineId, message: String, sender: IpcSender<bool>) {
+        let display_alert_dialog = if prefs::get_pref("dom.mozbrowser.enabled").as_boolean().unwrap_or(false) {
+            let parent_pipeline_info = self.pipelines.get(&pipeline_id).and_then(|source| source.parent_info);
+            if let Some(_) = parent_pipeline_info {
+                let root_pipeline_id = self.root_frame_id
+                    .and_then(|root_frame_id| self.frames.get(&root_frame_id))
+                    .map(|root_frame| root_frame.current);
+
+                let ancestor_info = self.get_root_pipeline_and_containing_parent(&pipeline_id);
+                if let Some(ancestor_info) = ancestor_info {
+                    if root_pipeline_id == Some(ancestor_info.0) {
+                        match root_pipeline_id.and_then(|pipeline_id| self.pipelines.get(&pipeline_id)) {
+                            Some(root_pipeline) => {
+                                // https://developer.mozilla.org/en-US/docs/Web/Events/mozbrowsershowmodalprompt
+                                let event = MozBrowserEvent::ShowModalPrompt("alert".to_owned(), "Alert".to_owned(),
+                                                                             String::from(message), "".to_owned());
+                                root_pipeline.trigger_mozbrowser_event(ancestor_info.1, event);
+                            }
+                            None => return warn!("Alert sent to Pipeline {:?} after closure.", root_pipeline_id),
+                        }
+                    } else {
+                        warn!("A non-current frame is trying to show an alert.")
+                    }
+                }
+                false
+            } else {
+                true
+            }
+        } else {
+            true
+        };
+
+        let result = sender.send(display_alert_dialog);
+        if let Err(e) = result {
+            self.handle_send_error(pipeline_id, e);
+        }
+    }
+
     fn handle_load_url_msg(&mut self, source_id: PipelineId, load_data: LoadData) {
         self.load_url(source_id, load_data);
     }
@@ -1956,6 +1998,29 @@ impl<LTF: LayoutThreadFactory, STF: ScriptThreadFactory> Constellation<LTF, STF>
         }
     }
 
+    /// For a given pipeline, determine the iframe in the root pipeline that transitively contains
+    /// it. There could be arbitrary levels of nested iframes in between them.
+    fn get_root_pipeline_and_containing_parent(&self, pipeline_id: &PipelineId) -> Option<(PipelineId, SubpageId)> {
+        if let Some(pipeline) = self.pipelines.get(pipeline_id) {
+            if let Some(mut ancestor_info) = pipeline.parent_info {
+                if let Some(mut ancestor) = self.pipelines.get(&ancestor_info.0) {
+                    while let Some(next_info) = ancestor.parent_info {
+                        ancestor_info = next_info;
+                        ancestor = match self.pipelines.get(&ancestor_info.0) {
+                            Some(ancestor) => ancestor,
+                            None => {
+                                warn!("Get parent pipeline before root via closed pipeline {:?}.", ancestor_info.0);
+                                return None;
+                            },
+                        };
+                    }
+                    return Some(ancestor_info);
+                }
+            }
+        }
+        None
+    }
+
     // https://developer.mozilla.org/en-US/docs/Web/Events/mozbrowserlocationchange
     // Note that this is a no-op if the pipeline is not an immediate child iframe of the root
     fn trigger_mozbrowserlocationchange(&self, pipeline_id: PipelineId) {
@@ -1987,19 +2052,15 @@ impl<LTF: LayoutThreadFactory, STF: ScriptThreadFactory> Constellation<LTF, STF>
     fn trigger_mozbrowsererror(&self, pipeline_id: PipelineId, reason: String, backtrace: String) {
         if !prefs::get_pref("dom.mozbrowser.enabled").as_boolean().unwrap_or(false) { return; }
 
-        if let Some(pipeline) = self.pipelines.get(&pipeline_id) {
-            if let Some(mut ancestor_info) = pipeline.parent_info {
-                if let Some(mut ancestor) = self.pipelines.get(&ancestor_info.0) {
-                    while let Some(next_info) = ancestor.parent_info {
-                        ancestor_info = next_info;
-                        ancestor = match self.pipelines.get(&ancestor_info.0) {
-                            Some(ancestor) => ancestor,
-                            None => return warn!("Mozbrowsererror via closed pipeline {:?}.", ancestor_info.0),
-                        };
-                    }
+        let ancestor_info = self.get_root_pipeline_and_containing_parent(&pipeline_id);
+
+        if let Some(ancestor_info) = ancestor_info {
+            match self.pipelines.get(&ancestor_info.0) {
+                Some(ancestor) => {
                     let event = MozBrowserEvent::Error(MozBrowserErrorType::Fatal, Some(reason), Some(backtrace));
                     ancestor.trigger_mozbrowser_event(ancestor_info.1, event);
-                }
+                },
+                None => return warn!("Mozbrowsererror via closed pipeline {:?}.", ancestor_info.0),
             }
         }
     }

components/script/Cargo.toml

@@ -13,6 +13,9 @@ path = "lib.rs"
 [features]
 debugmozjs = ['js/debugmozjs']
 
+[target.'cfg(any(target_os = "macos", target_os = "linux"))'.dependencies]
+tinyfiledialogs = {git = "https://github.com/jdm/tinyfiledialogs"}
+
 [dependencies]
 plugins = {path = "../plugins"}
 util = {path = "../util"}

components/script/dom/window.rs

@@ -60,7 +60,7 @@ use script_thread::SendableMainThreadScriptChan;
 use script_thread::{MainThreadScriptChan, MainThreadScriptMsg, RunnableWrapper};
 use script_traits::{ConstellationControlMsg, UntrustedNodeAddress};
 use script_traits::{DocumentState, MsDuration, ScriptToCompositorMsg, TimerEvent, TimerEventId};
-use script_traits::{MozBrowserEvent, ScriptMsg as ConstellationMsg, TimerEventRequest, TimerSource};
+use script_traits::{ScriptMsg as ConstellationMsg, TimerEventRequest, TimerSource};
 use std::ascii::AsciiExt;
 use std::borrow::ToOwned;
 use std::cell::Cell;
@@ -86,6 +86,8 @@ use task_source::networking::NetworkingTaskSource;
 use task_source::user_interaction::UserInteractionTaskSource;
 use time;
 use timers::{IsInterval, OneshotTimerCallback, OneshotTimerHandle, OneshotTimers, TimerCallback};
+#[cfg(any(target_os = "macos", target_os = "linux"))]
+use tinyfiledialogs::{self, MessageBoxIcon};
 use url::Url;
 use util::geometry::{self, MAX_RECT};
 use util::str::{DOMString, HTML_SPACE_CHARACTERS};
@@ -352,6 +354,16 @@ impl Window {
     }
 }
 
+#[cfg(any(target_os = "macos", target_os = "linux"))]
+fn display_alert_dialog(message: &str) {
+    tinyfiledialogs::message_box_ok("Alert!", message, MessageBoxIcon::Warning);
+}
+
+#[cfg(not(any(target_os = "macos", target_os = "linux")))]
+fn display_alert_dialog(_message: &str) {
+    // tinyfiledialogs not supported on Windows
+}
+
 // https://html.spec.whatwg.org/multipage/#atob
 pub fn base64_btoa(input: DOMString) -> Fallible<DOMString> {
     // "The btoa() method must throw an InvalidCharacterError exception if
@@ -434,10 +446,13 @@ impl WindowMethods for Window {
         stdout.flush().unwrap();
         stderr.flush().unwrap();
 
-        // https://developer.mozilla.org/en-US/docs/Web/Events/mozbrowsershowmodalprompt
-        let event = MozBrowserEvent::ShowModalPrompt("alert".to_owned(), "Alert".to_owned(),
-                                                     String::from(s), "".to_owned());
-        self.Document().trigger_mozbrowser_event(event);
+        let (sender, receiver) = ipc::channel().unwrap();
+        self.constellation_chan().0.send(ConstellationMsg::Alert(self.pipeline(), s.to_string(), sender)).unwrap();
+
+        let should_display_alert_dialog = receiver.recv().unwrap();
+        if should_display_alert_dialog {
+            display_alert_dialog(&s);
+        }
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-window-close

components/script/lib.rs

@@ -73,6 +73,8 @@ extern crate smallvec;
 #[macro_use]
 extern crate style;
 extern crate time;
+#[cfg(any(target_os = "macos", target_os = "linux"))]
+extern crate tinyfiledialogs;
 extern crate unicase;
 extern crate url;
 #[macro_use]

components/script_traits/script_msg.rs

@@ -81,4 +81,6 @@ pub enum ScriptMsg {
     SetDocumentState(PipelineId, DocumentState),
     /// Update the pipeline Url, which can change after redirections.
     SetFinalUrl(PipelineId, Url),
+    /// Check if an alert dialog box should be presented
+    Alert(PipelineId, String, IpcSender<bool>),
 }

tests/wpt/mozilla/tests/mozilla/mozbrowser/mozbrowsershowmodalprompt_event.html

@@ -16,4 +16,16 @@
         }));
         document.body.appendChild(iframe);
     });
+
+    async_test(function(t) {
+        var iframe = document.createElement("iframe");
+        iframe.mozbrowser = "true";
+        iframe.src = "mozbrowsershowmodalprompt_event_nested_iframe.html";
+        iframe.addEventListener("mozbrowsershowmodalprompt", t.step_func(e => {
+            assert_equals(e.detail.promptType, "alert");
+            assert_equals(e.detail.message, "my alert message");
+            t.done();
+        }));
+        document.body.appendChild(iframe);
+    }, "mozbrowsershowmodalprompt event from nested iframes triggering an alert");
 </script>

tests/wpt/mozilla/tests/mozilla/mozbrowser/mozbrowsershowmodalprompt_event_nested_iframe.html

@@ -0,0 +1,5 @@
+<html>
+    <body>
+        <iframe src="mozbrowsershowmodalprompt_event_iframe.html" />
+    </body>
+</html>