Auto merge of #10868 - frewsxcv:loadcancelled, r=Ms2ger

Add `NetworkError::LoadCancelled` variant.

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components/msg/constellation_msg.rs

@@ -400,4 +400,3 @@ pub enum ReferrerPolicy {
     OriginWhenCrossOrigin,
     UnsafeUrl,
 }
-

components/net/file_loader.rs

@@ -50,7 +50,7 @@ fn read_all(reader: &mut File, progress_chan: &ProgressSender, cancel_listener:
             ReadStatus::EOF => return Ok(LoadResult::Finished),
         }
     }
-    let _ = progress_chan.send(Done(Err(NetworkError::Internal("load cancelled".to_owned()))));
+    let _ = progress_chan.send(Done(Err(NetworkError::LoadCancelled)));
     Ok(LoadResult::Cancelled)
 }
 
@@ -92,7 +92,7 @@ pub fn factory(load_data: LoadData,
         if cancel_listener.is_cancelled() {
             if let Ok(progress_chan) = get_progress_chan(load_data, file_path,
                                                          senders, classifier, &[]) {
-                let _ = progress_chan.send(Done(Err(NetworkError::Internal("load cancelled".to_owned()))));
+                let _ = progress_chan.send(Done(Err(NetworkError::LoadCancelled)));
             }
             return;
         }

components/net/http_loader.rs

@@ -160,6 +160,7 @@ fn load_for_consumer(load_data: LoadData,
                 LoadErrorType::Ssl { .. } => send_error(error.url.clone(),
                                                         NetworkError::SslValidation(error.url),
                                                         start_chan),
+                LoadErrorType::Cancelled => send_error(error.url, NetworkError::LoadCancelled, start_chan),
                 _ => send_error(error.url, NetworkError::Internal(error.error.description().to_owned()), start_chan)
             }
         }
@@ -983,7 +984,7 @@ fn send_data<R: Read>(context: LoadContext,
 
     loop {
         if cancel_listener.is_cancelled() {
-            let _ = progress_chan.send(Done(Err(NetworkError::Internal("load cancelled".to_owned()))));
+            let _ = progress_chan.send(Done(Err(NetworkError::LoadCancelled)));
             return;
         }
 

components/net_traits/lib.rs

@@ -437,9 +437,9 @@ pub enum ConstellationMsg {
 /// Network errors that have to be exported out of the loaders
 #[derive(Clone, PartialEq, Eq, Debug, Deserialize, Serialize, HeapSizeOf)]
 pub enum NetworkError {
-    /// Could be any of the internal errors, like unsupported scheme, load
+    /// Could be any of the internal errors, like unsupported scheme, connection errors, etc.
-    /// cancellation, connection errors, etc.
     Internal(String),
+    LoadCancelled,
     /// SSL validation error that has to be handled in the HTML parser
     SslValidation(Url),
 }

tests/unit/net/resource_thread.rs

@@ -220,6 +220,6 @@ fn test_cancelled_listener() {
     let _ = body_sender.send(body);
     let response = receiver.recv().unwrap();
     assert_eq!(response.progress_port.recv().unwrap(),
-               ProgressMsg::Done(Err(NetworkError::Internal("load cancelled".to_owned()))));
+               ProgressMsg::Done(Err(NetworkError::LoadCancelled)));
     resource_thread.send(ControlMsg::Exit).unwrap();
 }