Send end progress when request is cancelled.

apps/els_lsp/src/els_background_job.erl

@@ -155,6 +155,8 @@ handle_cast(_Request, State) ->
 
 -spec handle_info(any(), any()) ->
     {noreply, state()}.
+handle_info({exec, InternalState}, State) ->
+    handle_info(exec, State#{internal_state => InternalState});
 handle_info(exec, State) ->
     #{
         config := #{entries := Entries, task := Task} = Config,
@@ -171,22 +173,32 @@ handle_info(exec, State) ->
             notify_end(Token, Total, ProgressEnabled),
             {stop, normal, State};
         [Entry | Rest] ->
-            NewInternalState = Task(Entry, InternalState),
-            notify_report(
-                Token,
-                Current,
-                Step,
-                Total,
-                ProgressEnabled,
-                ShowPercentages
+            MainPid = self(),
+            %% Run the task in a separate process so main process
+            %% is not blocked from receiving messages, needed for stopping
+            %% job.
+            spawn_link(
+                fun() ->
+                    NewInternalState = Task(Entry, InternalState),
+                    notify_report(
+                        Token,
+                        Current,
+                        Step,
+                        Total,
+                        ProgressEnabled,
+                        ShowPercentages
+                    ),
+                    MainPid ! {exec, NewInternalState}
+                end
             ),
-            self() ! exec,
             {noreply, State#{
                 config => Config#{entries => Rest},
-                current => Current + 1,
-                internal_state => NewInternalState
+                current => Current + 1
             }}
     end;
+%% Allow the terminate function to be called if the spawned child processes dies
+handle_info({'EXIT', _Sender, Reason}, State) when Reason /= normal ->
+    {stop, Reason, State};
 handle_info(_Request, State) ->
     {noreply, State}.
 

apps/els_lsp/src/els_server.erl

@@ -230,6 +230,16 @@ handle_request(
         {RequestId, Job} when RequestId =:= Id ->
             ?LOG_DEBUG("[SERVER] Cancelling request [id=~p] [job=~p]", [Id, Job]),
             els_background_job:stop(Job),
+            Error = #{
+                code => ?ERR_REQUEST_CANCELLED,
+                message => <<"Request was cancelled">>
+            },
+            ErrorResponse = els_protocol:error(RequestId, Error),
+            ?LOG_DEBUG(
+                "[SERVER] Sending error response [response=~p]",
+                [ErrorResponse]
+            ),
+            send(ErrorResponse, State0),
             State0#{
                 pending => lists:keydelete(Id, 1, Pending),
                 in_progress => lists:keydelete(Job, 2, InProgress)
@@ -272,8 +282,8 @@ handle_request(
         {async, Uri, BackgroundJob, State} ->
             RequestId = maps:get(<<"id">>, Request),
             ?LOG_DEBUG(
-                "[SERVER] Suspending response [background_job=~p]",
-                [BackgroundJob]
+                "[SERVER] Suspending response [background_job=~p id=~p]",
+                [BackgroundJob, RequestId]
             ),
             NewPending = [{RequestId, BackgroundJob} | Pending],
             State#{

apps/els_lsp/test/els_progress_SUITE.erl

@@ -20,7 +20,8 @@
 %%==============================================================================
 -export([
     sample_job/1,
-    failing_job/1
+    failing_job/1,
+    stop_job/1
 ]).
 
 %%==============================================================================
@@ -63,6 +64,16 @@ init_per_testcase(sample_job = TestCase, Config) ->
 init_per_testcase(failing_job = TestCase, Config) ->
     Task = fun(_, _) -> exit(fail) end,
     setup_mocks(Task),
+    [{task, Task} | els_test_utils:init_per_testcase(TestCase, Config)];
+init_per_testcase(stop_job = TestCase, Config) ->
+    Task = fun(_, _) ->
+        sample_job:task_called(),
+        timer:sleep(timer:seconds(100))
+    end,
+    setup_mocks(Task),
+    %% Bit of a hack, because meck only count history after mocked function returns it seems,
+    %% and the above function will not return.
+    meck:expect(sample_job, task_called, fun() -> ok end),
     [{task, Task} | els_test_utils:init_per_testcase(TestCase, Config)].
 
 -spec end_per_testcase(atom(), config()) -> ok.
@@ -92,6 +103,17 @@ failing_job(_Config) ->
     ?assertEqual(1, meck:num_calls(sample_job, on_error, '_')),
     ok.
 
+-spec stop_job(config()) -> ok.
+stop_job(_Config) ->
+    {ok, Pid} = new_background_job(),
+    meck:wait(sample_job, task_called, '_', 5000),
+    els_background_job:stop(Pid),
+    wait_for_completion(Pid),
+    ?assertEqual(1, meck:num_calls(sample_job, task_called, '_')),
+    ?assertEqual(0, meck:num_calls(sample_job, on_complete, '_')),
+    ?assertEqual(1, meck:num_calls(sample_job, on_error, '_')),
+    ok.
+
 %%==============================================================================
 %% Internal Functions
 %%==============================================================================