publish diagnostics for all open files

attach document version to diagnostics
without that on restart diagnostics are not cleared as we don't have old_diagnostics

Fixes elixir-lsp/vscode-elixir-ls#389

Author: lukaszsamson

apps/language_server/lib/language_server/diagnostics.ex

@@ -182,14 +182,9 @@ defmodule ElixirLS.LanguageServer.Diagnostics do
     end)
   end
 
-  def publish_file_diagnostics(uri, all_diagnostics, source_file) do
-    diagnostics =
-      all_diagnostics
-      |> Enum.filter(&(SourceFile.Path.to_uri(&1.file) == uri))
-      |> Enum.sort_by(fn %{position: position} -> position end)
-
+  def publish_file_diagnostics(uri, uri_diagnostics, source_file, version) do
     diagnostics_json =
-      for diagnostic <- diagnostics do
+      for diagnostic <- uri_diagnostics do
         severity =
           case diagnostic.severity do
             :error -> 1
@@ -211,11 +206,21 @@ defmodule ElixirLS.LanguageServer.Diagnostics do
           "source" => diagnostic.compiler_name
         }
       end
+      |> Enum.sort_by(& &1["range"]["start"])
 
-    JsonRpc.notify("textDocument/publishDiagnostics", %{
+    message = %{
       "uri" => uri,
       "diagnostics" => diagnostics_json
-    })
+    }
+
+    message =
+      if is_integer(version) do
+        Map.put(message, "version", version)
+      else
+        message
+      end
+
+    JsonRpc.notify("textDocument/publishDiagnostics", message)
   end
 
   def mixfile_diagnostic({file, line, message}, severity) do

apps/language_server/lib/language_server/server.ex

@@ -1178,17 +1178,41 @@ defmodule ElixirLS.LanguageServer.Server do
   end
 
   defp publish_diagnostics(new_diagnostics, old_diagnostics, source_files) do
-    files =
-      Enum.uniq(Enum.map(new_diagnostics, & &1.file) ++ Enum.map(old_diagnostics, & &1.file))
-
-    for file <- files,
-        uri = SourceFile.Path.to_uri(file),
-        do:
-          Diagnostics.publish_file_diagnostics(
-            uri,
-            new_diagnostics,
-            Map.get_lazy(source_files, uri, fn -> safely_read_file(file) end)
-          )
+    # we need to publish diagnostics for all files in new_diagnostics
+    # to clear diagnostics we need to push empty sets for old_diagnostics
+    # in case we missed something or restarted and don't have old_diagnostics
+    # we also push for all open files
+    uris_from_old_diagnostics = Enum.map(old_diagnostics, &(&1.file |> SourceFile.Path.to_uri()))
+
+    new_diagnostics_by_uri =
+      new_diagnostics
+      |> Enum.group_by(&(&1.file |> SourceFile.Path.to_uri()))
+
+    uris_from_new_diagnostics = Map.keys(new_diagnostics_by_uri)
+
+    uris_from_open_files = Map.keys(source_files)
+
+    uris_to_publish_diagnostics =
+      Enum.uniq(uris_from_old_diagnostics ++ uris_from_new_diagnostics ++ uris_from_open_files)
+
+    for uri <- uris_to_publish_diagnostics do
+      uri_diagnostics = Map.get(new_diagnostics_by_uri, uri, [])
+      # TODO store versions on compile/parse/dialyze?
+      version =
+        case source_files[uri] do
+          nil -> nil
+          file -> file.version
+        end
+
+      Diagnostics.publish_file_diagnostics(
+        uri,
+        uri_diagnostics,
+        Map.get_lazy(source_files, uri, fn -> safely_read_file(SourceFile.Path.from_uri(uri)) end),
+        version
+      )
+
+      # TODO dump diagnostics to file
+    end
   end
 
   defp show_version_warnings do

apps/language_server/test/dialyzer_test.exs

@@ -398,7 +398,9 @@ defmodule ElixirLS.LanguageServer.DialyzerTest do
       assert_receive notification("window/logMessage", %{"message" => "Compile took" <> _}), 5000
 
       # we should not receive Protocol has already been consolidated warnings here
-      refute_receive notification("textDocument/publishDiagnostics", _), 3000
+      refute_receive notification("textDocument/publishDiagnostics", %{"diagnostics" => [_ | _]}),
+                     3000
+
       wait_until_compiled(server)
     end)
   end

apps/language_server/test/server_test.exs

@@ -494,9 +494,9 @@ defmodule ElixirLS.LanguageServer.ServerTest do
         assert %SourceFile{dirty?: false, text: ^code, version: 1} =
                  Server.get_source_file(state, uri)
 
-        refute_receive notification("textDocument/publishDiagnostics", %{
+        assert_receive notification("textDocument/publishDiagnostics", %{
                          "uri" => ^uri,
-                         "diagnostics" => _
+                         "diagnostics" => []
                        }),
                        1000
 
@@ -799,9 +799,9 @@ defmodule ElixirLS.LanguageServer.ServerTest do
         fake_initialize(server)
         Server.receive_packet(server, did_open(uri, "elixir", 1, code))
 
-        refute_receive notification("textDocument/publishDiagnostics", %{
+        assert_receive notification("textDocument/publishDiagnostics", %{
                          "uri" => ^uri,
-                         "diagnostics" => _
+                         "diagnostics" => []
                        }),
                        1000