Further improve the tests (#290)

The previous `:elixir_ls_test_process` approach was not reliable and seemed to
suffer from a race condition. Instead always manually start the server so we can
be in full control of the processes.

Unfortunately aliases are not well supported in umbrella projects so use
`cmd mix test` as specified in:

https://elixirforum.com/t/mix-task-aliases-and-umbrellas/12666

Author: axelson

apps/elixir_ls_utils/lib/wire_protocol.ex

@@ -10,17 +10,8 @@ defmodule ElixirLS.Utils.WireProtocol do
     IO.binwrite(pid, "Content-Length: #{byte_size(body)}\r\n\r\n" <> body)
   end
 
-  case Mix.env() do
-    :test ->
-      defp io_dest do
-        Process.whereis(:raw_user) || Process.whereis(:elixir_ls_test_process) ||
-          Process.group_leader()
-      end
-
-    _ ->
-      defp io_dest do
-        Process.whereis(:raw_user) || Process.group_leader()
-      end
+  defp io_dest do
+    Process.whereis(:raw_user) || Process.group_leader()
   end
 
   def io_intercepted? do

apps/language_server/lib/language_server/build.ex

@@ -166,7 +166,7 @@ defmodule ElixirLS.LanguageServer.Build do
     end
   end
 
-  defp load_all_modules do
+  def load_all_modules do
     apps =
       cond do
         Mix.Project.umbrella?() ->

apps/language_server/mix.exs

@@ -10,6 +10,7 @@ defmodule ElixirLS.LanguageServer.Mixfile do
       config_path: "../../config/config.exs",
       deps_path: "../../deps",
       lockfile: "../../mix.lock",
+      aliases: aliases(),
       elixirc_paths: elixirc_paths(Mix.env()),
       build_embedded: false,
       start_permanent: true,
@@ -33,6 +34,12 @@ defmodule ElixirLS.LanguageServer.Mixfile do
     ]
   end
 
+  defp aliases do
+    [
+      test: "test --no-start"
+    ]
+  end
+
   defp elixirc_paths(:test), do: ["lib", "test/support"]
   defp elixirc_paths(_), do: ["lib"]
 end

apps/language_server/test/providers/completion_test.exs

@@ -19,6 +19,18 @@ defmodule ElixirLS.LanguageServer.Providers.CompletionTest do
     "command" => "editor.action.triggerParameterHints"
   }
 
+  setup context do
+    ElixirLS.LanguageServer.Build.load_all_modules()
+
+    unless context[:skip_server] do
+      server = ElixirLS.LanguageServer.Test.ServerTestHelpers.start_server()
+
+      {:ok, %{server: server}}
+    else
+      :ok
+    end
+  end
+
   test "returns all Logger completions on normal require" do
     text = """
     defmodule MyModule do

apps/language_server/test/providers/workspace_symbols_test.exs

@@ -2,14 +2,12 @@ defmodule ElixirLS.LanguageServer.Providers.WorkspaceSymbolsTest do
   use ExUnit.Case, async: false
   alias ElixirLS.LanguageServer.Providers.WorkspaceSymbols
 
-  @server_name WorkspaceSymbolsTestServer
-
   setup do
     alias ElixirLS.Utils.PacketCapture
     packet_capture = start_supervised!({PacketCapture, self()})
-    Process.register(packet_capture, :elixir_ls_test_process)
 
-    {:ok, pid} = WorkspaceSymbols.start_link(name: @server_name)
+    {:ok, pid} = WorkspaceSymbols.start_link(name: nil)
+    Process.group_leader(pid, packet_capture)
 
     state = :sys.get_state(pid)
 
@@ -29,23 +27,23 @@ defmodule ElixirLS.LanguageServer.Providers.WorkspaceSymbolsTest do
       }
     end)
 
-    WorkspaceSymbols.notify_build_complete(@server_name)
+    WorkspaceSymbols.notify_build_complete(pid)
 
     wait_until_indexed(pid)
 
-    {:ok, %{}}
+    {:ok, server: pid}
   end
 
-  test "empty query" do
-    assert {:ok, []} == WorkspaceSymbols.symbols("", @server_name)
+  test "empty query", %{server: server} do
+    assert {:ok, []} == WorkspaceSymbols.symbols("", server)
 
     assert_receive %{
       "method" => "window/logMessage",
       "params" => %{"message" => "[ElixirLS WorkspaceSymbols] Updating index..."}
     }
   end
 
-  test "returns modules" do
+  test "returns modules", %{server: server} do
     assert {:ok,
             [
               %{
@@ -56,7 +54,7 @@ defmodule ElixirLS.LanguageServer.Providers.WorkspaceSymbolsTest do
                 },
                 name: "ElixirLS.LanguageServer.Fixtures.WorkspaceSymbols"
               }
-            ]} = WorkspaceSymbols.symbols("ElixirLS.LanguageServer.Fixtures.", @server_name)
+            ]} = WorkspaceSymbols.symbols("ElixirLS.LanguageServer.Fixtures.", server)
 
     assert uri |> String.ends_with?("test/support/fixtures/workspace_symbols.ex")
 
@@ -70,12 +68,12 @@ defmodule ElixirLS.LanguageServer.Providers.WorkspaceSymbolsTest do
                 },
                 name: "ElixirLS.LanguageServer.Fixtures.WorkspaceSymbols"
               }
-            ]} = WorkspaceSymbols.symbols("work", @server_name)
+            ]} = WorkspaceSymbols.symbols("work", server)
 
     assert uri |> String.ends_with?("test/support/fixtures/workspace_symbols.ex")
   end
 
-  test "returns functions" do
+  test "returns functions", %{server: server} do
     assert {
              :ok,
              [
@@ -123,7 +121,7 @@ defmodule ElixirLS.LanguageServer.Providers.WorkspaceSymbolsTest do
                  name: "f ElixirLS.LanguageServer.Fixtures.WorkspaceSymbols.__info__/1"
                }
              ]
-           } = WorkspaceSymbols.symbols("f ElixirLS.LanguageServer.Fixtures.", @server_name)
+           } = WorkspaceSymbols.symbols("f ElixirLS.LanguageServer.Fixtures.", server)
 
     assert uri |> String.ends_with?("test/support/fixtures/workspace_symbols.ex")
 
@@ -137,12 +135,12 @@ defmodule ElixirLS.LanguageServer.Providers.WorkspaceSymbolsTest do
                 },
                 name: "f ElixirLS.LanguageServer.Fixtures.WorkspaceSymbols.some_function/1"
               }
-            ]} = WorkspaceSymbols.symbols("f fun", @server_name)
+            ]} = WorkspaceSymbols.symbols("f fun", server)
 
     assert uri |> String.ends_with?("test/support/fixtures/workspace_symbols.ex")
   end
 
-  test "returns types" do
+  test "returns types", %{server: server} do
     assert {
              :ok,
              [
@@ -162,7 +160,7 @@ defmodule ElixirLS.LanguageServer.Providers.WorkspaceSymbolsTest do
                  name: "t ElixirLS.LanguageServer.Fixtures.WorkspaceSymbols.some_opaque_type/0"
                }
              ]
-           } = WorkspaceSymbols.symbols("t ElixirLS.LanguageServer.Fixtures.", @server_name)
+           } = WorkspaceSymbols.symbols("t ElixirLS.LanguageServer.Fixtures.", server)
 
     assert uri |> String.ends_with?("test/support/fixtures/workspace_symbols.ex")
 
@@ -178,12 +176,12 @@ defmodule ElixirLS.LanguageServer.Providers.WorkspaceSymbolsTest do
                  name: "t ElixirLS.LanguageServer.Fixtures.WorkspaceSymbols.some_opaque_type/0"
                }
              ]
-           } = WorkspaceSymbols.symbols("t opa", @server_name)
+           } = WorkspaceSymbols.symbols("t opa", server)
 
     assert uri |> String.ends_with?("test/support/fixtures/workspace_symbols.ex")
   end
 
-  test "returns callbacks" do
+  test "returns callbacks", %{server: server} do
     assert {
              :ok,
              [
@@ -203,7 +201,7 @@ defmodule ElixirLS.LanguageServer.Providers.WorkspaceSymbolsTest do
                  name: "c ElixirLS.LanguageServer.Fixtures.WorkspaceSymbols.some_macrocallback/1"
                }
              ]
-           } = WorkspaceSymbols.symbols("c ElixirLS.LanguageServer.Fixtures.", @server_name)
+           } = WorkspaceSymbols.symbols("c ElixirLS.LanguageServer.Fixtures.", server)
 
     assert uri |> String.ends_with?("test/support/fixtures/workspace_symbols.ex")
 
@@ -217,7 +215,7 @@ defmodule ElixirLS.LanguageServer.Providers.WorkspaceSymbolsTest do
                 },
                 name: "c ElixirLS.LanguageServer.Fixtures.WorkspaceSymbols.some_macrocallback/1"
               }
-            ]} = WorkspaceSymbols.symbols("c macr", @server_name)
+            ]} = WorkspaceSymbols.symbols("c macr", server)
 
     assert uri |> String.ends_with?("test/support/fixtures/workspace_symbols.ex")
   end

apps/language_server/test/support/server_test_helpers.ex

@@ -1,15 +1,22 @@
 defmodule ElixirLS.LanguageServer.Test.ServerTestHelpers do
   import ExUnit.Callbacks, only: [start_supervised!: 1]
+
   alias ElixirLS.LanguageServer.Server
+  alias ElixirLS.LanguageServer.JsonRpc
+  alias ElixirLS.LanguageServer.Providers.WorkspaceSymbols
   alias ElixirLS.Utils.PacketCapture
 
   def start_server do
-    server = start_supervised!({Server, nil})
     packet_capture = start_supervised!({PacketCapture, self()})
+
+    server = start_supervised!({Server, nil})
     Process.group_leader(server, packet_capture)
 
-    Process.whereis(ElixirLS.LanguageServer.Providers.WorkspaceSymbols)
-    |> Process.group_leader(packet_capture)
+    json_rpc = start_supervised!({JsonRpc, name: JsonRpc})
+    Process.group_leader(json_rpc, packet_capture)
+
+    workspace_symbols = start_supervised!({WorkspaceSymbols, []})
+    Process.group_leader(workspace_symbols, packet_capture)
 
     server
   end

mix.exs

@@ -4,6 +4,7 @@ defmodule ElixirLS.Mixfile do
   def project do
     [
       apps_path: "apps",
+      aliases: aliases(),
       build_embedded: Mix.env() == :prod,
       start_permanent: Mix.env() == :prod,
       build_per_environment: false,
@@ -27,4 +28,10 @@ defmodule ElixirLS.Mixfile do
   defp deps do
     []
   end
+
+  defp aliases do
+    [
+      test: "cmd mix test"
+    ]
+  end
 end