Fix formatter test (#154)

Previously the test was written for a version of the formatter that sent
back the full code text. Adjust test to expect only the changes to the
file. Also change the source text to be generally formatted.

Author: axelson

apps/language_server/test/server_test.exs

@@ -126,53 +126,50 @@ defmodule ElixirLS.LanguageServer.ServerTest do
     assert %{received_shutdown?: true} = :sys.get_state(server)
   end
 
-  # TODO: Fix this test for the incremental formatter
-  @tag :pending
-  test "formatter", %{server: server} do
+  test "incremental formatter", %{server: server} do
     in_fixture(__DIR__, "formatter", fn ->
       uri = Path.join([root_uri(), "file.ex"])
-      code = ~S(
+
+      code = """
       defmodule MyModule do
-      def my_fn do
-      foo "This should be split into two lines if reading options from .formatter.exs"
+        def my_fn do
+          foo("This should be split into two lines if reading options from .formatter.exs")
+        end
       end
-      end
-      )
+      """
 
       initialize(server)
       Server.receive_packet(server, did_open(uri, "elixir", 1, code))
-      Server.receive_packet(server, formatting_req(1, uri, %{}))
+      Server.receive_packet(server, formatting_req(2, uri, %{}))
 
       resp = assert_receive(%{"id" => 2}, 1000)
 
-      assert response(1, [
+      assert response(2, [
+               %{
+                 "newText" => "\n    ",
+                 "range" => %{
+                   "end" => %{"character" => 84, "line" => 2},
+                   "start" => %{"character" => 84, "line" => 2}
+                 }
+               },
                %{
-                 "newText" =>
-                   "defmodule MyModule do\n  def my_fn do\n    foo(\n      \"This should be split into two lines if reading options from .formatter.exs\"\n    )\n  end\nend\n",
+                 "newText" => "\n      ",
                  "range" => %{
-                   "end" => %{"character" => 6, "line" => 6},
-                   "start" => %{"character" => 0, "line" => 0}
+                   "end" => %{"character" => 8, "line" => 2},
+                   "start" => %{"character" => 8, "line" => 2}
                  }
                }
-             ]) = resp
+             ]) == resp
 
-      # Now try it in a subdirectory with its own .formatter.exs file.
+      # Now try it in a subdirectory with its own .formatter.exs file that does not define a max line length.
       subdir_uri = Path.join([root_uri(), "lib/file.ex"])
       Server.receive_packet(server, did_open(subdir_uri, "elixir", 1, code))
-      Server.receive_packet(server, formatting_req(2, subdir_uri, %{}))
+      Server.receive_packet(server, formatting_req(3, subdir_uri, %{}))
 
-      resp = assert_receive(%{"id" => 2}, 1000)
+      resp = assert_receive(%{"id" => 3}, 1000)
 
-      assert response(2, [
-               %{
-                 "newText" =>
-                   "defmodule MyModule do\n  def my_fn do\n    foo \"This should be split into two lines if reading options from .formatter.exs\"\n  end\nend\n",
-                 "range" => %{
-                   "end" => %{"character" => 6, "line" => 6},
-                   "start" => %{"character" => 0, "line" => 0}
-                 }
-               }
-             ]) = resp
+      # File is already formatted
+      assert response(3, []) == resp
     end)
   end