Avoid race conditions on ExUnit test suite

Author: José Valim

lib/ex_unit/test/ex_unit/callbacks_test.exs

@@ -1,103 +1,42 @@
 Code.require_file "../test_helper.exs", __DIR__
 
 defmodule ExUnit.CallbacksTest do
-  use ExUnit.Case, async: true
-
-  setup_all do
-    {:ok, [context: :setup_all]}
-  end
-
-  setup do
-    {:ok, [initial_setup: true]}
-  end
-
-  setup context do
-    assert context[:initial_setup]
-    assert context[:context] == :setup_all
-    {:ok, [context: :setup]}
-  end
-
-  setup context do
-    if Process.get(:ex_unit_callback) do
-      raise "ex_unit_callback was not cleaned"
-    else
-      Process.put(:ex_unit_callback, context[:test])
-    end
-    :ok
-  end
-
-  teardown context do
-    assert context[:context] == :setup
-    {:ok, context: :teardown}
-  end
-
-  teardown context do
-    assert Process.get(:ex_unit_callback) == context[:test]
-    Process.delete(:ex_unit_callback)
-    assert context[:context] == :teardown
-    :ok
-  end
-
-  teardown_all context do
-    assert context[:context] == :setup_all
-    :ok
-  end
+  use ExUnit.Case
 
   import ExUnit.CaptureIO
 
-  test "callbacks can run custom code" do
-    assert Process.get(:ex_unit_callback) == :"test callbacks can run custom code"
-  end
-
-  test "receives context from callback", context do
-    assert context[:context] == :setup
-  end
-
-  test "doesn't choke on setup errors" do
-    defmodule SetupTest do
+  test "callbacks run custom code with context" do
+    defmodule CallbacksTest do
       use ExUnit.Case
 
-      setup _ do
-        :ok = error
+      setup_all do
+        {:ok, [context: :setup_all]}
       end
 
-      test "ok" do
-        :ok
+      setup do
+        {:ok, [initial_setup: true]}
       end
 
-      defp error, do: :error
-    end
-
-    assert capture_io(fn -> ExUnit.run end) =~
-           "** (MatchError) no match of right hand side value: :error"
-  end
-
-  test "doesn't choke on setup_all errors" do
-    defmodule SetupAllTest do
-      use ExUnit.Case, async: false
-
-      setup_all _ do
-        :ok = error
+      setup context do
+        assert context[:initial_setup]
+        assert context[:context] == :setup_all
+        {:ok, [context: :setup]}
       end
 
-      test "ok" do
-        :ok
+      test "callbacks", context do
+        assert context[:context] == :setup
       end
-
-      defp error, do: :error
     end
 
-    ExUnit.configure(formatters: [ExUnit.CLIFormatter])
-
     assert capture_io(fn -> ExUnit.run end) =~
-           "** (MatchError) no match of right hand side value: :error"
+           "1 tests, 0 failures"
   end
 
-  test "doesn't choke on teardown errors" do
-    defmodule TeardownTest do
-      use ExUnit.Case, async: false
+  test "doesn't choke on setup errors" do
+    defmodule SetupTest do
+      use ExUnit.Case
 
-      teardown _ do
+      setup _ do
         :ok = error
       end
 
@@ -112,11 +51,11 @@ defmodule ExUnit.CallbacksTest do
            "** (MatchError) no match of right hand side value: :error"
   end
 
-  test "doesn't choke on teardown_all errors" do
-    defmodule TeardownAllTest do
+  test "doesn't choke on setup_all errors" do
+    defmodule SetupAllTest do
       use ExUnit.Case, async: false
 
-      teardown_all _ do
+      setup_all _ do
         :ok = error
       end
 
@@ -136,18 +75,13 @@ defmodule ExUnit.CallbacksTest do
       use ExUnit.Case, async: false
 
       test "ok" do
-        on_exit fn ->
-          :ok = error
-        end
-
+        on_exit fn -> :ok = error end
         :ok
       end
 
       defp error, do: :error
     end
 
-    ExUnit.configure(formatters: [ExUnit.CLIFormatter])
-
     assert capture_io(fn -> ExUnit.run end) =~
            "** (MatchError) no match of right hand side value: :error"
   end
@@ -157,21 +91,22 @@ defmodule ExUnit.CallbacksTest do
       use ExUnit.Case, async: false
 
       test "ok" do
-        on_exit fn ->
-          Process.exit(self(), :kill)
-        end
-
+        on_exit fn -> Process.exit(self(), :kill) end
         :ok
       end
     end
 
-    ExUnit.configure(formatters: [ExUnit.CLIFormatter])
     assert capture_io(fn -> ExUnit.run end) =~
            ">) killed"
   end
 
+  defp no_formatters! do
+    ExUnit.configure(formatters: [])
+    on_exit fn -> ExUnit.configure(formatters: [ExUnit.CLIFormatter]) end
+  end
+
   test "runs multiple on_exit exits and overrides by ref" do
-    defmodule OnExitOverrideTest do
+    defmodule OnExitSuccessTest do
       use ExUnit.Case, async: false
 
       setup do
@@ -182,12 +117,16 @@ defmodule ExUnit.CallbacksTest do
         on_exit {:overridden, 1}, fn ->
           IO.puts "on_exit 1 overridden -> not run"
         end
+
+        :ok
       end
 
       setup_all do
         on_exit fn ->
           IO.puts "on_exit setup_all run"
         end
+
+        :ok
       end
 
       test "ok" do
@@ -211,7 +150,7 @@ defmodule ExUnit.CallbacksTest do
       end
     end
 
-    ExUnit.configure(formatters: [ExUnit.CLIFormatter])
+    no_formatters!
     output = capture_io(fn -> ExUnit.run end)
 
     assert output =~ """
@@ -224,6 +163,45 @@ defmodule ExUnit.CallbacksTest do
 
     refute output =~ "not run"
   end
+
+  test "runs multiple on_exit on failure" do
+    defmodule OnExitFailureTest do
+      use ExUnit.Case, async: false
+
+      setup do
+        on_exit fn ->
+          IO.puts "on_exit setup run"
+        end
+
+        :ok
+      end
+
+      setup_all do
+        on_exit fn ->
+          IO.puts "on_exit setup_all run"
+        end
+
+        :ok
+      end
+
+      test "ok" do
+        on_exit fn ->
+          IO.puts "simple on_exit run"
+        end
+
+        flunk "oops"
+      end
+    end
+
+    no_formatters!
+    output = capture_io(fn -> ExUnit.run end)
+
+    assert output =~ """
+    simple on_exit run
+    on_exit setup run
+    on_exit setup_all run
+    """
+  end
 end
 
 defmodule ExUnit.CallbacksNoTests do
@@ -236,12 +214,4 @@ defmodule ExUnit.CallbacksNoTests do
   setup do
     raise "Never run"
   end
-
-  teardown do
-    raise "Never run"
-  end
-
-  teardown_all do
-    raise "Never run"
-  end
 end

lib/ex_unit/test/ex_unit/capture_io_test.exs

@@ -1,41 +1,32 @@
 Code.require_file "../test_helper.exs", __DIR__
 
-defmodule ExUnit.CaptureIOTest.Value do
-  def binary, do: "a"
-end
-
-alias ExUnit.CaptureIOTest.Value
+defmodule ExUnit.CaptureIOTest do
+  use ExUnit.Case
 
-defmodule ExUnit.CaptureIOTest.GetUntil do
-  def until_new_line(_, :eof, _) do
-    {:done, :eof, []}
-  end
+  defmodule GetUntil do
+    def until_new_line(_, :eof, _) do
+      {:done, :eof, []}
+    end
 
-  def until_new_line(this_far, chars, stop_char) do
-    case Enum.split_while(chars, fn(c) -> c != stop_char end) do
-      {l, []} ->
-        {:more, this_far ++ l}
-      {l, [stop_char|rest]} ->
-        {:done, this_far ++ l ++ [stop_char], rest}
+    def until_new_line(this_far, chars, stop_char) do
+      case Enum.split_while(chars, fn(c) -> c != stop_char end) do
+        {l, []} ->
+          {:more, this_far ++ l}
+        {l, [stop_char|rest]} ->
+          {:done, this_far ++ l ++ [stop_char], rest}
+      end
     end
-  end
 
-  def get_line(device \\ Process.group_leader) do
-    send device, {:io_request, self, device, {:get_until, :unicode, "", __MODULE__, :until_new_line, [?\n]}}
-    receive do
-      {:io_reply, _, data} -> data
+    def get_line(device \\ Process.group_leader) do
+      send device, {:io_request, self, device, {:get_until, :unicode, "", __MODULE__, :until_new_line, [?\n]}}
+      receive do
+        {:io_reply, _, data} -> data
+      end
     end
   end
-end
-
-alias ExUnit.CaptureIOTest.GetUntil
-
-defmodule ExUnit.CaptureIOTest do
-  use ExUnit.Case
-
-  doctest ExUnit.CaptureIO, import: true
 
   import ExUnit.CaptureIO
+  doctest ExUnit.CaptureIO, import: true
 
   test "with no output" do
     assert capture_io(fn ->
@@ -52,10 +43,6 @@ defmodule ExUnit.CaptureIOTest do
       :io.put_chars("b")
     end) == "ab"
 
-    assert capture_io(fn ->
-      send_and_receive_io({:put_chars, :unicode, Value, :binary, []})
-    end) == "a"
-
     assert capture_io(fn ->
       :io.put_chars("josé")
     end) == "josé"

lib/ex_unit/test/ex_unit/case_template_test.exs

@@ -21,16 +21,6 @@ defmodule ExUnit.SampleCase do
     assert context[:context] == :setup_all
     {:ok, [context: :setup, setup: 1]}
   end
-
-  teardown context do
-    assert context[:context] == :setup
-    :ok
-  end
-
-  teardown_all context do
-    assert context[:context] == :setup_all
-    :ok
-  end
 end
 
 defmodule ExUnit.NestedCase do

lib/ex_unit/test/ex_unit/doc_test_test.exs

@@ -1,6 +1,6 @@
 Code.require_file "../test_helper.exs", __DIR__
 
-import PathHelpers
+import ExUnit.TestHelpers
 
 defmodule ExUnit.DocTestTest.GoodModule do
   @doc """