Fix warnings during suite

Author: josevalim

lib/elixir/test/elixir/inspect_test.exs

@@ -591,7 +591,7 @@ defmodule Inspect.MapTest do
 
     {my_argument_error, stacktrace} =
       try do
-        Atom.to_string(failing.name)
+        atom_to_string(failing.name)
       rescue
         e ->
           {e, __STACKTRACE__}
@@ -610,6 +610,10 @@ defmodule Inspect.MapTest do
     assert inspected =~ message
   end
 
+  defp atom_to_string(atom) do
+    Atom.to_string(atom)
+  end
+
   test "exception" do
     assert inspect(%RuntimeError{message: "runtime error"}) ==
              "%RuntimeError{message: \"runtime error\"}"

lib/elixir/test/elixir/kernel/diagnostics_test.exs

@@ -5,9 +5,10 @@ defmodule Kernel.DiagnosticsTest do
 
   import ExUnit.CaptureIO
 
-  setup do
+  setup_all do
+    previous = Application.get_env(:elixir, :ansi_enabled, false)
     Application.put_env(:elixir, :ansi_enabled, false)
-    on_exit(fn -> Application.put_env(:elixir, :ansi_enabled, true) end)
+    on_exit(fn -> Application.put_env(:elixir, :ansi_enabled, previous) end)
   end
 
   describe "mismatched delimiter" do

lib/elixir/test/elixir/test_helper.exs

@@ -4,6 +4,7 @@ File.rm_rf!(path)
 File.mkdir_p!(path)
 Code.prepend_path(path)
 
+Application.put_env(:elixir, :ansi_enabled, true)
 Code.compiler_options(debug_info: true)
 
 defmodule PathHelpers do

lib/elixir/test/elixir/tuple_test.exs

@@ -49,13 +49,6 @@ defmodule TupleTest do
     assert mod.insert_at({:bar, :baz}, 0, :foo) == {:foo, :bar, :baz}
   end
 
-  test "append/2" do
-    assert Tuple.append({:foo, :bar}, :baz) == {:foo, :bar, :baz}
-
-    mod = Tuple
-    assert mod.append({:foo, :bar}, :baz) == {:foo, :bar, :baz}
-  end
-
   test "delete_at/2" do
     assert Tuple.delete_at({:foo, :bar, :baz}, 0) == {:bar, :baz}
 

lib/ex_unit/test/ex_unit/formatter_test.exs

@@ -514,13 +514,13 @@ defmodule ExUnit.FormatterTest do
   end
 
   test "inspect failure" do
-    failure = [{:error, catch_assertion(assert :will_fail == %BadInspect{}), []}]
+    failure = [{:error, catch_assertion(assert :will_fail == struct!(BadInspect)), []}]
 
     assert format_test_failure(test(), failure, 1, 80, &formatter/2) =~ ~s'''
              1) world (Hello)
                 test/ex_unit/formatter_test.exs:1
                 Assertion with == failed
-                code:  assert :will_fail == %BadInspect{}
+                code:  assert :will_fail == struct!(BadInspect)
                 left:  :will_fail
                 right: #Inspect.Error<
              got FunctionClauseError with message: