Merge pull request #150 from iamvery/format-match-failures

Format match failures

lib/display/colours.ex

@@ -27,8 +27,7 @@ end
 
 defmodule Display.Uncoloured do
   def red(str), do: str
-
   def cyan(str), do: str
-
   def green(str), do: str
+  def yellow(str), do: str
 end

lib/display/failure.ex

@@ -26,6 +26,12 @@ defmodule Display.Failure do
   defp format_inequality(message, %{left: @no_value, right: @no_value}) do
     message
   end
+  defp format_inequality(message, %{left: @no_value, right: match_value}) do
+    """
+    #{message}
+    value does not match: #{match_value |> inspect |> Paint.yellow}
+    """
+  end
   defp format_inequality(message, %{left: left, right: right}) do
     """
     #{message}

test/display/failure_test.exs

@@ -14,6 +14,29 @@ defmodule FailureTests do
     assert Failure.format_failure(error) == "Assertion failed in some_file.ex:42\nhola\n"
   end
 
+  test "equality failure" do
+    error = error(%ExUnit.AssertionError{expr: quote(do: :lol == :wat), left: :lol, right: :wat})
+
+    assert Failure.format_failure(error) == """
+                                            Assertion failed in some_file.ex:42
+                                            :lol == :wat
+
+                                            left:  :lol
+                                            right: :wat
+                                            """
+  end
+
+  test "match failure" do
+    error = error(%ExUnit.AssertionError{expr: quote(do: match?(:lol,:wat)), right: :wat})
+
+    assert Failure.format_failure(error) == """
+                                            Assertion failed in some_file.ex:42
+                                            match?(:lol, :wat)
+
+                                            value does not match: :wat
+                                            """
+  end
+
   defp error(error) do
     %{
       error: error,