macros are ignored

[sobolevn]

Does it supposed to be this way?

mix.exs:

defp deps do
    [
       ...
      {:excoveralls, "~> 0.5", only: :test}
    ]
  end

Result:

$ mix coveralls.html
.............

Finished in 0.1 seconds (0.1s on load, 0.02s on tests)
13 tests, 0 failures

Randomized with seed 989620
----------------
COV    FILE                                        LINES RELEVANT   MISSED
  0.0% lib/ecto_autoslug_field.ex                      2        0        0
100.0% lib/ecto_autoslug_field/slug.ex                35        2        0
  0.0% lib/ecto_autoslug_field/slug_generator.e       48        0        0
  0.0% lib/ecto_autoslug_field/type.ex                14        0        0
[TOTAL] 100.0%
----------------
Generating report...

[parroty]

Thanks for the report. It's kind of limitation around it's based on erlang's cover module and elixir's macro precomipling is not reflected well (haven't been able to find good workaround).

[nathany]

Is this related to coverage sometimes missing on all or part of the with macro in Elixir and the schema macro in Ecto?

[ctrlShiftBryan]

@nathany yes, it appears so since elixir implements those using macros.

[idyll]

Have the changes in Elixir 1.5 helped with this or are we still unable to see coverage on macros?

[tim2CF]

it seems macros still have test coverage = 0

[BlueHotDog]

Hey, any idea if this is fixable? @parroty

[josevalim]

This should work fine, as long as the macros are invoked during your tests (not in test/support but in your test files, either within the test module or a test itself):

# lib/foo.ex
defmodule Foo do
  defmacro __using__(mod) do
    mod = Module.concat([mod])

    quote do
      import unquote(mod)
    end
  end
end

# test/foo_test.exs
defmodule FooTest do
  use ExUnit.Case

  test "greets the world" do
    defmodule FooTest do
      use Foo, "List"
      assert flatten([]) == []
    end
  end
end

Cover is not going to track any code before your tests start running (and that's where most macro expansion happens).