Support :test_elixirc_options in mix test

And skip debug and docs chunks by default.

Closes elixir-lang#11755.

Author: josevalim

lib/mix/lib/mix/compilers/test.ex

@@ -22,7 +22,7 @@ defmodule Mix.Compilers.Test do
   It expects all of the test patterns, the test files that were matched for the
   test patterns, the test paths, and the opts from the test task.
   """
-  def require_and_run(matched_test_files, test_paths, opts) do
+  def require_and_run(matched_test_files, test_paths, elixirc_opts, opts) do
     stale = opts[:stale]
 
     {test_files, stale_manifest_pid, parallel_require_callbacks} =
@@ -39,7 +39,7 @@ defmodule Mix.Compilers.Test do
         :noop
 
       Keyword.get(opts, :profile_require) == "time" ->
-        Kernel.ParallelCompiler.require(test_files, profile: :time)
+        require(test_files, [profile: :time], elixirc_opts)
         :noop
 
       true ->
@@ -48,7 +48,7 @@ defmodule Mix.Compilers.Test do
 
         try do
           failed? =
-            case Kernel.ParallelCompiler.require(test_files, parallel_require_callbacks) do
+            case require(test_files, parallel_require_callbacks, elixirc_opts) do
               {:ok, _, [_ | _]} when warnings_as_errors? -> true
               {:ok, _, _} -> false
               {:error, _, _} -> exit({:shutdown, 1})
@@ -81,6 +81,17 @@ defmodule Mix.Compilers.Test do
     end
   end
 
+  defp require(files, require_opts, elixirc_opts) do
+    elixirc_opts = Keyword.merge([docs: false, debug_info: false], elixirc_opts)
+    previous_opts = Code.compiler_options(elixirc_opts)
+
+    try do
+      Kernel.ParallelCompiler.require(files, require_opts)
+    after
+      Code.compiler_options(previous_opts)
+    end
+  end
+
   defp set_up_stale(matched_test_files, test_paths, opts) do
     manifest = manifest()
     modified = Mix.Utils.last_modified(manifest)

lib/mix/lib/mix/tasks/test.ex

@@ -190,6 +190,13 @@ defmodule Mix.Tasks.Test do
 
   These configurations can be set in the `def project` section of your `mix.exs`:
 
+    * `:test_coverage` - a set of options to be passed down to the coverage
+      mechanism. See the "Coverage" section for more information
+
+    * `:test_elixirc_options` - the compiler options to used when
+      loading/compiling test files. By default it disables the debug chunk
+      and docs chunk
+
     * `:test_paths` - list of paths containing test files. Defaults to
       `["test"]` if the `test` directory exists; otherwise, it defaults to `[]`.
       It is expected that all test paths contain a `test_helper.exs` file
@@ -199,9 +206,6 @@ defmodule Mix.Tasks.Test do
     * `:warn_test_pattern` - a pattern to match potentially misnamed test files
       and display a warning. Defaults to `*_test.ex`
 
-    * `:test_coverage` - a set of options to be passed down to the coverage
-      mechanism. See the "Coverage" section for more information
-
   ## Coloring
 
   Coloring is enabled by default on most Unix terminals. They are also
@@ -523,6 +527,7 @@ defmodule Mix.Tasks.Test do
     ExUnit.configure(merge_helper_opts(ex_unit_opts))
 
     # Finally parse, require and load the files
+    test_elixirc_options = project[:test_elixirc_options] || []
     test_files = parse_files(files, shell, test_paths)
     test_pattern = project[:test_pattern] || "*_test.exs"
     warn_test_pattern = project[:warn_test_pattern] || "*_test.ex"
@@ -535,7 +540,7 @@ defmodule Mix.Tasks.Test do
 
     display_warn_test_pattern(test_files, test_pattern, matched_test_files, warn_test_pattern)
 
-    case CT.require_and_run(matched_test_files, test_paths, opts) do
+    case CT.require_and_run(matched_test_files, test_paths, test_elixirc_options, opts) do
       {:ok, %{excluded: excluded, failures: failures, total: total}} ->
         Mix.shell(shell)
         cover && cover.()