add support for `rebar3 eunit --file=...'

src/rebar_prv_eunit.erl

@@ -109,7 +109,7 @@ prepare_tests(State) ->
     {RawOpts, _} = rebar_state:command_parsed_args(State),
     ok = maybe_cover_compile(State, RawOpts),
     ProjectApps = project_apps(State),
-    resolve_apps(ProjectApps, RawOpts).
+    resolve_tests(ProjectApps, RawOpts).
 
 maybe_cover_compile(State, Opts) ->
     State1 = case proplists:get_value(cover, Opts, false) of
@@ -118,6 +118,26 @@ maybe_cover_compile(State, Opts) ->
     end,
     rebar_prv_cover:maybe_cover_compile(State1).
 
+resolve_tests(ProjectApps, RawOpts) ->
+    case proplists:get_value(file, RawOpts) of
+        undefined -> resolve_apps(ProjectApps, RawOpts);
+        Files     -> resolve_files(ProjectApps, Files, RawOpts)
+    end.
+
+resolve_files(ProjectApps, Files, RawOpts) ->
+    case {proplists:get_value(app, RawOpts), proplists:get_value(suite, RawOpts)} of
+        {undefined, undefined} -> resolve_files(Files, []);
+        _                      ->
+        case resolve_apps(ProjectApps, RawOpts) of
+            {ok, TestSet} -> resolve_files(Files, TestSet);
+            Error         -> Error
+        end
+    end.
+
+resolve_files(Files, TestSet) ->
+    FileNames = string:tokens(Files, [$,]),
+    {ok, TestSet ++ set_files(FileNames, [])}.
+
 resolve_apps(ProjectApps, RawOpts) ->
     case proplists:get_value(app, RawOpts) of
         undefined -> resolve_suites(ProjectApps, RawOpts);
@@ -217,6 +237,10 @@ set_suites([], Acc) -> lists:reverse(Acc);
 set_suites([Suite|Rest], Acc) ->
     set_suites(Rest, [{module, list_to_atom(Suite)}|Acc]).
 
+set_files([], Acc) -> lists:reverse(Acc);
+set_files([File|Rest], Acc) ->
+    set_files(Rest, [{file, File}|Acc]).
+
 resolve_eunit_opts(State) ->
     {Opts, _} = rebar_state:command_parsed_args(State),
     EUnitOpts = rebar_state:get(State, eunit_opts, []),
@@ -241,10 +265,12 @@ handle_results({error, Reason}) ->
 eunit_opts(_State) ->
     [{app, undefined, "app", string, help(app)},
      {cover, $c, "cover", boolean, help(cover)},
+     {file, $f, "file", string, help(file)},
      {suite, undefined, "suite", string, help(suite)},
      {verbose, $v, "verbose", boolean, help(verbose)}].
 
-help(app)    -> "List of application test suites to run";
+help(app)     -> "Comma seperated list of application test suites to run";
 help(cover)   -> "Generate cover data";
-help(suite)   -> "List of test suites to run";
+help(file)    -> "Comma seperated list of modules to run";
+help(suite)   -> "Comma seperated list of test suites to run";
 help(verbose) -> "Verbose output".

test/rebar_eunit_SUITE.erl

@@ -18,7 +18,10 @@
          test_single_suite_flag/1,
          test_suite_in_app_flag/1,
          test_suite_in_wrong_app_flag/1,
-         test_nonexistent_suite_flag/1]).
+         test_nonexistent_suite_flag/1,
+         test_single_file_flag/1,
+         test_multiple_file_flag/1,
+         test_nonexistent_file_flag/1]).
 
 -include_lib("common_test/include/ct.hrl").
 -include_lib("eunit/include/eunit.hrl").
@@ -42,7 +45,8 @@ all() ->
      test_basic_defines, test_multi_defines,
      test_single_app_flag, test_multiple_app_flag, test_nonexistent_app_flag,
      test_single_suite_flag, test_suite_in_app_flag,
-     test_suite_in_wrong_app_flag, test_nonexistent_suite_flag].
+     test_suite_in_wrong_app_flag, test_nonexistent_suite_flag,
+     test_single_file_flag, test_multiple_file_flag, test_nonexistent_file_flag].
 
 test_basic_app(Config) ->
     AppDir = ?config(apps, Config),
@@ -406,3 +410,55 @@ test_nonexistent_suite_flag(Config) ->
                                                          return),
 
     Error = {error_running_tests, "Module `not_a_real_module' not found in applications."}.
+
+test_single_file_flag(Config) ->
+    AppDir = ?config(apps, Config),
+
+    Name = rebar_test_utils:create_random_name("single_file_flag_app_"),
+    Vsn = rebar_test_utils:create_random_vsn(),
+    rebar_test_utils:create_eunit_app(AppDir, Name, Vsn, [kernel, stdlib]),
+
+    RebarConfig = [{erl_opts, [{d, some_define}]}],
+    rebar_test_utils:run_and_check(Config,
+                                   RebarConfig,
+                                   ["eunit", "--file=not_a_real_src_" ++ Name ++ "_tests.beam"],
+                                   {ok, [{app, Name}]}),
+
+    File = list_to_atom("not_a_real_src_" ++ Name ++ "_tests"),
+    {module, File} = code:ensure_loaded(File).
+
+test_multiple_file_flag(Config) ->
+    AppDir = ?config(apps, Config),
+
+    Name = rebar_test_utils:create_random_name("multiple_file_flag_app_"),
+    Vsn = rebar_test_utils:create_random_vsn(),
+    rebar_test_utils:create_eunit_app(AppDir, Name, Vsn, [kernel, stdlib]),
+
+    RebarConfig = [{erl_opts, [{d, some_define}]}],
+    rebar_test_utils:run_and_check(Config,
+                                   RebarConfig,
+                                   ["eunit", "--file=not_a_real_src_" ++ Name ++ "_tests.beam,not_a_real_src_" ++ Name ++ ".beam"],
+                                   {ok, [{app, Name}]}),
+
+    File1 = list_to_atom("not_a_real_src_" ++ Name ++ "_tests"),
+    {module, File1} = code:ensure_loaded(File1),
+
+    File2 = list_to_atom("not_a_real_src_" ++ Name),
+    {module, File2} = code:ensure_loaded(File2).
+
+test_nonexistent_file_flag(Config) ->
+    AppDir = ?config(apps, Config),
+
+    Name = rebar_test_utils:create_random_name("nonexistent_file_flag_app_"),
+    Vsn = rebar_test_utils:create_random_vsn(),
+    rebar_test_utils:create_eunit_app(AppDir,
+                                      Name,
+                                      Vsn,
+                                      [kernel, stdlib]),
+
+    RebarConfig = [{erl_opts, [{d, some_define}]}],
+    {error, {rebar_prv_eunit, _Error}} = rebar_test_utils:run_and_check(Config,
+                                                         RebarConfig,
+                                                         ["eunit", "--file=" ++ filename:join(["some_path", "not_a_real_file.erl"])],
+                                                         return).
+