Erlang - EUnitで単体テスト

足し算関数をeunitでテスト
eunitは実行するとモジュール内のtest関数を探して試験してくれます

main.erl

-module(main).
-author("haminiku").

%% API
-export([add/2]).
add(A, B) -> A + B.

tests.erl

-module(tests).
-include_lib("eunit/include/eunit.hrl").
-author("haminiku").

%% API
-export([test/0]).

%% テスト実行
%% erl -noshell -pa ebin -eval "eunit:test(test_module, [verbose])" -s init stop

test() ->
  add_test(),
  assert_test().

add_test() ->
  4 = main:add(2, 2),
  5 = main:add(2, 2).

assert_test() ->
  ?assertEqual(4, main:add(2, 2)),
  ?assertEqual(5, main:add(2, 2)).

%% 関数名にtestが無いので実行されない
sample() -> ?assertEqual(1000, main:add(2, 2)).

# コンパイル
>>>erlc ./tests.erl 

# テスト実行
>>>erl -noshell -pa ebin -eval "eunit:test(tests, [verbose])" -s init stop
======================== EUnit ========================
module 'tests'
  tests: add_test...*failed*
in function tests:add_test/0 (tests.erl, line 17)
**error:{badmatch,4}
  output:<<"">>

  tests: assert_test...*failed*
in function tests:'-assert_test/0-fun-1-'/1 (tests.erl, line 21)
**error:{assertEqual,[{module,tests},
              {line,21},
              {expression,"main : add ( 2 , 2 )"},
              {expected,5},
              {value,4}]}
  output:<<"">>

  [done in 0.009 s]
=======================================================
  Failed: 2.  Skipped: 0.  Passed: 0.