Erlang Programming/Unit Testing with eunit

Installing eunit

This section will show you how to install eunit on different operating systems. Once you have installed eunit its use is fairly consistent across the different operating systems.

ubuntu

Get source with:

    svn co http://svn.process-one.net/contribs/trunk/eunit eunit

Compile code with:

    .../eunit$ make

Copy to /usr/lib/erlang/lib

Test the Installation

To test that everything is installed ok before writing any tests create a file test01.erl with the following contents:

  -module(test01).
  -compile(export_all).
  -include_lib("eunit/include/eunit.hrl").

Compile this file as follows:

  $ erl
  > c(test01).
  {ok,test01}

If you get the result {ok,test01} then you've installed eunit correctly.

Using eunit

We'll start by writing a passing test and a failing test. In the file you created to check the installation add the following:

passing_test() -> ?assert(true).

failing_test() -> ?assert(false).

Run the tests as follows.

Eshell V5.5.5  (abort with ^G)
1> c(test01).
{ok,test01}
2> test01:test().
test01:failing_test...*failed*
::error:{assertion_failed,[{module,test01},
                         {line,29},
                         {expression,"false"},
                         {expected,true},
                         {value,false}]}
  in function test01:'-failing_test/0-fun-0-'/0

=======================================================
  Failed: 1.  Aborted: 0.  Skipped: 0.  Succeeded: 3.
error
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