How to setup tests with the appropriate code using rebar3? - automated-tests

Question

I have created a simple application via rebar3 templates such as:
apps/myapp/app/myapp_app.erl
-module(myapp_app).
-behaviour(application).
-export([start/2, stop/1]).
start(_StartType, _Params) ->
ok.
stop(_State) ->
ok.
I have written a test for that:
apps/myapp/test/myapp_test.erl
-module(myapp_test).
-include_lib("eunit/include/eunit.hrl").
simple_test() ->
myapp_app:start(ok, 42).
Sadly, when I launch the test, it seems that the link is not done between the two files:
$ rebar3 eunit
===> Verifying dependencies...
===> Compiling shoreline
===> Performing EUnit tests...
F
Failures:
1) myapp_test:simple_test/0
Failure/Error: {error,undef,
[{myapp_app,start,"*",[]},
{myapp_test,simple_test,0,
[{file,
"/.../apps/myapp/test/myapp_test.erl"},
{line,8}]},
{myapp_test,simple_test,0,[]}]}
Output:
Finished in 0.074 seconds
1 tests, 1 failures
===> Error running tests
Is there something to add in rebar.config?

Answer 1

If you have .erl files in a custom directory other than 'src', then you need to add it to the code path.
You can do it using rebar3 by modifying erl_opts section in 'rebar.config' as below.
{erl_opts, [debug_info, {src_dirs, ["src", "app"]}]}.
Hope this can work for you.

Answer 2

rebar3 does not find your .erl files if you have been under /app I moved them to /src.
➜ myapp rebar3 eunit
===> Verifying dependencies...
===> Compiling myapp
===> Performing EUnit tests...
.
Finished in 0.081 seconds
1 tests, 0 failures
➜ myapp ls
LICENSE README.md _build rebar.config src test
➜ myapp mv src app
➜ myapp rebar3 eunit
===> Verifying dependencies...
===> Performing EUnit tests...
F
Failures:
1) myapp_test:simple_test/0: module 'myapp_test'
Failure/Error: {error,undef,
[{myapp_app,start,[ok,42],[]},
{myapp_test,simple_test,0,[]}]}
Output:
Finished in 0.036 seconds
1 tests, 1 failures
===> Error running tests
undef means could not be found when evaluating the call at runtime. 2 To help see what rebar3 is doing I can highly recommend debug, DEBUG=1.