Running ExUnit tests from iex shell

Questions / Help
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1

Hello everyone,

I’m trying to run ExUnit tests from the shell, and I almost got it working:

iex(2)> ExUnit.start(autorun: false)                                                                            
:ok
iex(3)> test_file = "test/sample_test.exs"
"test/sample_test.exs"
iex(4)> Mix.Compilers.Test.require_and_run([test_file], ["test"], formatters: [ExUnit.CLIFormatter])

........

Finished in 3.6 seconds
8 tests, 0 failures
{:ok, %{excluded: 0, failures: 0, skipped: 0, total: 8}}

So far so good, but the second run of Mix.Compilers.Test.require_and_run/3 doesn’t seem to do anything:

iex(5)> Mix.Compilers.Test.require_and_run([test_file], ["test"], formatters: [ExUnit.CLIFormatter])

Finished in 0.00 seconds
0 failures

{:ok, %{excluded: 0, failures: 0, skipped: 0, total: 0}}

It looks like the test compiler caches the test results. If that’s the case, can it be forced to invalidate it and run the tests from scratch again?

2

Wild guess here, but I think require_and_run might check if all the files are required, and then chain it with a literal && - so if the files are already required, it might return false and the second part would not be executed.

Like I said, idk, but it makes sense to me.

EDIT: Maybe the second time just run .run? Another wild guess.

EDIT2: and just because I am curious, why do you need this?

3

Did you mean ExUnit.run ? Unfortunately, it didn’t help.
There are currently 2 reasons as to why I want to do this:

  1. to be able to pass the results of the tests, for instance, show the tests running on a web page;
  2. to be able to debug the unit tests with tracing tools, like Rexbug/redbug etc.
4

Unfortunately I don’ t really know what you are talking about - but it sounds like a CI Server.

I like to actually be in charge of when to deploy updates or upgrades (which is something a UI server should consider.)

Kind of weird that nobody has implemented anything yet, but I guess you are on your own for now.

5

Interesting idea! Mix tasks don’t re-execute by default. Try running Mix.Task.clear/0 before require_and_run (docs: https://hexdocs.pm/mix/Mix.Task.html#clear/0)

6

Thanks!
Unfortunately, no luck with Mix.Task.clear/0.

7

I wanted to do this because of the apps I’m working in at the moment has a long startup time, making TDD painful. Someone pointed me to a solution based on TestIex — Easier Test Driven Development in Elixir | by Daniel Olshansky | Medium and it works like treat.

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8

basically you have to load it again to rerun the test

Code.load_file(test_file)

or even better compile_file, since load_file is depricated

Code.compile_file(test_file")

then you can rerun

Mix.Compilers.Test.require_and_run([test_file], ["test"], formatters: [ExUnit.CLIFormatter])
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