What should be first, `Test.AppName` or `AppName.Test` for test modules?

If we are to include the label Test Anywhere in a test module name like

  • MyApp.Test.MyTestFile or
  • MyAppWeb.Test.MyTestFile,

which is the default, and since the test files are typically located under the test/ root level folder should we not begin all module names with Test?

This would mean:

  • Test.MyApp.MyTestFile and
  • Test.MyAppWeb.MyTestfile

Is the main argument for putting everything with app name first just to namespace all the test modules?

It is inconsistent to not follow the directory structure convention while also including the .Test. text in the middle a module name. The tests can already be identified by the ...Test ad the end of the file name.


If You use to_string, You will see the real nature of module’s name.
This is one of mine…

to_string Pr3f.Application 

There is no correspondance with the name You give and related file system. It is very flexible and You could give any name, in any directory, that would be just fine. Convention is to do what You prefer :slight_smile:

But for test, convention is to not use Test as a directory, but as MyApp/MyFileTest. And don’t forget they are just scripts… as they have exs extension. They are not compiled.

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As far as I remember, the filename has to match the glob *_test.exs, while the module names need to end in Test, so placing it anywhere else would be redundant.

The way ex unit discovers the tests answers your question.


@NobbZ, yes, *_test.exs is the test file matching pattern.
I agree that file suffixes are enough. Module names matching source file names with the Test module name suffix are specific enough. The question in my mind now becomes where to locate those test files.

@kokolegorille good point, I hadn’t thought of that. Are you putting test files in the same directory as your source modules? I’ve seen that in other language ecosystems and it seems to be handy at times though hard on the eyes if a directory grows much. An argument could be made that a module should likely be split if the directory becomes too full.

I was not very explicit, I follow the convention to put test files in test directory.

What I meant is I don’t use Test inside the test module name, but as a suffix.

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