elixir: Fix mix test $ZED_SYMBOL task

[feliperenan]

$ZED_SYMBOL doesn't really work here once that will try to do something like this:

mix test MyModule.MyModuleTest

instead of using the path of the file:

mix test test/my_module/my_module_test.exs

Release Notes:

• Fix mix test $ZED_SYMBOL to use ZED_RELATIVE_FILE instead
• Use ZED_RELATIVE_FILE instead of ZED_FILE to improve mix tasks results on Elixir umbrella projects

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[feliperenan]

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[feliperenan]

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[feliperenan]

I wonder if we could have another variable, something like ZED_RELATIVE_FILE_PATH. The reason is that when running this task within umbrella apps, that will output test runs for all projects even though they are skipped. For instance:

❯ mix test /Users/feliperenan/source/my_umbrella_app/apps/my_app/test/my_app_web/controllers/my_controller_test.exs
==> my_app
......

Finished in 1.9 seconds (1.9s async, 0.00s sync)
6 tests, 0 failures

Randomized with seed 45266
==> another_app_within_umbrella_app


Finished in 0.00 seconds (0.00s async, 0.00s sync)
0 failures

While, if we use the relative path, it would be:

❯ mix test apps/my_app/test/my_app_web/controllers/my_controller_test.exs
==> my_app
......

Finished in 1.3 seconds (1.3s async, 0.00s sync)
6 tests, 0 failures

Randomized with seed 507991

[baldwindavid]

This must have gotten broken during the recent move of elixir support into an extension. I already had my own elixir tasks so didn't notice. As you mention, it would be nice to have something like $ZED_RELATIVE_PATH. A relative path is also necessary for using the browse functionality of the Github CLI (https://cli.github.com/manual/gh_browse).

[osiewicz]

I've added ZED_RELATIVE_FILE in #12245

[feliperenan]

Thank you @osiewicz. I just tested and it works like a charm. Just updated this PR to use ZED_RELATIVE_FILE as well.