Make projectile--find-matching-test Use src-dir/test-dir Properties

[LaurenceWarne]

Hi! This PR is in response to a discussion in #1650 (comment), basically it's a fix for the src-dir and test-dir properties being prematurely circumvented if they are set to strings when switching from/to test/impl files. Essentially the function for finding a test/impl file using src-dir and test-dir (set as strings) was called in projectile--find-matching-test, but a fallback already existed in projectile-find-implementation-or-test which was being used in preference.

This PR hopes to fix and simplify the above by making impl/test switching wholly contained in projectile--find-matching-file/projectile--find-matching-test.

I've also updated the doc tweaking the src-dir/test-dir as a function example since I think that situation is better handled by setting src-dir/test-dir to strings (as pointed out by the issue author in the link).

Thanks!

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Thanks!

[LaurenceWarne]

Basically the main change (and in projectile--find-matching-file).

[LaurenceWarne]

Test for the example in #1650. This would fail before this change, since

projectile/projectile.el

Line 3574 in 2bb7ec2

(when-let ((predicate (projectile--impl-to-test-predicate impl-file)))

would take precedence over using the src-dir/test-dir properties.

[LaurenceWarne]

Ah earlier Emacs version compat caught me out again 🤦, back to 🔨

Edit: Looks good now, I can squash the commits also if you like.

[bbatsov]

Great PR! Thanks! 🙇‍♂️

[LaurenceWarne]

Thanks!

[dklimov-allstreet]

it looks like something is broken

(let* ((error-msg (format
                   "No matching test file found for project type `%s'"
                   (projectile-project-type)))
       (test-file (or (projectile-find-matching-test file-name)
                      (error error-msg))) ; <- bam!
       (expanded-test-file (projectile-expand-root test-file)))
  (cond ((file-exists-p expanded-test-file) expanded-test-file) ; we never get here if there's no test file 
        (projectile-create-missing-test-files 
         (projectile--create-directories-for expanded-test-file)
         expanded-test-file)
        (t (progn (error error-msg)))))

ever tried to test the code with projectile-create-missing-test-files enabled?

CC @bbatsov

[bbatsov]

@dklimov-allstreet feel free to open a new issue or just send a PR addressing this. Looking at the problem the fix should be relatively simple.