Show clear indicator in the output when `.only()` is used

[sindresorhus]

It's easy to forget and end up not running the rest of the tests before pushing changes.

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Similar to #1134.

[tjbenton]

This happened to me yesterday

[sindresorhus]

@tjbenton I would recommend using our ESLint plugin, which would have caught that and many other things.

[ThomasBem]

I have made a PR that fixes #1134 in -> #1160 and since this is kind of similar I would like to take a stab at this too.

[sindresorhus]

@ThomasBem Go for it! 😄

[ThomasBem]

After looking at the code its really easy to get this to print out a warning similar to what was done for the #1134 issue in the #1160 PR.

I was thinking about changing the logic around counting tests when in .only / exclusive mode. I did some quick testing and I could make it at least count all the tests in files that does NOT contain any .only tests.

This would look something like this:

If all test files have at least one .only test in them, it logs this:
''There are tests with the .only() modifier in use. All other tests have been skipped''

If there are additional test files that do not contain any .only tests, it logs this:
"There are tests with the .only() modifier in use. At least', remainingTests, 'tests were not run."

remainingTests would then be the number of tests in the files without exclusive tests in them.

Any thoughts around this?

[mightyiam]

Perhaps instead of
"There are tests with the .only() modifier in use"
be it
"The .only() modifier is used in some tests"

[ThomasBem]

I agree, that wording is much better.

Any thoughts regarding if there is any point to adding additional details around a number of tests skipped?