fix: fix incorect coverage reporting (fix #375)

[Demivan]

This reverts #584 - runtime coverage is not reporting functions that are not used as not covered.

Added manual soucemap adjustments because Vitest is prepending code to every file.

Fixes #375

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[mitchelvanbever]

Tested it agains a local branch but playing around with my test files did not result in different coverage and there is one line always uncovered no matter what test I write to accomodate for covering that line.

[Demivan]

@mitchelvanbever can you share a repo?

[mitchelvanbever]

@mitchelvanbever can you share a repo?

Just tried with the example folder react-testing-lib and it shows the same behaviour. The other node project is private, but I can try it with another public repo I have

[Demivan]

This change fixed coverage for coverage-test test. And tested coverage with fluent-vue - it is correct now.

[Demivan]

Just tried with the example folder react-testing-lib and it shows the same behaviour. The other node project is private, but I can try it with another public repo I have

Tested with react-testing-lib example after skipping error test, error branch is now not covered:

[mitchelvanbever]

Just tried with the example folder react-testing-lib and it shows the same behaviour. The other node project is private, but I can try it with another public repo I have

Tested with react-testing-lib example after skipping error test, error branch is now not covered:

I feel really stupid 🙈 I think I just didn't configure the coverage properly yesterday when trying it out. I was too excited about it 😬 I tried again on the example dir, with the proper configuration and I can confirm to have the same result as you show.

[antfu]

Epic, awesome work @Demivan!

[antfu]

Later we should calculate this number based on the length of the arguments, but I am fine to have the magic number for now.

[cexbrayat]

FYI, the introduction of takeCoverage makes it incompatible with node < v14.18
As Stackblitz uses v14.16, the runnable examples can no longer launch the code coverage in WebContainers:

❯ npm run coverage
$ vitest run --coverage
(node:56) UnhandledPromiseRejectionWarning: file:///home/projects/vitest-dev-vitest-ilb2yu/node_modules/vitest/dist/create-a1bc541a.js:13
import { takeCoverage } from 'v8';
         ^^^^^^^^^^^^

[Demivan]

@cexbrayat Yeah, we have issue about this already #670. Not sure what is the best solution. Without takeCoverage coverage will be incomplete.