feat(linter): Support --print-config feature of ESLint

[tonyganchev]

The change introduces a new option to the linter plugin schema: printConfig, accepting a file name for which the plugin to output its applicable ESLint configuration.

Current Behavior

There is no support for --print-config.

Expected Behavior

When --printConfig is passed on the command line as a parameter to nx lint ... or printConfig is specified in the project.json the linter will show the effective ESLint configuration applicable to the specified file and not proceed with linting the project. Operation would complete successfully.

Related Issue(s)

none

Fixes #

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Name	Status	Preview	Comments	Updated (UTC)
nx-dev	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Jul 29, 2023 5:17am

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✅ Successfully ran 8 targets

• linux nx affected --target=e2e --base=d1d06349e703d903ac47fb7adc7d250ce140d77e --head=dca8c39f775120f8669534df20f77ad14837f57f --parallel=1
• linux nx affected --target=test --base=d1d06349e703d903ac47fb7adc7d250ce140d77e --head=dca8c39f775120f8669534df20f77ad14837f57f --parallel=1
• linux nx affected --target=build --base=d1d06349e703d903ac47fb7adc7d250ce140d77e --head=dca8c39f775120f8669534df20f77ad14837f57f --parallel=3
• linux nx run-many -t check-imports check-commit check-lock-files check-codeowners documentation --parallel=1 --no-dte
• linux nx affected --target=lint --base=d1d06349e703d903ac47fb7adc7d250ce140d77e --head=dca8c39f775120f8669534df20f77ad14837f57f --parallel=3
• nx-cloud record -- nx format:check --base=d1d06349e703d903ac47fb7adc7d250ce140d77e --head=dca8c39f775120f8669534df20f77ad14837f57f
• linux nx documentation --no-dte
• macos nx affected -t e2e-macos --parallel=1 --base=d1d06349e703d903ac47fb7adc7d250ce140d77e --head=dca8c39f775120f8669534df20f77ad14837f57f

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[meeroslav]

Hi @tonyganchev,

Thank you for creating this PR.

The purpose of eslint executor is to enable us to control the linting and achieve nx features such as orchestration, task running, caching, affected graph, etc. We call eslint CLI directly when invoking the linting.

Printing out configuration doesn't need any of that and you can easily run it as npx eslint --print-config name-of-the-file.

Why would you need this as a parameter in the executor?

[tonyganchev]

Hi @tonyganchev,

Thank you for creating this PR.

The purpose of eslint executor is to enable us to control the linting and achieve nx features such as orchestration, task running, caching, affected graph, etc. We call eslint CLI directly when invoking the linting.

Printing out configuration doesn't need any of that and you can easily run it as npx eslint --print-config name-of-the-file.

Why would you need this as a parameter in the executor?

@meeroslav looking at the code I was under the impression that the nx plugin is invoking the ESLint API directly in resolveAndInstantiateESLint() of eslint-utils.ts.

In any case I have been hitting issues where running eslint on the command line yields different results from running nx lint e.g. some files don't seem to be selected in nx-orchestrated lint. I needed a way to determine if nx was modifying the ESLint configuration / ruleset or there was a different issue. Turns out the issue was incorrect file selection in the lint target definition in the project.json which I could only spot through manual inspection i.e. looked at the config and miraculously I spotted it :)

Providing access to all capabilities of the orchestrated tools should be critical in helping developers troubleshoot integration issues, learn the nx tooling and therefore trust it.

Best
Tony

[meeroslav]

Thank you, @tonyganchev, for clarifying that. It makes more sense now, why one would need this flag supported in our executor.

And yes, you are right; we use API, not CLI (that was a typo on my side, sorry for the confusion).

[meeroslav]

Can you also add an E2E test, please, to https://github.com/tonyganchev/nx/blob/topic/tonyganchev/linter-print-config/e2e/linter/src/linter.test.ts that would test this flag?

[tonyganchev]

Can you also add an E2E test, please, to https://github.com/tonyganchev/nx/blob/topic/tonyganchev/linter-print-config/e2e/linter/src/linter.test.ts that would test this flag?

Certainly. The latest version now includes a test for this.

[meeroslav]

Looks good to me. Thanks!

[github-actions]

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