feat(eslint-plugin): [no-import-type-side-effects] add rule to warn against runtime side effects with verbatimModuleSyntax

[bradzacher]

PR Checklist

• Addresses an existing open issue: fixes Rule proposal: warn against import declarations with no value specifiers and only inline type specifiers #6382
• That issue was marked as accepting prs
• Steps in CONTRIBUTING.md were taken

Overview

Pretty straight-forward rule to implement with a fixer.

[typescript-eslint]

Thanks for the PR, @bradzacher!

typescript-eslint is a 100% community driven project, and we are incredibly grateful that you are contributing to that community.

The core maintainers work on this in their personal time, so please understand that it may not be possible for them to review your work immediately.

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[codecov]

Codecov Report

Merging #6394 (da7b02f) into main (202d9fb) will increase coverage by 0.15%.
The diff coverage is 91.66%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6394      +/-   ##
==========================================
+ Coverage   91.37%   91.52%   +0.15%     
==========================================
  Files         368      371       +3     
  Lines       12596    12649      +53     
  Branches     3709     3714       +5     
==========================================
+ Hits        11509    11577      +68     
+ Misses        772      755      -17     
- Partials      315      317       +2     

Flag	Coverage Δ
unittest	91.52% <91.66%> (+0.15%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
packages/utils/src/ts-eslint/SourceCode.ts	50.00% <ø> (ø)
packages/utils/src/ast-utils/predicates.ts	51.02% <50.00%> (-0.10%)	⬇️
...eslint-plugin/src/rules/consistent-type-imports.ts	94.50% <100.00%> (-0.04%)	⬇️
...nt-plugin/src/rules/no-import-type-side-effects.ts	100.00% <100.00%> (ø)
...ges/typescript-estree/src/create-program/shared.ts	80.43% <0.00%> (-2.90%)	⬇️
...s/eslint-plugin/src/rules/prefer-optional-chain.ts	97.50% <0.00%> (-1.18%)	⬇️
packages/eslint-plugin/src/util/misc.ts	97.01% <0.00%> (ø)
packages/eslint-plugin/src/rules/prefer-for-of.ts	91.42% <0.00%> (ø)
...ges/scope-manager/src/referencer/PatternVisitor.ts	68.29% <0.00%> (ø)
...es/eslint-plugin/src/rules/prefer-function-type.ts	97.18% <0.00%> (ø)
... and 7 more

[JoshuaKGoldberg]

Great! Nothing blocking from me, only suggestions (and most of them teeny nitpicks). ✨

[bradzacher]

cc @DanielRosenwasser / @andrewbranch
This rule will be released next Monday.

[andrewbranch]

Awesome, thank you!

[thenbe]

Hi. Just wondering if the following behavior in this new rule is intentional or working as intended. Currently, it's flagging all side-effect imports. Meanwhile, the docs describe the rule as:

Enforce the use of top-level import type qualifier when an import only has specifiers with inline type qualifiers

It doesn't say anything about imports that have neither top-level nor inline type specifiers, such as side-effect imports.

If this is intentional, and this rule does act on side-effect imports, should we mention that in the docs? Else, would it make sense for this rule to have an option to not act on side-effect imports? Or is explicitly ignoring this rule for every instance the recommended approach?

Repro: https://stackblitz.com/edit/repro-side-effect-lint?file=README.md

[JoshuaKGoldberg]

@ambiguous48 please file an issue using one of our issue templates (I'm guessing 🐛 Report a Bug With a Rule). That'll help us address it more quickly, spotlight any missing info, and help us track which version(s) bugs & fixes appear in. Thanks!

[JoshuaKGoldberg]

Ah, someone already did! #6431

Which is another point in favor of using the templates. They have useful links around searching for duplicate issues.

[bradzacher]

Yup - as per our contributing guide, comments on closed PRs are not the way to ask questions or report bugs.

https://typescript-eslint.io/contributing/issues#commenting

As Josh pointed out - this bug has already been reported.