[dynamic-import-chunkname] Disallow chunk name when eager mode is enabled

[amsardesai]

The dynamic-import-chunkname rule is useful for catching missing chunk names for imports, however much of our imports use webpackMode: "eager" to disable creating a separate chunk (i.e for lazy evaluation). Adding webpackChunkName anyway can force webpack to generate a chunk, defeating the purpose of the eager mode. This PR changes the rule to disallow chunk names when webpackMode: "eager" is set.

Related issue: #1904

[ljharb]

When would you not want this option enabled?

[amsardesai]

Never, really. I'll just make it the default.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 95.87%. Comparing base (c0ac54b) to head (48c921c).

❗ Current head 48c921c differs from pull request most recent head a3a7176. Consider uploading reports for the commit a3a7176 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3004      +/-   ##
==========================================
+ Coverage   95.66%   95.87%   +0.20%     
==========================================
  Files          78       78              
  Lines        3275     3293      +18     
  Branches     1150     1156       +6     
==========================================
+ Hits         3133     3157      +24     
+ Misses        142      136       -6     

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[ljharb]

Is there anyone who this could break? I assume not, because the only complaint would be that it fails to warn on something?

[amsardesai]

Exactly, this only suppresses existing warnings in a narrow case, and doesn't introduce new warnings.

[ljharb]

Thanks, this is great!

One more enhancement we may want to consider before landing this: when webpackMode is eager, and a useless name is present, could we give a suggestion to remove the name?

[amsardesai]

@ljharb Yeah that makes sense to me, just updated the PR to warn when chunk name and eager mode are both set.

[ljharb]

@amsardesai sorry if i wasn't clear; a "suggestion" isn't prose giving the user a hint, it's an actual eslint feature where the editor will prompt them with multiple autofixes they have to explicitly choose. For an example, look for a rule with hasSuggestions: true in its schema.

[amsardesai]

Ah, I didn't realize you meant ESLint suggestions. Let me do that.

[amsardesai]

Hey @ljharb, would love to know if this can be merged now, or if any other changes need to be made!

[ljharb]

@amsardesai ok, i've rebased this and it's probably ready to go :-) (assuming tests pass) just wondering about some of the remaining test changes (not the additions, those make sense) - some are lazy → eager, and some are eager → lazy. Can you go through and comment in the PR on those lines, and explain what motivated the change? i suspect you have a convincing explanation for them all but this way it'll be documented for me in the future :-)

[amsardesai]

Also updated some tests to be a bit more thorough!