feat(eslint-plugin): [no-float-prom] fixer + msg for ignoreVoid

[phaux]

I added an alternative message for when the ignoreVoid option is enabled so that the feature is more discoverable.

When the option is enabled the message is:

Promises must be handled appropriately or explicitly marked as ignored with the void operator

[typescript-eslint]

Thanks for the PR, @phaux!

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.

Thanks again!

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[bradzacher]

LGTM - I think this would be even better as a suggestion fixer.

[bradzacher]

This would probably be better as a suggestion fixer, to make it easy to fix to.

Suggested change

	messageId: options.ignoreVoid ? 'floatingVoid' : 'floating',
	messageId: options.ignoreVoid ? 'floatingVoid' : 'floating',
	suggest: options.ignoreVoid ? [
	{
	messageId: 'xxx', // Consider explicitly marking
	fix(fixer) { /* ... */ }
	},
	] : [],

[phaux]

But won't that autofix with the --fix eslint argument? Or eslint.fixAll code action in vscode? That would suck because I think it should be the developer's conscious decision.

[bradzacher]

Nope, that's the beauty of eslint suggestions!

For fixers, there is exactly 0 or 1 fixers for each report. A fixer will be applied by eslint's --fix mode, if it exists for a report.

For suggestion fixers, on the other hand, can have 0..n suggestions for each report. Each suggestion has its own message which is used to communicate what it does to the user. Each suggestion is not automatically applied by eslint's --fix mode.

Suggestions were added relatively recently, and are great for doing these sorts of fixes - ones that might break code, or require conscious decisions from the user. And the fact that you can present multiple for a report means that you can present the user with options for correcting the error.

[phaux]

Done!

[codecov]

Codecov Report

Merging #1473 into master will decrease coverage by 0.04%.
The diff coverage is 93.88%.

@@            Coverage Diff             @@
##           master    #1473      +/-   ##
==========================================
- Coverage   95.56%   95.51%   -0.05%     
==========================================
  Files         145      141       -4     
  Lines        6577     6450     -127     
  Branches     1879     1841      -38     
==========================================
- Hits         6285     6161     -124     
+ Misses        111      105       -6     
- Partials      181      184       +3

Impacted Files	Coverage Δ
...nt-plugin/src/rules/indent-new-do-not-use/index.ts	98.4% <ø> (ø)	⬆️
...s/eslint-plugin/src/rules/interface-name-prefix.ts	100% <ø> (+16.66%)	⬆️
...rimental-utils/src/ts-eslint-scope/ScopeManager.ts	100% <ø> (ø)	⬆️
...nt-plugin/src/rules/no-unused-vars-experimental.ts	91.39% <ø> (ø)	⬆️
...ges/eslint-plugin/src/rules/no-inferrable-types.ts	93.1% <ø> (ø)	⬆️
packages/eslint-plugin/src/rules/indent.ts	92.68% <ø> (ø)	⬆️
...ges/experimental-utils/src/ts-eslint/SourceCode.ts	100% <ø> (ø)	⬆️
...experimental-utils/src/ts-eslint-scope/Variable.ts	100% <ø> (ø)	⬆️
packages/eslint-plugin/src/rules/no-type-alias.ts	100% <ø> (ø)	⬆️
...es/experimental-utils/src/ts-eslint-scope/Scope.ts	100% <ø> (ø)	⬆️
... and 45 more

[bradzacher]

LGTM - thanks for this.