feat(eslint-plugin): [type-annotation-spacing] handle space between ? and :

[Knutas]

Fixes type-annotation-spacing rule to give an error if there is a space between ? and : in a type annotation.

Fixes #3140

[typescript-eslint]

Thanks for the PR, @Knutas!

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[codecov]

Codecov Report

Merging #3138 (ae1372e) into master (9323eae) will increase coverage by 0.02%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #3138      +/-   ##
==========================================
+ Coverage   92.88%   92.90%   +0.02%     
==========================================
  Files         315      316       +1     
  Lines       10706    10842     +136     
  Branches     3025     3065      +40     
==========================================
+ Hits         9944    10073     +129     
- Misses        342      343       +1     
- Partials      420      426       +6     

Flag	Coverage Δ
unittest	92.90% <100.00%> (+0.02%)	⬆️

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

Impacted Files	Coverage Δ
...eslint-plugin/src/rules/type-annotation-spacing.ts	80.82% <100.00%> (+0.82%)	⬆️
...-plugin/src/rules/no-unnecessary-type-assertion.ts	94.66% <0.00%> (-2.44%)	⬇️
packages/eslint-plugin/src/rules/unbound-method.ts	91.30% <0.00%> (-1.88%)	⬇️
.../eslint-plugin/src/rules/member-delimiter-style.ts	94.28% <0.00%> (-0.63%)	⬇️
...es/eslint-plugin/src/rules/no-floating-promises.ts	100.00% <0.00%> (ø)
...es/eslint-plugin/src/rules/object-curly-spacing.ts	100.00% <0.00%> (ø)
.../eslint-plugin/src/util/explicitReturnTypeUtils.ts	100.00% <0.00%> (ø)
...ackages/eslint-plugin/src/util/getWrappingFixer.ts	93.93% <0.00%> (ø)
packages/typescript-estree/src/convert.ts	98.24% <0.00%> (+<0.01%)	⬆️
packages/eslint-plugin/src/util/types.ts	83.51% <0.00%> (+0.27%)	⬆️
... and 2 more

[bradzacher]

Thanks for the PR!

unless the before option is set to true.

before only applies to space before the pair.
I don't think overloading it with additional meaning is correct here.

If we wanted to allow space between the pair that should be a separate option - an option I would hold off on implementing for now (until someone asks for it).

.

[Knutas]

So change it to always raise this error regardless of options?

[bradzacher]

So change it to always raise this error regardless of options?

Yes please!

[bradzacher]

logic itself LGTM, a few comments.
Thanks for your work on this!

[bradzacher]

isSpaceBetween was only added in ESLint v6.7.0
We currently support as far back as ESLint v5.0.0.

Meaning this is not safe.

You need to fall back to the old sourceCode.isSpaceBetweenTokens() API for those cases.

[Knutas]

I saw that isSpaceBetween was already used by object-curly-spacing so I assumed it was fine to use.

[bradzacher]

I think we could add a custom message here for additional clarity.
Something like Unexpected space between the {{previousToken}} and the {{type}}.

[bradzacher]

LGTM - thanks for your contribution!