fix(eslint-plugin): [brace-style] handle enum declarations

[a-tarasyuk]

Fixes #1274

[typescript-eslint]

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[codecov]

Codecov Report

Merging #1281 into master will increase coverage by 0.13%.
The diff coverage is 95.12%.

@@            Coverage Diff             @@
##           master    #1281      +/-   ##
==========================================
+ Coverage   93.93%   94.06%   +0.13%     
==========================================
  Files         131      131              
  Lines        5804     5781      -23     
  Branches     1639     1630       -9     
==========================================
- Hits         5452     5438      -14     
+ Misses        188      184       -4     
+ Partials      164      159       -5

Impacted Files	Coverage Δ
packages/eslint-plugin/src/util/astUtils.ts	100% <100%> (+7.14%)	⬆️
packages/eslint-plugin/src/rules/brace-style.ts	95.23% <94.87%> (-4.77%)	⬇️
...slint-plugin/src/rules/no-unnecessary-condition.ts	100% <0%> (ø)	⬆️
...s/eslint-plugin/src/rules/no-unused-expressions.ts	100% <0%> (ø)	⬆️
...lint-plugin/src/rules/prefer-nullish-coalescing.ts	93.61% <0%> (ø)	⬆️
packages/eslint-plugin/src/util/misc.ts	88% <0%> (+1.79%)	⬆️
...ackages/eslint-plugin/src/rules/member-ordering.ts	97.33% <0%> (+5.02%)	⬆️
...s/eslint-plugin/src/rules/no-non-null-assertion.ts	100% <0%> (+15.62%)	⬆️

[bradzacher]

How come you chose to reimplement the rule logic instead of using the old monkey patch?

[a-tarasyuk]

@bradzacher monkey patching is good., validateCurlyPair is not a public method, it is located inside .create. TSEnumDeclaration doesn't have Block and we cannot use public hooks like BlockStatement, (sourceCode.getLastToken(node) returns wrong token for TSEnumDeclaration }). So, we need to get the correct last token (}) for TSEnumDeclaration and then check curly pairs.

If this PR doesn't make sense I'm OK to close it.

[bradzacher]

No, it's all good - I didn't realise that the enum ast node didn't have a body, sorry.
I'm not quite sure why we don't have a body for enums (I've raised #1305 - it seems like an oversight when the enum node was created, but that won't help you right now).

Your approach is correct, given the lack of a body.

[bradzacher]

LGTM - thanks for this

[nolazybits]

Thank you!