fix(eslint-plugin): naming-convention null pattern

[jonathanrdelgado]

I just switched over to the new naming-convention rule (which is pretty awesome), I was getting an exception TypeError: Cannot read property 'type' of null, here is a quick repo:

const match = 'test'.match(/test/);
const [, key, value] = match;

With the minimum configuration of

{
  selector: 'default',
  format: ['camelCase'],
}

This is the case because the AST_NODE_TYPES.ArrayPattern was returning an array of elements in which the first element is null, then, when we recursively step back into getIdentifiersFromPattern, we're immediately evaluating null.type.

The solution I'm proposing is just filtering out those null elements in the loop prior to recursion. I added a regression test as well.

Thank you!

[typescript-eslint]

Thanks for the PR, @jonathanrdelgado!

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]

Nice catch! thanks for fixing this.
Turns out the types for ArrayPattern are wrong - I didn't even realise! I'll submit a separate PR to fix this.

[codecov]

Codecov Report

Merging #1450 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           master   #1450      +/-   ##
=========================================
+ Coverage   94.09%   94.1%   +<.01%     
=========================================
  Files         143     143              
  Lines        6457    6458       +1     
  Branches     1823    1824       +1     
=========================================
+ Hits         6076    6077       +1     
  Misses        204     204              
  Partials      177     177

Impacted Files	Coverage Δ
...kages/eslint-plugin/src/rules/naming-convention.ts	87.88% <100%> (+0.03%)	⬆️