feat(eslint-plugin): new extended rule 'no-invalid-this'

[anikethsaha]

Supports functions with a this argument

Fixes #604

[typescript-eslint]

Thanks for the PR, @anikethsaha!

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[anikethsaha]

@bradzacher any suggestion to fix this ?

[bradzacher]

The error message gives you the reason that it is incompatible:

Argument of type '(param: TSESTree.Identifier) => string' is not assignable to parameter of type '(value: Parameter, index: number, array: Parameter[]) => string'.

You're attempting to assign a function with signature (param: TSESTree.Identifier) => string to a location that accepts (param: TSESTree.Parameter) => string.

This is an error, TSESTree.Parameter contains more types than just Identifier.

[anikethsaha]

I did try with TSESTree.Parameter in 1st commit of this PR. f274634#diff-7fcf937f6ab4b17e2b9aa4126d5b950fR63

but that one failed as well.

[bradzacher]

Why bother adding an explicit type to the param? Just let TS infer the type from the usage.

node.params.map(param => { ... });

[anikethsaha]

implicit is Parameter I guess

  const names = node.params.map(param => param.name);

[bradzacher]

mostly LGTM, a few comments.
Thanks for this!

[bradzacher]

FYI - the CI is failing

[anikethsaha]

FYI - the CI is failing

on it.

[anikethsaha]

I am not sure whats wrong but all invalid test cases are failing in ruleTester

also, still blocked with this

[codecov]

Codecov Report

Merging #1823 into master will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #1823      +/-   ##
==========================================
+ Coverage   93.88%   93.90%   +0.01%     
==========================================
  Files         170      171       +1     
  Lines        7737     7758      +21     
  Branches     2227     2230       +3     
==========================================
+ Hits         7264     7285      +21     
  Misses        218      218              
  Partials      255      255              

Flag	Coverage Δ
#unittest	93.90% <100.00%> (+0.01%)	⬆️

Impacted Files	Coverage Δ
...ackages/eslint-plugin/src/rules/no-invalid-this.ts	100.00% <100.00%> (ø)

[bradzacher]

LGTM - thanks for this

[bajtos]

This is awesome, thank you @anikethsaha for implementing the new rule ❤️