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`prefer-string-starts-ends-with`: incorrect autofix when string does not exist

See original GitHub issue

Problem

If the string variable is null or undefined, the autofix will cause an exception.

Before autofix:

/^en/.test(lang)
// Returns `false` if `lang` is `undefined` / `null`

After autofix:

lang.startsWith('en')
// Uncaught TypeError: Cannot read property 'startsWith' of undefined

Fix

A year from now when we drop support for Node 12, we can use optional chaining to autofix this safely:

lang?.startsWith('en')

Until then, we have a few options:

Do nothing since the autofixer has been around or a year (#711) and no one else has complained
Temporarily turn the autofixer into an automated suggestion until we can use the optional chaining autofix
Warn about this situation in the rule doc

Issue Analytics

State:
Created 2 years ago
Comments:16

Top GitHub Comments

2reactions

bmishcommented, May 14, 2021

Sure I’ll work on it.

0reactions

fiskercommented, May 14, 2021

Want work on it?

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