Parsing error: Cannot read property 'map' of undefined on import when a function has an array return type

[mwiedmann]

• I have tried restarting my IDE and the issue persists.
• I have updated to the latest version of the packages.
• I have read the FAQ and my problem is not listed.

Repro

// some export in a file1.ts, it doesn't matter what you export
export type Foo = number

// file2.ts, import from file1.ts and have an array return type on a function.
// The [sometype] return type seems to be the key to causing the issue.
import { Foo } from './test-import' // This line has error: "Parsing error: Cannot read property 'map' of undefined"

export function foo(id: Foo): [number] { // The [number] or any array return type seems to be the cause
  return [id]
}

Expected Result
I expected it not to fail.

Actual Result
Parsing error: Cannot read property 'map' of undefined

[bradzacher]

What version of our tooling are you using?
That section is part of our template for a reason.

As mentioned in the first comment in the template:

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If you ignore it, we're just going to respond asking you to fill it out, which wastes everyone's time.
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[mwiedmann]

"@typescript-eslint/eslint-plugin": "4.0.0",
"@typescript-eslint/parser": "4.0.0",
"eslint": "7.7.0",
"typescript": "4.0.2",

[bradzacher]

TS4.0 included a breaking change to their AST shape which we've properly handled since our v3.3.0 release.
If you've got v4 of our packages installed and you're still seeing errors, likely you also have older version(s) of our tooling installed alongside the new versions, and your local tooling is using the older versions.

See discussion in: #2260
Packages like react-scripts (part of create react app) will depend on their own (older) versions of our packages. You will have to use resolutions to bypass.

[mwiedmann]

Yes. Confirmed that we did have an older version of the parser being pulled in by another package. Terribly sorry about this. Working fine now.