[no-unsafe-return] TypeError: checker.getTypeArguments is not a function

[tao-cumplido]

The rule no-unsafe-return exits with an error on array types with TS versions < 3.7
Apparently the rule uses the method getTypeArguments which was only added to the TS api in version 3.7: https://github.com/microsoft/TypeScript-wiki/blob/master/API-Breaking-Changes.md

Repro

module.exports = {
   parser: '@typescript-eslint/parser',
   plugins: ['@typescript-eslint'],
   parserOptions: {
      project: './tsconfig.json',
   },
   rules: {
      '@typescript-eslint/no-unsafe-return': 'error',
   },
};

function foo() {
   return [];
}

I created a minimal repo here: https://github.com/tao-cumplido/ts-eslint-error
If you bump the TS version to 3.7 it works as expected.

Expected Result
no error

Actual Result

TypeError: checker.getTypeArguments is not a function
Occurred while linting C:\Users\taocu\Desktop\Projekte\ts-eslint-error\test.ts:2
    at Object.isAnyOrAnyArrayTypeDiscriminated (C:\Users\taocu\Desktop\Projekte\ts-eslint-error\node_modules\@typescript-eslint\eslint-plugin\dist\util\types.js:242:31)
    at checkReturn (C:\Users\taocu\Desktop\Projekte\ts-eslint-error\node_modules\@typescript-eslint\eslint-plugin\dist\rules\no-unsafe-return.js:49:34)
    at ReturnStatement (C:\Users\taocu\Desktop\Projekte\ts-eslint-error\node_modules\@typescript-eslint\eslint-plugin\dist\rules\no-unsafe-return.js:105:17)
    at C:\Users\taocu\Desktop\Projekte\ts-eslint-error\node_modules\eslint\lib\linter\safe-emitter.js:45:58
    at Array.forEach (<anonymous>)
    at Object.emit (C:\Users\taocu\Desktop\Projekte\ts-eslint-error\node_modules\eslint\lib\linter\safe-emitter.js:45:38)
    at NodeEventGenerator.applySelector (C:\Users\taocu\Desktop\Projekte\ts-eslint-error\node_modules\eslint\lib\linter\node-event-generator.js:254:26)
    at NodeEventGenerator.applySelectors (C:\Users\taocu\Desktop\Projekte\ts-eslint-error\node_modules\eslint\lib\linter\node-event-generator.js:283:22)
    at NodeEventGenerator.enterNode (C:\Users\taocu\Desktop\Projekte\ts-eslint-error\node_modules\eslint\lib\linter\node-event-generator.js:297:14)
    at CodePathAnalyzer.enterNode (C:\Users\taocu\Desktop\Projekte\ts-eslint-error\node_modules\eslint\lib\linter\code-path-analysis\code-path-analyzer.js:634:23)
error Command failed with exit code 2.

Additional Info

Versions

package	version
@typescript-eslint/eslint-plugin	2.25.0
@typescript-eslint/parser	2.25.0
TypeScript	3.6.x
ESLint	6.8.0
node	13.10.1
npm	6.13.7

[bradzacher]

Ahhh. Another thing #1752 would have caught.
I probably need to get that implemented sooner rather than later.

Thanks for reporting!