Before You File a Bug Report Please Confirm You Have Done The Following...

• I have tried restarting my IDE and the issue persists.
• I have updated to the latest version of the packages.
• I have searched for related issues and found none that matched my issue.
• I have read the FAQ and my problem is not listed.

Playground Link

Playground Link

Repro Code

type T1 = { y: () => number } | null;
declare const x1: T1;
x1?.y()?.toExponential();
//     ^^
//     Error expected for unnecessary optional chaining.

type T2 = (() => number) | undefined;
declare const x2: T2;
x2?.()?.toExponential();
//    ^^
//     Error expected for unnecessary optional chaining.

type T3 = { y: number } | null;
declare const x3: T3;
x3?.y?.toExponential();
//   ^^
//   Error correctly caught.

type T4 = () => number;
declare const x4: T4;
x4()?.toExponential;
//  ^^
//  Error correctly caught.

ESLint Config

module.exports = {
  parser: "@typescript-eslint/parser",
  rules: {
    "@typescript-eslint/no-unnecessary-condition": "error",
  },
};

tsconfig

{
  "compilerOptions": {
    "strictNullChecks": true
  }
}

Expected Result

On lines 3 and 9, I expected there to be an error when using optional chaining on the return value of a method that returns a non-null and non-undefined value following another optional chaining.

Actual Result

On lines 3 and 9, no error was reported.

Additional Info

This is partially related to #1977 and #2111.