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• I have tried restarting my IDE and the issue persists.
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Issue Description

const users: Record<string, string> = {};
export const getUser = (name: string) => {
  users[name] ??= 'hei';
  return users[name]!; // Error: @typescript-eslint/no-unnecessary-type-assertion
};

const groups: Record<string, string> = {};
export const getGroup = (name: string) => {
  name = `${name}-grp`;
  groups[name] ??= 'hei';
  return groups[name]!; // No error!
};

I expected that the return from both functions should produce the @typescript-eslint/no-unnecessary-type-assertion error. Only the first does. If I remove noUncheckedIndexedAccess, I get the expected behavior.

Reproduction Repository Link

https://stackblitz.com/edit/vitejs-vite-imvtqxsz?file=src%2Ffoo.ts

Repro Steps

1. Open the StackBlitz
2. npx eslint .

Versions