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no-unnecessary-assignment

Disallows useless assignments.

Rule Details​

Sometimes, refactoring can lead to assignment statements that were once useful but are now redundant. This rule helps you clean up the dead code in a similar way that the @typescript-eslint/no-unnecessary-condition rule does.

// Bad
declare let foo: 1;
declare let bar: 1;
foo = bar;

// Bad
declare let foo: number;
foo += 0;

// Bad
declare let foo: string;
foo += "";

// Bad
declare const foo: boolean;
const bar = foo || false;
const baz = foo && true;

// Bad
declare const foo: number;
const bar = foo || 0;

// Bad
declare const foo: string;
const bar = foo || "";

// Bad
declare const foo: string | null;
const bar = foo ?? null;

// Bad
declare const foo: string | undefined;
const bar = foo ?? undefined;

Note that while "<<" is technically a useless operator when combined with 0, this rule will not report on it so that bit flag enums will not cause false positives.

Options and Defaults​

{
  "rules": {
    "complete/no-unnecessary-assignment": "error"
  }
}

This rule is not configurable.

Resources​