returnAssignments

Reports using assignment expressions in return statements.

✅ This rule is included in the ts stylistic and stylisticStrict presets.

Using assignments in return statements can make code harder to read and can lead to confusion about whether the assignment or the returned value is the primary intent. Assignment expressions return the assigned value, but mixing assignment with return makes the control flow less clear.

Examples

❌ Incorrect

function getValue() {
  let value;
  return (value = 1);
}

function process() {
  let result;
  return (result = calculate());
}

const arrow = () => (value = 42);
Error ts(2588)  ― Cannot assign to 'value' because it is a constant.

function compound() {
  let count;
  return (count += 5);
}

✅ Correct

function getValue() {
  let value = 1;
  return value;
}

function process() {
  let result = calculate();
  return result;
}

const arrow = () => {
  const value = 42;
  return value;
};

function compound() {
  let count = 0;
  count += 5;
  return count;
}

Options

This rule is not configurable.

When Not To Use It

If your codebase uses assignments in return statements as a common idiom and you find them readable, you might choose to disable this rule. However, separating assignments from return statements generally improves code clarity and reduces potential for confusion.

Further Reading

• MDN: return statement
• MDN: Assignment operators

Equivalents in Other Linters

• ESLint: no-return-assign
• Oxlint: eslint/no-return-assign