selfAssignments

Reports self-assignments which have no effect and are likely errors.

✅ This rule is included in the ts logical and logicalStrict presets.

Self-assignments where a variable is assigned to itself have no effect and typically indicate an incomplete refactoring or a copy-paste error. These assignments serve no purpose and should be removed or corrected to assign the intended value.

Examples

❌ Incorrect

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

count &&= count;
Error ts(2588)  ― Cannot assign to 'count' because it is a constant.

flags.value ||= flags.value;

data ??= data;
Error ts(2588)  ― Cannot assign to 'data' because it is a constant.

✅ Correct

value = newValue;
Error ts(2588)  ― Cannot assign to 'value' because it is a constant.

count &&= otherCount;
Error ts(2588)  ― Cannot assign to 'count' because it is a constant.

flag ||= defaultFlag;
Error ts(2588)  ― Cannot assign to 'flag' because it is a constant.

data ??= fallbackData;
Error ts(2588)  ― Cannot assign to 'data' because it is a constant.

Options

This rule is not configurable.

When Not To Use It

There are rarely valid reasons to use self-assignment. In cases where you need to trigger getters/setters or proxies, consider adding a comment explaining the intentional self-assignment.

Further Reading

• MDN: Assignment operators
• MDN: Logical AND assignment
• MDN: Logical OR assignment
• MDN: Nullish coalescing assignment

Equivalents in Other Linters

• Biome: noSelfAssign
• Deno: no-self-assign
• ESLint: no-self-assign
• Oxlint: eslint/no-self-assign