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constructorReturns

Reports returning values from constructor functions.

✅ This rule is included in the ts javascript presets.

In JavaScript, returning a value from a constructor overrides the newly created instance. This behavior is generally unintentional and can lead to unexpected results where the returned value becomes the result of the new expression instead of the instance.

While JavaScript technically allows this, it’s generally a code smell that indicates a design issue. If you need to return a different object based on constructor parameters, consider using a factory function instead.

Examples

Section titled “Examples”
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Options

Section titled “Options”

This rule is not configurable.

When Not To Use It

Section titled “When Not To Use It”

If you have a rare use case where you intentionally need to return different objects from a constructor, you might choose to disable this rule for those specific cases. However, this is generally considered an anti-pattern, and you should strongly consider refactoring to use a factory function instead.

Further Reading

Section titled “Further Reading”

Equivalents in Other Linters

Section titled “Equivalents in Other Linters”