no-constructor-return

Disallow returning value from constructor

In JavaScript, returning a value in the constructor of a class may be a mistake. Forbidding this pattern prevents mistakes resulting from unfamiliarity with the language or a copy-paste error.

Rule Details

This rule disallows return statements in the constructor of a class. Note that returning nothing is allowed.

Examples of incorrect code for this rule:

/*eslint no-constructor-return: "error"*/ class A { constructor(a) { this.a = a; return a; } } class B { constructor(f) { if (!f) { return 'falsy'; } } } 
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Examples of correct code for this rule:

/*eslint no-constructor-return: "error"*/ class C { constructor(c) { this.c = c; } } class D { constructor(f) { if (!f) { return; // Flow control. } f(); } } class E { constructor() { return; } } 
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Version

This rule was introduced in ESLint v6.7.0.

Resources

• Rule source
• Tests source