What causes "Setter cannot return a value" in oxc-project/oxc?

Change to a bare `return;` or remove the return statement entirely.

oxc-project/oxc · warning · OxcDiagnostic

Setter cannot return a value

Error message

Setter cannot return a value

What it means

oxlint's port of ESLint `no-setter-return`. Per the ECMAScript spec the value returned from a setter's `return` statement is ignored, so `return someValue;` inside a `set` accessor is dead data that misleads readers. The rule flags any `return <expr>;` inside a setter.

Source

Thrown at crates/oxc_linter/src/rules/eslint/no_setter_return.rs:9

use oxc_ast::AstKind;
use oxc_diagnostics::OxcDiagnostic;
use oxc_macros::declare_oxc_lint;
use oxc_span::Span;

use crate::{AstNode, context::LintContext, rule::Rule};

fn no_setter_return_diagnostic(span: Span) -> OxcDiagnostic {
    OxcDiagnostic::warn("Setter cannot return a value")
        .with_help("Remove the return statement or ensure it does not return a value.")
        .with_label(span)
}

#[derive(Debug, Default, Clone)]
pub struct NoSetterReturn;

declare_oxc_lint!(
    /// ### What it does
    ///
    /// Setters cannot return values.
    ///
    /// This rule can be disabled for TypeScript code, as the TypeScript compiler
    /// enforces this check.
    ///
    /// ### Why is this bad?
    ///
    /// While returning a value from a setter does not produce an error, the returned value is

View on GitHub (pinned to e1e7af627c)

Solutions

Change to a bare `return;` or remove the return statement entirely.
If the value must flow onward, restructure the API as a normal method (`setName(v)`).

Example fix

// before
set name(v) {
  this._name = v;
  return v;
}

// after
set name(v) {
  this._name = v;
}

Defensive patterns

Strategy: validation

Validate before calling

// Rough guard: `return <expr>;` inside a set accessor
function setterReturnValue(src) {
  const setters = [...src.matchAll(/\bset\s+\w+\s*\([^)]*\)\s*\{([\s\S]*?)\}/g)];
  return setters.some(m => /return\s+[^;\s]/.test(m[1]));
}

Prevention

Setters should only mutate; make them `return;`-free entirely.
If callers need the value back, model the operation as a plain method instead of an accessor.
When copying a getter into a setter, delete its return statement as part of the edit.

When it happens

Trigger: `set name(v) { this._name = v; return v; }` — also `return this._name = v;` (which trips both this rule and no-return-assign). Bare `return;` inside a setter is allowed.

Common situations: Copy-pasting a getter body into a setter; developers expecting chainability that the language does not provide.

Related errors

AI-assisted analysis of oxc-project/oxc@e1e7af627c (2026-08-20). Data as JSON: /api/errors/b4ba39238eaf8001. Report an issue: GitHub.