oxc-project/oxc · warning · OxcDiagnostic

Class cannot have method named `new`.

Error message

Class cannot have method named `new`.

What it means

Companion diagnostic of no-misused-new for classes: a method literally named `new` on a class is not a constructor, and the name misleads readers. The help at no_misused_new.rs:22-26 recommends renaming it to `constructor`.

Source

Thrown at crates/oxc_linter/src/rules/typescript/no_misused_new.rs:21

    ast::{
        ClassElement, IdentifierReference, PropertyKey, TSSignature, TSType, TSTypeAnnotation,
        TSTypeName,
    },
};
use oxc_diagnostics::OxcDiagnostic;
use oxc_macros::declare_oxc_lint;
use oxc_span::{GetSpan, Span};

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

fn no_misused_new_interface_diagnostic(span: Span) -> OxcDiagnostic {
    OxcDiagnostic::warn("Interfaces cannot be constructed, only classes.")
        .with_help("Consider removing this method from your interface.")
        .with_label(span)
}

fn no_misused_new_class_diagnostic(span: Span) -> OxcDiagnostic {
    OxcDiagnostic::warn("Class cannot have method named `new`.")
        .with_help("This method name is confusing, consider renaming the method to `constructor`")
        .with_label(span)
}

fn get_return_type_identifier<'a, 'b>(
    return_type: Option<&'b TSTypeAnnotation<'a>>,
) -> Option<&'b IdentifierReference<'a>> {
    if let Some(return_type) = return_type
        && let TSType::TSTypeReference(type_ref) = &return_type.type_annotation
        && let TSTypeName::IdentifierReference(id) = &type_ref.type_name
    {
        Some(id)
    } else {
        None
    }
}

#[derive(Debug, Default, Clone)]

View on GitHub (pinned to e1e7af627c)

Solutions

1. Rename the method to `constructor` if it was meant to construct
2. Rename it to `create` or `make` if it is an intentional factory method
3. Delete it if it is dead scaffolding

Example fix

// before
class Foo {
  new() { return new Foo(); }
}

// after
class Foo {
  static create() { return new Foo(); }
}

npx oxlint --deny-warnings .

When it happens

Trigger: `class Foo { new() { ... } }` - a class MethodDefinition named `new`, regardless of signature.

Common situations: Factory-method patterns brought from other languages, typos, code generated from templates that emit `new` as a method name.

Related errors

• Literals should be exposed using readonly fields.
• Literals should be exposed using getters.
• Missing accessibility modifier on {member_type} {name}.
• Public accessibility modifier on {member_type} {name}.
• Unexpected empty class.

AI-assisted analysis of oxc-project/oxc@e1e7af627c (2026-08-20). Data as JSON: /api/errors/16614391d6db9cd3. Report an issue: GitHub.