oxc-project/oxc · error · OxcDiagnostic

Unexpected unnamed {inferred_name_or_description}.

Error message

Unexpected unnamed {inferred_name_or_description}.

What it means

Lint diagnostic from eslint/func-names: an anonymous function expression was found in a position where no name can be inferred (e.g. an IIFE or an unassigned expression), so the function will show as '(anonymous)' in stack traces and profilers.

Source

Thrown at crates/oxc_linter/src/rules/eslint/func_names.rs:35

use schemars::JsonSchema;
use serde::Deserialize;

use crate::{
    AstNode,
    ast_util::get_function_name_with_kind,
    context::LintContext,
    fixer::{RuleFix, RuleFixer},
    rule::{Rule, TupleRuleConfig},
};

fn named_diagnostic(function_name: &str, span: Span) -> OxcDiagnostic {
    OxcDiagnostic::warn(format!("Unexpected named {function_name}."))
        .with_label(span)
        .with_help("Remove the name on this function expression.")
}

fn unnamed_diagnostic(inferred_name_or_description: &str, span: Span) -> OxcDiagnostic {
    OxcDiagnostic::warn(format!("Unexpected unnamed {inferred_name_or_description}."))
        .with_label(span)
        .with_help("Consider giving this function expression a name.")
}

#[derive(Debug, Default, Clone, Copy, PartialEq, JsonSchema, Deserialize)]
#[serde(rename_all = "kebab-case")]
enum FuncNamesConfigType {
    /// Requires all function expressions to have a name.
    #[default]
    Always,
    /// Requires a name only if one is not automatically inferred.
    AsNeeded,
    /// Disallows names for function expressions.
    Never,
}

#[derive(Debug, Default, Clone, JsonSchema, Deserialize)]
#[serde(default)]

View on GitHub (pinned to e1e7af627c)

Solutions

1. Give the function expression a name
2. Assign the expression to a variable or property so a name can be inferred
3. Configure the rule (allowExpressions/allowAnonymousFunctions equivalents) if anonymous functions are intentional in this position

When it happens

Trigger: Thrown at crates/oxc_linter/src/rules/eslint/func_names.rs:35 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of oxc-project/oxc@e1e7af627c (2026-08-20). Data as JSON: /api/errors/d8ec682f0c969001. Report an issue: GitHub.