oxc-project/oxc · error · OxcDiagnostic

Multiple exports of name '{name}'.

Error message

Multiple exports of name '{name}'.

What it means

The star-conflict branch of `import/export`'s duplicate-name check: a name that this module exports directly also appears among the named exports of a module reached through `export *`. The diagnostic labels both the local export span and every conflicting star-export span (built with `LabeledSpan::underline`) so the shadowing is visible.

Source

Thrown at crates/oxc_linter/src/rules/import/export.rs:106

            } else {
                all_export_names.insert(star_export_entry.span, export_names);
            }
        });

        for (name, span) in named_export {
            let mut spans = all_export_names
                .iter()
                .filter_map(|(star_export_entry_span, export_names)| {
                    if export_names.contains(name) { Some(*star_export_entry_span) } else { None }
                })
                .collect::<Vec<_>>();

            if !spans.is_empty() {
                spans.push(*span);
                let labels = spans.into_iter().map(LabeledSpan::underline).collect::<Vec<_>>();

                ctx.diagnostic(
                    OxcDiagnostic::warn(format!("Multiple exports of name '{name}'."))
                        .with_help("Rename or remove the duplicate export so each name is exported only once.")
                        .with_labels(labels),
                );
            }
        }
    }
}

struct ExportNameSpans {
    spans: Vec<Span>,
    has_named_specifier: bool,
}

fn diagnose_duplicate_named_exports(ctx: &LintContext<'_>, module_record: &ModuleRecord) {
    let mut export_names: FxHashMap<(CompactStr, bool), ExportNameSpans> = FxHashMap::default();

    module_record
        .local_export_entries

View on GitHub (pinned to e1e7af627c)

Solutions

1. Rename or remove the local export so it no longer collides with the star-exported name
2. Replace `export *` with an explicit named list that omits the colliding name
3. Namespace the re-export: `export * as mod from './mod';`

Example fix

// before — 'a' exists locally and is also exported by mod
export const a = 1;
export * from './mod';

// after
export const a = 1;
export { b, c } from './mod'; // explicit list, omit 'a'

// .oxlintrc.json
{
  "plugins": ["import"],
  "rules": { "import/export": "error" }
}
// CI gate: npx oxlint src/ && npx tsc --noEmit  // tsc also flags ambiguous star re-exports

When it happens

Trigger: `export const a = 1;` together with `export * from './mod';` where mod also exports `a` — the star re-export of that name is shadowed by the local export, and both sites are reported.

Common situations: Barrel index files adding star exports next to local constants; two package versions re-exporting the same helper name; adding a new local export that collides with one already re-exported from a dependency.

Related errors

• No named exports found in module '{module_name}'
• Type imports from declaration files must use top-level `impo
• Prefer using inline type specifiers instead of a top-level t
• Prefer using a top-level type-only import instead of inline
• Prefer using a top-level type-only import instead of inline

AI-assisted analysis of oxc-project/oxc@e1e7af627c (2026-08-20). Data as JSON: /api/errors/db2355536229ca4b. Report an issue: GitHub.