astral-sh/uv · error

Expected the output filename to be `pylock.toml` or `pylock.

Error message

Expected the output filename to be `pylock.toml` or `pylock.<name>.toml`, where `<name>` is non-empty and contains no dots; found `{file_name}`

What it means

Error "Expected the output filename to be `pylock.toml` or `pylock.<name>.toml`, where `<name>` is non-empty and contains no dots; found `{file_name}`" thrown in astral-sh/uv.

Source

Thrown at crates/uv/src/commands/project/export.rs:373

        } else {
            ExportFormat::RequirementsTxt
        }
    });

    // Skip conflict detection for CycloneDX exports, as SBOMs are meant to document all dependencies including conflicts.
    if !matches!(format, ExportFormat::CycloneDX1_5) {
        detect_conflicts(&target, &extras, &groups)?;
    }

    // If the user is exporting to PEP 751, ensure the filename matches the specification.
    if matches!(format, ExportFormat::PylockToml) {
        if let Some(file_name) = output_file
            .as_deref()
            .and_then(Path::file_name)
            .and_then(OsStr::to_str)
        {
            if !is_pylock_toml(file_name) {
                return Err(anyhow!(
                    "Expected the output filename to be `pylock.toml` or `pylock.<name>.toml`, where `<name>` is non-empty and contains no dots; found `{file_name}`",
                ));
            }
        }
    }

    // Generate the export.
    match format {
        ExportFormat::RequirementsTxt => {
            let export = RequirementsTxtExport::from_lock(
                &target,
                &prune,
                &extras,
                &groups,
                include_annotations,
                editable,
                hashes,
                &install_options,

View on GitHub (pinned to f1a42680ff)

When it happens

Trigger: Thrown at crates/uv/src/commands/project/export.rs:373 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of astral-sh/uv@f1a42680ff (2026-08-16). Data as JSON: /api/errors/e7a70273ffdd855e. Report an issue: GitHub.