Method listInstalledPythons

packages/python/src/uv.ts:78–129

* List installed Python versions managed by uv. * Excludes system Python.

()

   * Excludes system Python.
   */
  listInstalledPythons(): Set<string> {
    let output: string;
    try {
      output = execFileSync(
        this.uvPath,
        ['python', 'list', '--only-installed', '--output-format', 'json'],
        {
          encoding: 'utf8',
          stdio: ['pipe', 'pipe', 'pipe'],
          shell: isWin,
        }
      );
    } catch (err) {
      throw new Error(
        `Failed to run 'uv python list': ${err instanceof Error ? err.message : String(err)}`
      );
    }

    if (!output || output.trim() === '' || output.trim() === '[]') {
      return new Set();
    }

    let pyList: UvPythonEntry[];
    try {
      pyList = JSON.parse(output);
    } catch (err) {
      throw new Error(
        `Failed to parse 'uv python list' output: ${err instanceof Error ? err.message : String(err)}`
      );
    }

    // Only apply the startsWith filter when in Vercel Build Image
    // (local builds use system Python paths, not /uv/python/)
    if (process.env.VERCEL_BUILD_IMAGE) {
      pyList = pyList.filter(
        entry =>
          entry.path !== null &&
          entry.path.startsWith(UV_PYTHON_PATH_PREFIX) &&
          entry.implementation === 'cpython'
      );
    } else {
      pyList = pyList.filter(
        entry => entry.path !== null && entry.implementation === 'cpython'
      );
    }

    return new Set(
      pyList.map(
        entry => `${entry.version_parts.major}.${entry.version_parts.minor}`
      )
    );
  }

  async sync(options: {
    venvPath: string;