Function findPython

lib/cli.js:134–197

* Find a suitable Python >= 3.11 interpreter. * * Search order is platform-dependent: * Windows: python -> py -3 -> python3 * macOS/Linux: python3 -> python * * The AUTOFORGE_PYTHON env var overrides automatic detection. * * After finding a candidate we also verify that the venv modu

()

 * available (Debian/Ubuntu strip it out of the base package).
 */
function findPython() {
  // Allow explicit override via environment variable
  const override = process.env.AUTOFORGE_PYTHON;
  if (override) {
    const result = tryPythonCandidate(override);
    if (!result) {
      die(`AUTOFORGE_PYTHON is set to "${override}" but it could not be executed.`);
    }
    if (result.tooOld) {
      die(
        `Python ${result.version.raw} found (via AUTOFORGE_PYTHON), but 3.11+ required.\n` +
        '  Install Python 3.11+ from https://python.org'
      );
    }
    return result;
  }

  // Platform-specific candidate order
  const candidates = IS_WIN
    ? ['python', ['py', '-3'], 'python3']
    : ['python3', 'python'];

  let bestTooOld = null;

  for (const candidate of candidates) {
    const result = tryPythonCandidate(candidate);
    if (!result) continue;

    if (result.tooOld) {
      // Remember the first "too old" result for a better error message
      if (!bestTooOld) bestTooOld = result;
      continue;
    }

    // Verify venv module is available (Debian/Ubuntu may need python3-venv)
    try {
      const exeParts = result.exe.split(' ');
      execFileSync(exeParts[0], [...exeParts.slice(1), '-c', 'import ensurepip'], {
        encoding: 'utf8',
        timeout: 10_000,
        stdio: ['pipe', 'pipe', 'pipe'],
      });
    } catch {
      die(
        `Python venv module not available.\n` +
        `  Run: sudo apt install python3.${result.version.minor}-venv`
      );
    }

    return result;
  }

  // Provide the most helpful error message we can
  if (bestTooOld) {
    die(
      `Python ${bestTooOld.version.raw} found, but 3.11+ required.\n` +
      '  Install Python 3.11+ from https://python.org'
    );