Function derivePycPath

packages/python/src/compileall.ts:96–108

(
  pyRelPath: string,
  pythonMajor: number,
  pythonMinor: number
)

 * Returns `null` if the input is not a `.py` file.
 */
export function derivePycPath(
  pyRelPath: string,
  pythonMajor: number,
  pythonMinor: number
): string | null {
  if (!pyRelPath.endsWith('.py')) return null;

  const lastSlash = pyRelPath.lastIndexOf('/');
  const dir = lastSlash === -1 ? '' : pyRelPath.slice(0, lastSlash + 1);
  const baseName = pyRelPath.slice(lastSlash + 1, -3); // strip ".py"

  return `${dir}__pycache__/${baseName}.cpython-${pythonMajor}${pythonMinor}.pyc`;
}

export interface BytecodeCollectionResult {
  /** FileFsRef entries for .pyc files, keyed by bundle-relative path. */