Function readRawSymref

src/utils/git/gitFilesystem.ts:287–309

(
  gitDir: string,
  refPath: string,
  branchPrefix: string,
)

 * Checks loose file only — packed-refs doesn't store symrefs.
 */
export async function readRawSymref(
  gitDir: string,
  refPath: string,
  branchPrefix: string,
): Promise<string | null> {
  try {
    const content = (await readFile(join(gitDir, refPath), 'utf-8')).trim()
    if (content.startsWith('ref:')) {
      const target = content.slice('ref:'.length).trim()
      if (target.startsWith(branchPrefix)) {
        const name = target.slice(branchPrefix.length)
        // Reject path traversal and argument injection from a tampered symref.
        if (!isSafeRefName(name)) {
          return null
        }
        return name
      }
    }
  } catch {
    // Not a loose ref
  }
  return null
}

// ---------------------------------------------------------------------------
// GitFileWatcher — watches git files and caches derived values.