Hooks

Where it lives

• hooks/run_hook.jsGitHub ↗
  Read the script

  #!/usr/bin/env node
  /**
   * Cross-platform launcher for the watermarks-remover Claude Code plugin hook.
   *
   * Claude Code runs on Node.js across Windows, macOS, and Linux, so `node` is
   * always available. Python, however, may be `py -3`, `python3`, or `python`
   * depending on platform and installation. This runner probes each candidate to
   * confirm it exists and is a Python 3.10+ interpreter (the repository's floor)
   * before committing to it, then proxies stdin/stdout/stderr and the exit code
   * straight through to hook_written_file.py.
   */
  
  const { spawn, execFile } = require('child_process');
  const path = require('path');
  
  const script = path.resolve(__dirname, '..', 'service', 'scripts', 'hook_written_file.py');
  
  const isWin = process.platform === 'win32';
  const candidates = isWin
    ? [
        ['py', ['-3']],
        ['python', []],
        ['python3', []],
      ]
    : [
        ['python3', []],
        ['python', []],
      ];
  
  // Repo requirement: Python 3.10+ stdlib only. `python` may be Python 2 or an
  // older Python 3, so the probe must reject anything below this floor.
  const VERSION_CHECK = 'import sys; sys.exit(0 if sys.version_info >= (3, 10) else 1)';
  
  // The interpreter we committed to running. Guarding on this means a candidate
  // that failed to spawn (ENOENT) cannot let its later `close` event terminate
  // the process out from under a fallback candidate already running.
  let active = null;
  
  function run(cmd, extraArgs, index) {
    const args = [...extraArgs, script, ...process.argv.slice(2)];
    const child = spawn(cmd, args, { stdio: 'inherit', windowsHide: true });
    active = child;
  
    child.on('error', (err) => {
      if (err.code === 'ENOENT') {
        // The interpreter vanished between probe and launch; fall back rather
        // than die. Clearing active makes this child's later close a no-op.
        active = null;
        launch(index + 1);
      } else {
        console.error(`watermarks-remover: error running ${cmd}: ${err.message}`);
        process.exit(1);
      }
    });
  
    child.on('close', (code) => {
      // Only the selected child may exit the process; a failed candidate that
      // still fires close after an ENOENT error must not kill a fallback.
      if (active === child) process.exit(code ?? 0);
    });
  }
  
  function launch(index) {
    if (index >= candidates.length) {
      const tried = candidates
        .map(([cmd, extra]) => (extra.length ? `${cmd} ${extra.join(' ')}` : cmd))
        .join(', ');
      console.error(
        `watermarks-remover: could not find a working Python 3.10+ interpreter (tried ${tried})`
      );
      process.exit(1);
    }
  
    const [cmd, extraArgs] = candidates[index];
  
    // Probe the candidate: confirm it exists and is at least Python 3.10. Any
    // failure -- a missing binary or an older Python -- falls through to the next
    // candidate.
    execFile(cmd, [...extraArgs, '-c', VERSION_CHECK], (err) => {
      if (err) {
        launch(index + 1);
      } else {
        run(cmd, extraArgs, index);
      }
    });
  }
  
  launch(0);
  

Read the script before you install anything that runs on your machine. This is the one part of a plugin that acts without being asked.