[pre-commit] now also checks for broken symlnks

hooks/pre-commit.d/02-detect-broken-symlinks.py

+#!/usr/bin/env python3
+""" Recursively walk the current working directory looking for broken
+symlinks. If any broken symlinks are found print out a report and exit
+with status 1. If none are found exit with status 0.
+
+"""
+import sys
+import os
+
+def _target(path):
+    """Resolve relative symlinks"""
+    try:
+        from pathlib import Path
+        return Path(path).resolve()
+    except ImportError:
+        pass
+    target_path = os.readlink(path)
+    if not os.path.isabs(target_path):
+        target_path = os.path.join(os.path.dirname(path),target_path)
+    return str(target_path)
+
+broken = []
+for root, dirs, files in os.walk('.'):
+    if root.startswith('./.git'):
+        # Ignore the .git directory.
+        continue
+    for filename in files:
+        path = os.path.join(root,filename)
+        if os.path.islink(path):
+            target_path = _target(path)
+            if not os.path.exists(target_path):
+                broken.append('{} --> {}'.format(path, target_path))
+        else:
+            # If it's not a symlink we're not interested.
+            continue
+
+if len(broken) == 0:
+    sys.exit(0)
+
+print('\nbroken symlink(s) found: {}'.format('\n'.join(broken)), file=sys.stderr)
+sys.exit(1)