Merge pull request #22 from guykisel/check-case-conflict

Add check_case_conflict hook

pre_commit_hooks/check_added_large_files.py

@@ -8,15 +8,13 @@ import math
 import os
 import sys
 
-from plumbum import local
+from pre_commit_hooks.util import added_files
 
 
 def find_large_added_files(filenames, maxkb):
     # Find all added files that are also in the list of files pre-commit tells
     # us about
-    filenames = set(local['git'](
-        'diff', '--staged', '--name-only', '--diff-filter', 'A',
-    ).splitlines()) & set(filenames)
+    filenames = added_files() & set(filenames)
 
     retv = 0
     for filename in filenames:

pre_commit_hooks/check_case_conflict.py

@@ -0,0 +1,58 @@
+from __future__ import absolute_import
+from __future__ import print_function
+from __future__ import unicode_literals
+
+import argparse
+
+from plumbum import local
+
+from pre_commit_hooks.util import added_files
+
+
+def lower_set(iterable):
+    return set(x.lower() for x in iterable)
+
+
+def find_conflicting_filenames(filenames):
+    repo_files = set(local['git']('ls-files').splitlines())
+    relevant_files = set(filenames) | added_files()
+    repo_files -= relevant_files
+    retv = 0
+
+    # new file conflicts with existing file
+    conflicts = lower_set(repo_files) & lower_set(relevant_files)
+
+    # new file conflicts with other new file
+    lowercase_relevant_files = lower_set(relevant_files)
+    for filename in set(relevant_files):
+        if filename.lower() in lowercase_relevant_files:
+            lowercase_relevant_files.remove(filename.lower())
+        else:
+            conflicts.add(filename.lower())
+
+    if conflicts:
+        conflicting_files = [
+            x for x in repo_files | relevant_files
+            if x.lower() in conflicts
+        ]
+        for filename in sorted(conflicting_files):
+            print('Case-insensitivity conflict found: {0}'.format(filename))
+        retv = 1
+
+    return retv
+
+
+def main(argv=None):
+    parser = argparse.ArgumentParser()
+    parser.add_argument(
+        'filenames', nargs='*',
+        help='Filenames pre-commit believes are changed.'
+    )
+
+    args = parser.parse_args(argv)
+
+    return find_conflicting_filenames(args.filenames)
+
+
+if __name__ == '__main__':
+    exit(main())

pre_commit_hooks/util.py

@@ -0,0 +1,11 @@
+from __future__ import absolute_import
+from __future__ import print_function
+from __future__ import unicode_literals
+
+from plumbum import local
+
+
+def added_files():
+    return set(local['git'](
+        'diff', '--staged', '--name-only', '--diff-filter', 'A',
+    ).splitlines())