Modernize batch_file_rename with pathlib and add dry-run feature

Author: SantanDon

batch_file_rename.py

@@ -1,57 +1,63 @@
-# batch_file_rename.py
-# Created: 6th August 2012
-
-"""
-This will batch rename a group of files in a given directory,
-once you pass the current and new extensions
-"""
-
-# just checking
-__author__ = "Craig Richards"
-__version__ = "1.0"
-
 import argparse
 import os
+from pathlib import Path
 
 
-def batch_rename(work_dir, old_ext, new_ext):
+def batch_rename(work_dir, old_ext, new_ext, dry_run=False):
     """
     This will batch rename a group of files in a given directory,
     once you pass the current and new extensions
     """
-    # files = os.listdir(work_dir)
-    for filename in os.listdir(work_dir):
-        # Get the file extension
-        split_file = os.path.splitext(filename)
-        # Unpack tuple element
-        root_name, file_ext = split_file
-        # Start of the logic to check the file extensions, if old_ext = file_ext
-        if old_ext == file_ext:
-            # Returns changed name of the file with new extention
-            newfile = root_name + new_ext
+    work_path = Path(work_dir)
+    if not work_path.is_dir():
+        print(f"Error: {work_dir} is not a valid directory.")
+        return
+
+    print(f"[*] Scanning {work_dir} for files with extension '{old_ext}'...")
+    
+    found_files = list(work_path.glob(f"*{old_ext}"))
+    if not found_files:
+        print(f"[!] No files found with extension '{old_ext}'.")
+        return
 
-            # Write the files
-            os.rename(os.path.join(work_dir, filename), os.path.join(work_dir, newfile))
-    print("rename is done!")
-    print(os.listdir(work_dir))
+    for file_path in found_files:
+        new_file_path = file_path.with_suffix(new_ext)
+        
+        if new_file_path.exists():
+            print(f"[!] Skip: {new_file_path.name} already exists. Cannot rename {file_path.name}.")
+            continue
+
+        if dry_run:
+            print(f"[DRY-RUN] Would rename: {file_path.name} -> {new_file_path.name}")
+        else:
+            try:
+                file_path.rename(new_file_path)
+                print(f"[+] Renamed: {file_path.name} -> {new_file_path.name}")
+            except Exception as e:
+                print(f"[!] Error renaming {file_path.name}: {e}")
+
+    if not dry_run:
+        print("[*] Batch rename completed.")
 
 
 def get_parser():
     parser = argparse.ArgumentParser(
-        description="change extension of files in a working directory"
+        description="Change extension of files in a working directory"
     )
     parser.add_argument(
         "work_dir",
-        metavar="WORK_DIR",
-        type=str,
-        nargs=1,
-        help="the directory where to change extension",
+        help="The directory where to change extension",
+    )
+    parser.add_argument(
+        "old_ext", help="Old extension (e.g., .txt or txt)"
     )
     parser.add_argument(
-        "old_ext", metavar="OLD_EXT", type=str, nargs=1, help="old extension"
+        "new_ext", help="New extension (e.g., .md or md)"
     )
     parser.add_argument(
-        "new_ext", metavar="NEW_EXT", type=str, nargs=1, help="new extension"
+        "--dry-run",
+        action="store_true",
+        help="Preview changes without applying them",
     )
     return parser
 
@@ -60,22 +66,14 @@ def main():
     """
     This will be called if the script is directly invoked.
     """
-    # adding command line argument
     parser = get_parser()
-    args = vars(parser.parse_args())
+    args = parser.parse_args()
 
-    # Set the variable work_dir with the first argument passed
-    work_dir = args["work_dir"][0]
-    # Set the variable old_ext with the second argument passed
-    old_ext = args["old_ext"][0]
-    if old_ext and old_ext[0] != ".":
-        old_ext = "." + old_ext
-    # Set the variable new_ext with the third argument passed
-    new_ext = args["new_ext"][0]
-    if new_ext and new_ext[0] != ".":
-        new_ext = "." + new_ext
+    work_dir = args.work_dir
+    old_ext = args.old_ext if args.old_ext.startswith(".") else "." + args.old_ext
+    new_ext = args.new_ext if args.new_ext.startswith(".") else "." + args.new_ext
 
-    batch_rename(work_dir, old_ext, new_ext)
+    batch_rename(work_dir, old_ext, new_ext, dry_run=args.dry_run)
 
 
 if __name__ == "__main__":