bpo-29958: Minor improvements to zipfile and tarfile CLI. (#944)

1 files changed, 6 insertions, 9 deletions

diff --git a/Lib/tarfile.py b/Lib/tarfile.py
index 2d702dd..9d46e5f 100755
--- a/Lib/tarfile.py
+++ b/Lib/tarfile.py
@@ -2450,11 +2450,11 @@ open = TarFile.open
 def main():
     import argparse
 
-    description = 'A simple command line interface for tarfile module.'
+    description = 'A simple command-line interface for tarfile module.'
     parser = argparse.ArgumentParser(description=description)
     parser.add_argument('-v', '--verbose', action='store_true', default=False,
                         help='Verbose output')
-    group = parser.add_mutually_exclusive_group()
+    group = parser.add_mutually_exclusive_group(required=True)
     group.add_argument('-l', '--list', metavar='<tarfile>',
                        help='Show listing of a tarfile')
     group.add_argument('-e', '--extract', nargs='+',
@@ -2467,7 +2467,7 @@ def main():
                        help='Test if a tarfile is valid')
     args = parser.parse_args()
 
-    if args.test:
+    if args.test is not None:
         src = args.test
         if is_tarfile(src):
             with open(src, 'r') as tar:
@@ -2478,7 +2478,7 @@ def main():
         else:
             parser.exit(1, '{!r} is not a tar archive.\n'.format(src))
 
-    elif args.list:
+    elif args.list is not None:
         src = args.list
         if is_tarfile(src):
             with TarFile.open(src, 'r:*') as tf:
@@ -2486,7 +2486,7 @@ def main():
         else:
             parser.exit(1, '{!r} is not a tar archive.\n'.format(src))
 
-    elif args.extract:
+    elif args.extract is not None:
         if len(args.extract) == 1:
             src = args.extract[0]
             curdir = os.curdir
@@ -2508,7 +2508,7 @@ def main():
         else:
             parser.exit(1, '{!r} is not a tar archive.\n'.format(src))
 
-    elif args.create:
+    elif args.create is not None:
         tar_name = args.create.pop(0)
         _, ext = os.path.splitext(tar_name)
         compressions = {
@@ -2534,8 +2534,5 @@ def main():
         if args.verbose:
             print('{!r} file created.'.format(tar_name))
 
-    else:
-        parser.exit(1, parser.format_help())
-
 if __name__ == '__main__':
     main()