gh-85567: Fix resouce warnings in pickle and pickletools CLIs (GH-113618)

Explicitly open and close files instead of using FileType.

Lib/pickle.py

@@ -1793,7 +1793,7 @@ def _test():
     parser = argparse.ArgumentParser(
         description='display contents of the pickle files')
     parser.add_argument(
-        'pickle_file', type=argparse.FileType('br'),
+        'pickle_file',
         nargs='*', help='the pickle file')
     parser.add_argument(
         '-t', '--test', action='store_true',
@@ -1809,6 +1809,10 @@ def _test():
             parser.print_help()
         else:
             import pprint
-            for f in args.pickle_file:
-                obj = load(f)
+            for fn in args.pickle_file:
+                if fn == '-':
+                    obj = load(sys.stdin.buffer)
+                else:
+                    with open(fn, 'rb') as f:
+                        obj = load(f)
                 pprint.pprint(obj)

Lib/pickletools.py

@@ -2848,10 +2848,10 @@ def _test():
     parser = argparse.ArgumentParser(
         description='disassemble one or more pickle files')
     parser.add_argument(
-        'pickle_file', type=argparse.FileType('br'),
+        'pickle_file',
         nargs='*', help='the pickle file')
     parser.add_argument(
-        '-o', '--output', default=sys.stdout, type=argparse.FileType('w'),
+        '-o', '--output',
         help='the file where the output should be written')
     parser.add_argument(
         '-m', '--memo', action='store_true',
@@ -2876,15 +2876,26 @@ def _test():
     if args.test:
         _test()
     else:
-        annotate = 30 if args.annotate else 0
         if not args.pickle_file:
             parser.print_help()
-        elif len(args.pickle_file) == 1:
-            dis(args.pickle_file[0], args.output, None,
-                args.indentlevel, annotate)
         else:
+            annotate = 30 if args.annotate else 0
             memo = {} if args.memo else None
-            for f in args.pickle_file:
-                preamble = args.preamble.format(name=f.name)
-                args.output.write(preamble + '\n')
-                dis(f, args.output, memo, args.indentlevel, annotate)
+            if args.output is None:
+                output = sys.stdout
+            else:
+                output = open(args.output, 'w')
+            try:
+                for arg in args.pickle_file:
+                    if len(args.pickle_file) > 1:
+                        name = '<stdin>' if arg == '-' else arg
+                        preamble = args.preamble.format(name=name)
+                        output.write(preamble + '\n')
+                    if arg == '-':
+                        dis(sys.stdin.buffer, output, memo, args.indentlevel, annotate)
+                    else:
+                        with open(arg, 'rb') as f:
+                            dis(f, output, memo, args.indentlevel, annotate)
+            finally:
+                if output is not sys.stdout:
+                    output.close()

Misc/NEWS.d/next/Library/2024-01-01-13-26-02.gh-issue-85567.K4U15m.rst

@@ -0,0 +1,2 @@
+Fix resource warnings for unclosed files in :mod:`pickle` and
+:mod:`pickletools` command line interfaces.