Also quote arguments containing :&<>^| on Windows

Author: jhohm

Lib/subprocess.py

@@ -618,7 +618,7 @@ def list2cmdline(seq):
         if result:
             result.append(' ')
 
-        needquote = (" " in arg) or ("\t" in arg) or not arg
+        needquote = not arg or not set(" \t:&<>^|").isdisjoint(arg)
         if needquote:
             result.append('"')
 

Lib/test/test_subprocess.py

@@ -3560,6 +3560,15 @@ def test_invalid_args(self):
                            "import sys; sys.exit(47)"],
                           preexec_fn=lambda: 1)
 
+    def test_args_quoting(self):
+        with tempfile.NamedTemporaryFile(suffix=".bat", delete_on_close=False) as f:
+            f.write(b"echo %*\n")
+            f.close()
+            p = subprocess.run([f.file.name, "a b", "", "c<>d", "e"],
+                               capture_output=True)
+            self.assertEqual(p.returncode, 0, p.stderr)
+            self.assertEndsWith(p.stdout.strip(), b'"a b" "" "c<>d" e')
+
     @support.cpython_only
     def test_issue31471(self):
         # There shouldn't be an assertion failure in Popen() in case the env

Misc/NEWS.d/next/Windows/2025-05-22-16-36-52.gh-issue-133545.YHvz8H.rst

@@ -0,0 +1,2 @@
+In addition to space, tab, and empty string, quote arguments containing
+``:&<>^|`` on Windows. Patch by John Keith Hohm.