Make the Python CLI error message style more consistent (GH-128129)

9cel · pull[bot] · commit 111571833d2c · 2025-02-07T18:01:14.000Z
diff --git a/Lib/test/test_cmd_line.py b/Lib/test/test_cmd_line.py
@@ -1012,7 +1012,7 @@ def test_parsing_error(self):
                               stdout=subprocess.PIPE,
                               stderr=subprocess.PIPE,
                               text=True)
-        err_msg = "unknown option --unknown-option\nusage: "
+        err_msg = "Unknown option: --unknown-option\nusage: "
         self.assertTrue(proc.stderr.startswith(err_msg), proc.stderr)
         self.assertNotEqual(proc.returncode, 0)
 
diff --git a/Python/getopt.c b/Python/getopt.c
@@ -102,7 +102,7 @@ int _PyOS_GetOpt(Py_ssize_t argc, wchar_t * const *argv, int *longindex)
         // Parse long option.
         if (*opt_ptr == L'\0') {
             if (_PyOS_opterr) {
-                fprintf(stderr, "expected long option\n");
+                fprintf(stderr, "Expected long option\n");
             }
             return -1;
         }
@@ -114,7 +114,7 @@ int _PyOS_GetOpt(Py_ssize_t argc, wchar_t * const *argv, int *longindex)
         }
         if (!opt->name) {
             if (_PyOS_opterr) {
-                fprintf(stderr, "unknown option %ls\n", argv[_PyOS_optind - 1]);
+                fprintf(stderr, "Unknown option: %ls\n", argv[_PyOS_optind - 1]);
             }
             return '_';
         }

Original file line number	Diff line number	Diff line change
`@@ -102,7 +102,7 @@ int _PyOS_GetOpt(Py_ssize_t argc, wchar_t * const argv, int longindex)`
`102`	`102`	`// Parse long option.`
`103`	`103`	`if (*opt_ptr == L'\0') {`
`104`	`104`	`if (_PyOS_opterr) {`
`105`		`- fprintf(stderr, "expected long option\n");`
	`105`	`+ fprintf(stderr, "Expected long option\n");`
`106`	`106`	`}`
`107`	`107`	`return -1;`
`108`	`108`	`}`
`@@ -114,7 +114,7 @@ int _PyOS_GetOpt(Py_ssize_t argc, wchar_t * const argv, int longindex)`
`114`	`114`	`}`
`115`	`115`	`if (!opt->name) {`
`116`	`116`	`if (_PyOS_opterr) {`
`117`		`- fprintf(stderr, "unknown option %ls\n", argv[_PyOS_optind - 1]);`
	`117`	`+ fprintf(stderr, "Unknown option: %ls\n", argv[_PyOS_optind - 1]);`
`118`	`118`	`}`
`119`	`119`	`return '_';`
`120`	`120`	`}`