GH-139862: Fix direct instantiation of HelpFormatter (#142384)

Author: savannahostrowski

Lib/argparse.py

@@ -189,6 +189,8 @@ def __init__(
         self._whitespace_matcher = _re.compile(r'\s+', _re.ASCII)
         self._long_break_matcher = _re.compile(r'\n\n\n+')
 
+        self._set_color(False)
+
     def _set_color(self, color):
         from _colorize import can_colorize, decolor, get_theme
 

Lib/test/test_argparse.py

@@ -5694,6 +5694,11 @@ def custom_formatter(prog):
                 a-very-long-command  command that does something
         '''))
 
+    def test_direct_formatter_instantiation(self):
+        formatter = argparse.HelpFormatter(prog="program")
+        formatter.add_usage(usage=None, actions=[], groups=[])
+        help_text = formatter.format_help()
+        self.assertEqual(help_text, "usage: program\n")
 
 # =====================================
 # Optional/Positional constructor tests