tools: Fix ANSI color converter on Windows

Fix a regression of b77addea2fc44d1a336070e156d1c4deb50f752e: The ANSI
color converter returns a class on Windows instead of an object so its
methods won't be callable and will result in a not so helpful error
message: "idf_monitor failed with exit code 120"

tools/idf_monitor.py

@@ -73,7 +73,7 @@ import tempfile
 import serial
 import serial.tools.list_ports
 # Windows console stuff
-from idf_monitor_base.ansi_color_convertor import ANSIColorConverter
+from idf_monitor_base.ansi_color_converter import get_converter
 
 key_description = miniterm.key_description
 
@@ -101,9 +101,9 @@ class Monitor(object):
         self.console = miniterm.Console()
         self.enable_address_decoding = enable_address_decoding
 
-        sys.stderr = ANSIColorConverter(sys.stderr, decode_output=True)
-        self.console.output = ANSIColorConverter(self.console.output)
-        self.console.byte_output = ANSIColorConverter(self.console.byte_output)
+        sys.stderr = get_converter(sys.stderr, decode_output=True)
+        self.console.output = get_converter(self.console.output)
+        self.console.byte_output = get_converter(self.console.byte_output)
 
         socket_mode = serial_instance.port.startswith(
             'socket://')  # testing hook - data from serial can make exit the monitor

tools/idf_monitor_base/ansi_color_converter.py

@@ -17,7 +17,11 @@ import os
 import re
 import sys
 from io import TextIOBase
-from typing import Union
+
+try:
+    from typing import Optional, Union
+except ImportError:
+    pass
 
 from .output_helpers import ANSI_NORMAL
 
@@ -39,6 +43,17 @@ if os.name == 'nt':
     SetConsoleTextAttribute = ctypes.windll.kernel32.SetConsoleTextAttribute  # type: ignore
 
 
+def get_converter(orig_output_method=None, decode_output=False):
+    # type: (Optional[TextIOBase], bool) -> Union[ANSIColorConverter, Optional[TextIOBase]]
+    """
+    Returns an ANSIColorConverter on Windows and the original output method (orig_output_method) on other platforms.
+    The ANSIColorConverter with decode_output=True will decode the bytes before passing them to the output.
+    """
+    if os.name == 'nt':
+        return ANSIColorConverter(orig_output_method, decode_output)
+    return orig_output_method
+
+
 class ANSIColorConverter(object):
     """Class to wrap a file-like output stream, intercept ANSI color codes,
     and convert them into calls to Windows SetConsoleTextAttribute.
@@ -50,11 +65,6 @@ class ANSIColorConverter(object):
     least-bad working solution, as winpty doesn't support any "passthrough" mode for raw output.
     """
 
-    def __new__(cls, output=None, decode_output=False):  # type: ignore  # noqa
-        if os.name == 'nt':
-            return cls
-        return output
-
     def __init__(self, output=None, decode_output=False):
         # type: (TextIOBase, bool) -> None
         self.output = output