1 files changed, 8 insertions, 84 deletions
diff --git a/Lib/fontTools/ufoLib/filenames.py b/Lib/fontTools/ufoLib/filenames.py
index baf22076..2815469f 100644
--- a/Lib/fontTools/ufoLib/filenames.py
+++ b/Lib/fontTools/ufoLib/filenames.py
@@ -3,88 +3,11 @@ User name to file name conversion.
 This was taken from the UFO 3 spec.
 """
 
-# Restrictions are taken mostly from
-# https://docs.microsoft.com/en-gb/windows/win32/fileio/naming-a-file#naming-conventions.
-#
-# 1. Integer value zero, sometimes referred to as the ASCII NUL character.
-# 2. Characters whose integer representations are in the range 1 to 31,
-#    inclusive.
-# 3. Various characters that (mostly) Windows and POSIX-y filesystems don't
-#    allow, plus "(" and ")", as per the specification.
-illegalCharacters = {
-    "\x00",
-    "\x01",
-    "\x02",
-    "\x03",
-    "\x04",
-    "\x05",
-    "\x06",
-    "\x07",
-    "\x08",
-    "\t",
-    "\n",
-    "\x0b",
-    "\x0c",
-    "\r",
-    "\x0e",
-    "\x0f",
-    "\x10",
-    "\x11",
-    "\x12",
-    "\x13",
-    "\x14",
-    "\x15",
-    "\x16",
-    "\x17",
-    "\x18",
-    "\x19",
-    "\x1a",
-    "\x1b",
-    "\x1c",
-    "\x1d",
-    "\x1e",
-    "\x1f",
-    '"',
-    "*",
-    "+",
-    "/",
-    ":",
-    "<",
-    ">",
-    "?",
-    "[",
-    "\\",
-    "]",
-    "(",
-    ")",
-    "|",
-    "\x7f",
-}
-reservedFileNames = {
-    "aux",
-    "clock$",
-    "com1",
-    "com2",
-    "com3",
-    "com4",
-    "com5",
-    "com6",
-    "com7",
-    "com8",
-    "com9",
-    "con",
-    "lpt1",
-    "lpt2",
-    "lpt3",
-    "lpt4",
-    "lpt5",
-    "lpt6",
-    "lpt7",
-    "lpt8",
-    "lpt9",
-    "nul",
-    "prn",
-}
+illegalCharacters = r"\" * + / : < > ? [ \ ] | \0".split(" ")
+illegalCharacters += [chr(i) for i in range(1, 32)]
+illegalCharacters += [chr(0x7F)]
+reservedFileNames = "CON PRN AUX CLOCK$ NUL A:-Z: COM1".lower().split(" ")
+reservedFileNames += "LPT1 LPT2 LPT3 COM2 COM3 COM4".lower().split(" ")
 maxFileNameLength = 255
 
 
@@ -92,9 +15,10 @@ class NameTranslationError(Exception):
 	pass
 
 
-def userNameToFileName(userName: str, existing=(), prefix="", suffix=""):
+def userNameToFileName(userName: str, existing=[], prefix="", suffix=""):
 	"""
-	`existing` should be a set-like object.
+	existing should be a case-insensitive list
+	of all existing file names.
 
 	>>> userNameToFileName("a") == "a"
 	True