Partial backport of #11785

Author: Ivan Levkivskyi

mypy/typeshed/stdlib/_curses.pyi

@@ -344,7 +344,7 @@ def termattrs() -> int: ...
 def termname() -> bytes: ...
 def tigetflag(__capname: str) -> int: ...
 def tigetnum(__capname: str) -> int: ...
-def tigetstr(__capname: str) -> bytes: ...
+def tigetstr(__capname: str) -> bytes | None: ...
 def tparm(
     __str: bytes,
     __i1: int = ...,

mypy/util.py

@@ -566,11 +566,12 @@ def initialize_unix_colors(self) -> bool:
         under = curses.tigetstr('smul')
         set_color = curses.tigetstr('setaf')
         set_eseq = curses.tigetstr('cup')
+        normal = curses.tigetstr('sgr0')
 
-        if not (bold and under and set_color and set_eseq):
+        if not (bold and under and set_color and set_eseq and normal):
             return False
 
-        self.NORMAL = curses.tigetstr('sgr0').decode()
+        self.NORMAL = normal.decode()
         self.BOLD = bold.decode()
         self.UNDER = under.decode()
         self.DIM = parse_gray_color(set_eseq)