OpenHome/venv/Lib/site-packages/_pytest/_io/wcwidth.py

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2021-07-21 21:33:05 +02:00
import unicodedata
from functools import lru_cache
@lru_cache(100)
def wcwidth(c: str) -> int:
"""Determine how many columns are needed to display a character in a terminal.
Returns -1 if the character is not printable.
Returns 0, 1 or 2 for other characters.
"""
o = ord(c)
# ASCII fast path.
if 0x20 <= o < 0x07F:
return 1
# Some Cf/Zp/Zl characters which should be zero-width.
if (
o == 0x0000
or 0x200B <= o <= 0x200F
or 0x2028 <= o <= 0x202E
or 0x2060 <= o <= 0x2063
):
return 0
category = unicodedata.category(c)
# Control characters.
if category == "Cc":
return -1
# Combining characters with zero width.
if category in ("Me", "Mn"):
return 0
# Full/Wide east asian characters.
if unicodedata.east_asian_width(c) in ("F", "W"):
return 2
return 1
def wcswidth(s: str) -> int:
"""Determine how many columns are needed to display a string in a terminal.
Returns -1 if the string contains non-printable characters.
"""
width = 0
for c in unicodedata.normalize("NFC", s):
wc = wcwidth(c)
if wc < 0:
return -1
width += wc
return width