[BUG] Long unicode (emojis) get wrong length calculated

[manuelF]

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Describe the bug Using emojis (on terminals that support it) misaligns the windows due to wrong length computed (byte length vs rune length)

To Reproduce

Taking emojis from the https://en.wikipedia.org/wiki/X_mark:

import pytermgui as ptg

with ptg.WindowManager() as manager:
    manager.add(ptg.Window(
        ptg.Label("NormalLabel"),
        ptg.Label("1x Emoji Label: ❌"),
        ptg.Label("2x Emoji Label: ❌❌"),
        ptg.Label("3x Emoji Label: ❌❌❌"),
        ptg.Label("1x Normal Label: X"),
        ptg.Label("2x Normal Label: X X"),
        ptg.Label("3x Normal Label: X X X"),
    ))

Expected behavior A normal outer box.

Seen behaviour* Boxes with emojis on the line are offset, due to printing chars differently.

╔══════════════════════════════════════╗
║              NormalLabel             ║
║           1x Emoji Label: ❌          ║
║          2x Emoji Label: ❌❌          ║
║          3x Emoji Label: ❌❌❌         ║
║          1x Normal Label: X          ║
║         2x Normal Label: X X         ║
║        3x Normal Label: X X X        ║

System information

$ ptg --version

PyTermGUI version 7.4.0

System details:
    Python version: 3.8.10
    $TERM:          xterm-256color
    $COLORTERM:     None
    Color support:  ColorSystem.EIGHT_BIT
    OS Platform:    Linux-5.15.90.1-microsoft-standard-WSL2-x86_64-with-glibc2.29$ ptg --version

Possible cause Possible incorrect way of computing real_length with wide-characters.

https://github.com/bczsalba/pytermgui/blob/56b2cc1dc74ada438088719d2ebe95e21d509ad6/pytermgui/widgets/base.py#L781

Possible solution See alternatives like: https://stackoverflow.com/a/30775818

Maybe?

Thanks!

[manuelF]

Note that the fix provided in PR#118 (after being modified to include both sets of chars) displays correctly. https://github.com/bczsalba/pytermgui/pull/118

RE_CHINESE = re.compile(r"[\u4e00-\u9fff]")
RE_EMOJI = re.compile(r"[\u2000-\u2fff]")

[...]

@lru_cache(maxsize=None)
def real_length(text: str) -> int:
    if bool(RE_CHINESE.search(text)) or bool(RE_EMOJI.search(text)):
        return sum(wcswidth(c) for c in strip_ansi(text))    
    return len(strip_ansi(text))