GeezerVison

Older macOS reports a variation selector as a spacing character (wcwidth() returns 1) instead of a zero-width combining mark, so curses cannot place it in the same cell as its base character and test_addch_emoji raises ValueError.
curses groups cells by wcwidth(), the same as ncurses, so the assertion is only valid where the platform reports the selector as zero-width; skip it elsewhere.

The failure is confirmed on macOS 14.2 (reported in the issue) and gone by macOS 26, which CI runs, so 26 is the conservative cutoff.

🤖 Generated with Claude Code

• Issue: Add wide-character (cchar_t) support to the curses module #151757