Bug description:
curses.LINES, curses.COLS, curses.COLORS and curses.COLOR_PAIRS are copied into the module namespace when a terminal is initialized, and set_term() does not refresh them, so after a switch they describe a different terminal. curses.newwin(curses.LINES, curses.COLS) then sizes a window for the wrong screen, and a colour checked against curses.COLORS is rejected by init_pair(). screen.use() behaves the same way.
import curses, fcntl, os, struct, termios
def screen(kind, rows, cols):
slave = os.openpty()[1]
fcntl.ioctl(slave, termios.TIOCSWINSZ, struct.pack('HHHH', rows, cols, 0, 0))
return curses.newterm(kind, slave, slave)
small = screen('xterm', 18, 60) # 8 colours
curses.start_color()
big = screen('xterm-256color', 32, 120) # 256 colours
curses.start_color()
curses.set_term(small)
print('current screen', small.stdscr.getmaxyx(), curses.ncurses_version)
print('LINES, COLS ', (curses.LINES, curses.COLS))
print('COLORS ', curses.COLORS)
try:
curses.init_pair(1, curses.COLORS - 1, 0)
except ValueError as exc:
print('init_pair ', exc)$ ./python repro.py
current screen (18, 60) curses.ncurses_version(major=6, minor=6, patch=20251231)
LINES, COLS (32, 120)
COLORS 256
init_pair Color number is greater than COLORS-1 (7).
Expected: (18, 60) and 8, the values of the screen that is current. Doc/library/curses.rst calls LINES "the height of the screen" and COLORS "the maximum number of colors the terminal can support", with nothing about them following one screen only.
set_term() does call the internal update_lines_cols(), but that helper re-reads the ncurses LINES/COLS globals, which set_term() leaves alone, and nothing copies COLORS/COLOR_PAIRS, whose C value did change.
CPython versions tested on:
CPython main branch
Operating systems tested on:
Linux
Linked PRs
Bug description:
curses.LINES,curses.COLS,curses.COLORSandcurses.COLOR_PAIRSare copied into the module namespace when a terminal is initialized, andset_term()does not refresh them, so after a switch they describe a different terminal.curses.newwin(curses.LINES, curses.COLS)then sizes a window for the wrong screen, and a colour checked againstcurses.COLORSis rejected byinit_pair().screen.use()behaves the same way.Expected:
(18, 60)and8, the values of the screen that is current.Doc/library/curses.rstcallsLINES"the height of the screen" andCOLORS"the maximum number of colors the terminal can support", with nothing about them following one screen only.set_term()does call the internalupdate_lines_cols(), but that helper re-reads the ncursesLINES/COLSglobals, whichset_term()leaves alone, and nothing copiesCOLORS/COLOR_PAIRS, whose C value did change.CPython versions tested on:
CPython main branch
Operating systems tested on:
Linux
Linked PRs