comparison mercurial/color.py @ 31499:31d2ddfd338c

color: sync text attributes and buffered text output on Windows (issue5508)

I originally noticed that log output wasn't being colored after 3a4c0905f357,
but there were other complications too.  With a bunch of untracked files, only
the first 1K of characters were colored pink, and the rest were normal white.  A
single modified file at the top would also be colored pink.

Line buffering and full buffering are treated as the same thing in Windows [1],
meaning the stream is either buffered or not.  I can't find any explicit
documentation to say stdout is unbuffered by default when attached to a console
(but some internet postings indicated that is the case[2]).  Therefore, it seems
that explicit flushes are better than just not reopening stdout.

NB: pager is now on by default, and needs to be disabled to see any color on
Windows.

[1] https://msdn.microsoft.com/en-us/library/86cebhfs(v=vs.140).aspx
[2] https://sourceforge.net/p/mingw/mailman/message/27121137/

31498:a248bbfa0bc7

        try:
            while m:
                for sattr in m.group(1).split(';'):
                    if sattr:
                        attr = mapcolor(int(sattr), attr)
                _kernel32.SetConsoleTextAttribute(stdout, attr)
                writefunc(m.group(2), **opts)
                m = re.match(ansire, m.group(3))
        finally:
            # Explicitly reset original attributes
            _kernel32.SetConsoleTextAttribute(stdout, origattr)

31499:31d2ddfd338c

        try:
            while m:
                for sattr in m.group(1).split(';'):
                    if sattr:
                        attr = mapcolor(int(sattr), attr)
                ui.flush()
                _kernel32.SetConsoleTextAttribute(stdout, attr)
                writefunc(m.group(2), **opts)
                m = re.match(ansire, m.group(3))
        finally:
            # Explicitly reset original attributes
            ui.flush()
            _kernel32.SetConsoleTextAttribute(stdout, origattr)