comparison mercurial/ui.py @ 43377:aaa046919043 stable

ui: flush before prompting for input with readline

I was using `hg absorb` with Python 3 and noticed that the
prompt was appearing without any output about what would be
done. After I answered the prompt, the output was printed
to stdout.

This appears to be a buffering difference between Python 2
and Python 3.

To work around it, this commit adds an explicit flush() before
calling the raw input function when readline is used.

43376:b27cf9f52194

        # prompt ' ' must exist; otherwise readline may delete entire line
        # - http://bugs.python.org/issue12833
        with self.timeblockedsection(b'stdio'):
            if usereadline:
                prompt = encoding.strfromlocal(prompt)
                line = encoding.strtolocal(pycompat.rawinput(prompt))
                # When stdin is in binary mode on Windows, it can cause
                # raw_input() to emit an extra trailing carriage return
                if pycompat.oslinesep == b'\r\n' and line.endswith(b'\r'):

43377:aaa046919043

        # prompt ' ' must exist; otherwise readline may delete entire line
        # - http://bugs.python.org/issue12833
        with self.timeblockedsection(b'stdio'):
            if usereadline:
                self.flush()
                prompt = encoding.strfromlocal(prompt)
                line = encoding.strtolocal(pycompat.rawinput(prompt))
                # When stdin is in binary mode on Windows, it can cause
                # raw_input() to emit an extra trailing carriage return
                if pycompat.oslinesep == b'\r\n' and line.endswith(b'\r'):