py3: partially fix pager spawning on Windows Previously, spinning up the pager crashed because the command and environment was in bytes. (See also 543a788eea2d.) Now it aborts with an invalid handle: $ HGMODULEPOLICY=py py -3 ../hg --traceback --config extensions.evolve=! Traceback (most recent call last): File "c:\Users\Matt\projects\hg\mercurial\ui.py", line 967, in _write self.fout.write(''.join(msgs)) File "c:\Users\Matt\projects\hg\mercurial\windows.py", line 173, in write self.fp.write(s[start:end]) OSError: [WinError 6] The handle is invalid During handling of the above exception, another exception occurred: Traceback (most recent call last): File "c:\Users\Matt\projects\hg\mercurial\scmutil.py", line 164, in callcatch return func() File "c:\Users\Matt\projects\hg\mercurial\dispatch.py", line 350, in _runcatchfunc return _dispatch(req) File "c:\Users\Matt\projects\hg\mercurial\dispatch.py", line 930, in _dispatch return commands.help_(ui, 'shortlist') File "c:\Users\Matt\projects\hg\mercurial\commands.py", line 2930, in help_ ui.write(formatted) File "c:\Users\Matt\projects\hg\mercurial\ui.py", line 948, in write self._writenobuf(*args, **opts) File "c:\Users\Matt\projects\hg\mercurial\ui.py", line 960, in _writenobuf self._write(*msgs, **opts) File "c:\Users\Matt\projects\hg\mercurial\ui.py", line 969, in _write raise error.StdioError(err) mercurial.error.StdioError: [Errno 9] The handle is invalid abort: The handle is invalid The interesting bit here is that the abort message is marked with ANSI color, but the OSError is not.