procutil: make stream detection in make_line_buffered more correct and strict
In make_line_buffered(), we don’t want to wrap the stream if we know that lines
get flushed to the underlying raw stream already.
Previously, the heuristic was too optimistic. It assumed that any stream which
is not an instance of io.BufferedIOBase doesn’t need wrapping. However, there
are buffered streams that aren’t instances of io.BufferedIOBase, like
Mercurial’s own winstdout.
The new logic is different in two ways:
First, only for the check, if unwraps any combination of WriteAllWrapper and
winstdout.
Second, it skips wrapping the stream only if it is an instance of io.RawIOBase
(or already wrapped). If it is an instance of io.BufferedIOBase, it gets
wrapped. In any other case, the function raises an exception. This ensures
that, if an unknown stream is passed or we add another wrapper in the future,
we don’t wrap the stream if it’s already line buffered or not wrap the stream
if it’s not line buffered. In fact, this was already helpful during development
of this change. Without it, I possibly would have forgot that WriteAllWrapper
needs to be ignored for the check, leading to unnecessary wrapping if stdout is
unbuffered.
The alternative would have been to always wrap unknown streams. However, I
don’t think that anyone would benefit from being less strict. We can expect
streams from the standard library to be subclassing either io.RawIOBase or
io.BufferedIOBase, so running Mercurial in the standard way should not regress
by this change. Py2exe might replace sys.stdout and sys.stderr, but that
currently breaks Mercurial anyway and also these streams don’t claim to be
interactive, so this function is not called for them.
Test text wrapping for multibyte characters
$ mkdir t
$ cd t
define commands to display help text
$ cat << EOF > show.py
> from mercurial import registrar
>
> cmdtable = {}
> command = registrar.command(cmdtable)
>
> # Japanese full-width characters:
> @command(b'show_full_ja', [], '')
> def show_full_ja(ui, **opts):
> u'''\u3042\u3044\u3046\u3048\u304a\u304b\u304d\u304f\u3051 \u3042\u3044\u3046\u3048\u304a\u304b\u304d\u304f\u3051 \u3042\u3044\u3046\u3048\u304a\u304b\u304d\u304f\u3051
>
> \u3042\u3044\u3046\u3048\u304a\u304b\u304d\u304f\u3051 \u3042\u3044\u3046\u3048\u304a\u304b\u304d\u304f\u3051 \u3042\u3044\u3046\u3048\u304a\u304b\u304d\u304f\u3051 \u3042\u3044\u3046\u3048\u304a\u304b\u304d\u304f\u3051
>
> \u3042\u3044\u3046\u3048\u304a\u304b\u304d\u304f\u3051\u3042\u3044\u3046\u3048\u304a\u304b\u304d\u304f\u3051\u3042\u3044\u3046\u3048\u304a\u304b\u304d\u304f\u3051\u3042\u3044\u3046\u3048\u304a\u304b\u304d\u304f\u3051
> '''
>
> # Japanese half-width characters:
> @command(b'show_half_ja', [], '')
> def show_half_ja(ui, *opts):
> u'''\uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79 \uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79 \uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79 \uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79
>
> \uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79 \uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79 \uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79 \uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79 \uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79 \uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79 \uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79 \uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79
>
> \uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79\uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79\uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79\uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79\uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79\uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79\uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79\uff71\uff72\uff73\uff74\uff75\uff76\uff77\uff78\uff79
> '''
>
> # Japanese ambiguous-width characters:
> @command(b'show_ambig_ja', [], '')
> def show_ambig_ja(ui, **opts):
> u'''\u03b1\u03b2\u03b3\u03b4\u03c5\u03b6\u03b7\u03b8\u25cb \u03b1\u03b2\u03b3\u03b4\u03c5\u03b6\u03b7\u03b8\u25cb \u03b1\u03b2\u03b3\u03b4\u03c5\u03b6\u03b7\u03b8\u25cb
>
> \u03b1\u03b2\u03b3\u03b4\u03c5\u03b6\u03b7\u03b8\u25cb \u03b1\u03b2\u03b3\u03b4\u03c5\u03b6\u03b7\u03b8\u25cb \u03b1\u03b2\u03b3\u03b4\u03c5\u03b6\u03b7\u03b8\u25cb \u03b1\u03b2\u03b3\u03b4\u03c5\u03b6\u03b7\u03b8\u25cb \u03b1\u03b2\u03b3\u03b4\u03c5\u03b6\u03b7\u03b8\u25cb \u03b1\u03b2\u03b3\u03b4\u03c5\u03b6\u03b7\u03b8\u25cb \u03b1\u03b2\u03b3\u03b4\u03c5\u03b6\u03b7\u03b8\u25cb
>
> \u03b1\u03b2\u03b3\u03b4\u03c5\u03b6\u03b7\u03b8\u25cb\u03b1\u03b2\u03b3\u03b4\u03c5\u03b6\u03b7\u03b8\u25cb\u03b1\u03b2\u03b3\u03b4\u03c5\u03b6\u03b7\u03b8\u25cb\u03b1\u03b2\u03b3\u03b4\u03c5\u03b6\u03b7\u03b8\u25cb\u03b1\u03b2\u03b3\u03b4\u03c5\u03b6\u03b7\u03b8\u25cb\u03b1\u03b2\u03b3\u03b4\u03c5\u03b6\u03b7\u03b8\u25cb\u03b1\u03b2\u03b3\u03b4\u03c5\u03b6\u03b7\u03b8\u25cb
> '''
>
> # Russian ambiguous-width characters:
> @command(b'show_ambig_ru', [], '')
> def show_ambig_ru(ui, **opts):
> u'''\u041d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0438 \u041d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0438 \u041d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0438 \u041d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0438 \u041d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0438
>
> \u041d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0438 \u041d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0438 \u041d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0438 \u041d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0438 \u041d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0438 \u041d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0438
>
> \u041d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0438\u041d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0438\u041d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0438\u041d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0438\u041d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0438\u041d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0438\u041d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0438
> '''
> EOF
"COLUMNS=60" means that there is no lines which has grater than 58 width
(1) test text wrapping for non-ambiguous-width characters
(1-1) display Japanese full-width characters in cp932
$ COLUMNS=60 hg --encoding cp932 --config extensions.show=./show.py help show_full_ja
hg show_full_ja
\x82\xa0\x82\xa2\x82\xa4\x82\xa6\x82\xa8\x82\xa9\x82\xab\x82\xad\x82\xaf \x82\xa0\x82\xa2\x82\xa4\x82\xa6\x82\xa8\x82\xa9\x82\xab\x82\xad\x82\xaf \x82\xa0\x82\xa2\x82\xa4\x82\xa6\x82\xa8\x82\xa9\x82\xab\x82\xad\x82\xaf (esc)
\x82\xa0\x82\xa2\x82\xa4\x82\xa6\x82\xa8\x82\xa9\x82\xab\x82\xad\x82\xaf \x82\xa0\x82\xa2\x82\xa4\x82\xa6\x82\xa8\x82\xa9\x82\xab\x82\xad\x82\xaf (esc)
\x82\xa0\x82\xa2\x82\xa4\x82\xa6\x82\xa8\x82\xa9\x82\xab\x82\xad\x82\xaf \x82\xa0\x82\xa2\x82\xa4\x82\xa6\x82\xa8\x82\xa9\x82\xab\x82\xad\x82\xaf (esc)
\x82\xa0\x82\xa2\x82\xa4\x82\xa6\x82\xa8\x82\xa9\x82\xab\x82\xad\x82\xaf\x82\xa0\x82\xa2\x82\xa4\x82\xa6\x82\xa8\x82\xa9\x82\xab\x82\xad\x82\xaf\x82\xa0\x82\xa2\x82\xa4\x82\xa6\x82\xa8\x82\xa9\x82\xab\x82\xad\x82\xaf (esc)
\x82\xa0\x82\xa2\x82\xa4\x82\xa6\x82\xa8\x82\xa9\x82\xab\x82\xad\x82\xaf (esc)
(some details hidden, use --verbose to show complete help)
(1-2) display Japanese full-width characters in utf-8
$ COLUMNS=60 hg --encoding utf-8 --config extensions.show=./show.py help show_full_ja
hg show_full_ja
\xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88\xe3\x81\x8a\xe3\x81\x8b\xe3\x81\x8d\xe3\x81\x8f\xe3\x81\x91 \xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88\xe3\x81\x8a\xe3\x81\x8b\xe3\x81\x8d\xe3\x81\x8f\xe3\x81\x91 \xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88\xe3\x81\x8a\xe3\x81\x8b\xe3\x81\x8d\xe3\x81\x8f\xe3\x81\x91 (esc)
\xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88\xe3\x81\x8a\xe3\x81\x8b\xe3\x81\x8d\xe3\x81\x8f\xe3\x81\x91 \xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88\xe3\x81\x8a\xe3\x81\x8b\xe3\x81\x8d\xe3\x81\x8f\xe3\x81\x91 (esc)
\xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88\xe3\x81\x8a\xe3\x81\x8b\xe3\x81\x8d\xe3\x81\x8f\xe3\x81\x91 \xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88\xe3\x81\x8a\xe3\x81\x8b\xe3\x81\x8d\xe3\x81\x8f\xe3\x81\x91 (esc)
\xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88\xe3\x81\x8a\xe3\x81\x8b\xe3\x81\x8d\xe3\x81\x8f\xe3\x81\x91\xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88\xe3\x81\x8a\xe3\x81\x8b\xe3\x81\x8d\xe3\x81\x8f\xe3\x81\x91\xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88\xe3\x81\x8a\xe3\x81\x8b\xe3\x81\x8d\xe3\x81\x8f\xe3\x81\x91 (esc)
\xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88\xe3\x81\x8a\xe3\x81\x8b\xe3\x81\x8d\xe3\x81\x8f\xe3\x81\x91 (esc)
(some details hidden, use --verbose to show complete help)
(1-3) display Japanese half-width characters in cp932
$ COLUMNS=60 hg --encoding cp932 --config extensions.show=./show.py help show_half_ja
hg show_half_ja
\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9 \xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9 \xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9 \xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9 (esc)
\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9 \xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9 \xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9 \xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9 \xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9 (esc)
\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9 \xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9 \xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9 (esc)
\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9 (esc)
\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9 (esc)
(some details hidden, use --verbose to show complete help)
(1-4) display Japanese half-width characters in utf-8
$ COLUMNS=60 hg --encoding utf-8 --config extensions.show=./show.py help show_half_ja
hg show_half_ja
\xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9 \xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9 \xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9 \xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9 (esc)
\xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9 \xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9 \xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9 \xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9 \xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9 (esc)
\xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9 \xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9 \xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9 (esc)
\xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9\xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9\xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9\xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9\xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9\xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9 (esc)
\xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9\xef\xbd\xb1\xef\xbd\xb2\xef\xbd\xb3\xef\xbd\xb4\xef\xbd\xb5\xef\xbd\xb6\xef\xbd\xb7\xef\xbd\xb8\xef\xbd\xb9 (esc)
(some details hidden, use --verbose to show complete help)
(2) test text wrapping for ambiguous-width characters
(2-1) treat width of ambiguous characters as narrow (default)
(2-1-1) display Japanese ambiguous-width characters in cp932
$ COLUMNS=60 hg --encoding cp932 --config extensions.show=./show.py help show_ambig_ja
hg show_ambig_ja
\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b \x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b \x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b (esc)
\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b \x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b \x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b \x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b \x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b (esc)
\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b \x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b (esc)
\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b (esc)
\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b (esc)
(some details hidden, use --verbose to show complete help)
(2-1-2) display Japanese ambiguous-width characters in utf-8
$ COLUMNS=60 hg --encoding utf-8 --config extensions.show=./show.py help show_ambig_ja
hg show_ambig_ja
\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b \xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b \xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b (esc)
\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b \xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b \xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b \xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b \xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b (esc)
\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b \xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b (esc)
\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b (esc)
\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b (esc)
(some details hidden, use --verbose to show complete help)
(2-1-3) display Russian ambiguous-width characters in cp1251
$ COLUMNS=60 hg --encoding cp1251 --config extensions.show=./show.py help show_ambig_ru
hg show_ambig_ru
\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 \xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 \xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 \xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 \xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 (esc)
\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 \xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 \xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 \xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 \xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 (esc)
\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 (esc)
\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 (esc)
\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 (esc)
(some details hidden, use --verbose to show complete help)
(2-1-4) display Russian ambiguous-width characters in utf-8
$ COLUMNS=60 hg --encoding utf-8 --config extensions.show=./show.py help show_ambig_ru
hg show_ambig_ru
\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 \xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 \xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 \xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 \xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 (esc)
\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 \xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 \xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 \xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 \xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 (esc)
\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 (esc)
\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 (esc)
\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 (esc)
(some details hidden, use --verbose to show complete help)
(2-2) treat width of ambiguous characters as wide
(2-2-1) display Japanese ambiguous-width characters in cp932
$ COLUMNS=60 HGENCODINGAMBIGUOUS=wide hg --encoding cp932 --config extensions.show=./show.py help show_ambig_ja
hg show_ambig_ja
\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b \x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b \x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b (esc)
\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b \x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b (esc)
\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b \x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b (esc)
\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b \x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b (esc)
\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b (esc)
\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b (esc)
\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b (esc)
\x83\xbf\x83\xc0\x83\xc1\x83\xc2\x83\xd2\x83\xc4\x83\xc5\x83\xc6\x81\x9b (esc)
(some details hidden, use --verbose to show complete help)
(2-2-2) display Japanese ambiguous-width characters in utf-8
$ COLUMNS=60 HGENCODINGAMBIGUOUS=wide hg --encoding utf-8 --config extensions.show=./show.py help show_ambig_ja
hg show_ambig_ja
\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b \xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b \xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b (esc)
\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b \xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b (esc)
\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b \xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b (esc)
\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b \xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b (esc)
\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b (esc)
\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b (esc)
\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b (esc)
\xce\xb1\xce\xb2\xce\xb3\xce\xb4\xcf\x85\xce\xb6\xce\xb7\xce\xb8\xe2\x97\x8b (esc)
(some details hidden, use --verbose to show complete help)
(2-2-3) display Russian ambiguous-width characters in cp1251
$ COLUMNS=60 HGENCODINGAMBIGUOUS=wide hg --encoding cp1251 --config extensions.show=./show.py help show_ambig_ru
hg show_ambig_ru
\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 \xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 \xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 (esc)
\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 \xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 (esc)
\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 \xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 (esc)
\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 \xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 (esc)
\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 \xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 (esc)
\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 (esc)
\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 (esc)
\xcd\xe0\xf1\xf2\xf0\xee\xe9\xea\xe8 (esc)
(some details hidden, use --verbose to show complete help)
(2-2-4) display Russian ambiguous-width characters in utf-8
$ COLUMNS=60 HGENCODINGAMBIGUOUS=wide hg --encoding utf-8 --config extensions.show=./show.py help show_ambig_ru
hg show_ambig_ru
\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 \xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 \xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 (esc)
\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 \xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 (esc)
\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 \xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 (esc)
\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 \xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 (esc)
\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 \xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 (esc)
\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 (esc)
\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 (esc)
\xd0\x9d\xd0\xb0\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xb9\xd0\xba\xd0\xb8 (esc)
(some details hidden, use --verbose to show complete help)
$ cd ..