[Bug 58665] New: cmd incorrectly wraps text containing ANSI escape sequences

[WineHQ Bugzilla]

http://bugs.winehq.org/show_bug.cgi?id=58665

Bug ID: 58665
           Summary: cmd incorrectly wraps text containing ANSI escape
                    sequences
           Product: Wine
           Version: 10.14
          Hardware: x86-64
                OS: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: cmd
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

Created attachment 79250
  --> http://bugs.winehq.org/attachment.cgi?id=79250
reproducer: should print 3 lines; wine prints 4 lines

Wine's cmd.exe prematurely inserts line breaks when a program's output contains
non-printable ANSI escape sequences, such as those used to change colors.

It looks as though Wine is counting not only the printable characters in the
program's output, but also the non-printable ones, and using the total to
decide where to insert a line break. Text that fits entirely on one line in a
real Windows console is sometimes broken midway through the line, or followed
by a blank line that should not be there, when run in an xterm using Wine.

I am attaching a batch file that reproduces the problem. It should print 3
lines. The second line is identical to the others with the addition of some
non-printable escape sequences. These characters should either occupy no width
in the terminal (making the line length match the others) or be rendered as
visible placeholder characters (as older Windows versions do). To see Wine
handling it incorrectly, run it in an 80-column xterm or a similar terminal.

Ideally, the output should look like this, with the head of line 2 in red:

79 chars _123456789_123456789_123456789_123456789_123456789_123456789_123456789
79 chars _123456789_123456789_123456789_123456789_123456789_123456789_123456789
79 chars _123456789_123456789_123456789_123456789_123456789_123456789_123456789

In wine, the output looks like this:

79 chars _123456789_123456789_123456789_123456789_123456789_123456789_123456789
79 chars _123456789_123456789_123456789_123456789_123456789_123456789_12
3456789
79 chars _123456789_123456789_123456789_123456789_123456789_123456789_123456789

Bug 49780 is related, but IMHO does not excuse this behavior. Regardless of
whether virtual terminal sequences are supported, Wine should either print a
character or not count it toward the length of a line when deciding where to
wrap it.

[Bug 58665] cmd incorrectly wraps text containing ANSI escape sequences

[WineHQ Bugzilla]

http://bugs.winehq.org/show_bug.cgi?id=58665

Eric Pouech  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |[e-mail]

--- Comment #1 from Eric Pouech  ---
there are several issues involved:

1) cmd.exe was erroneously breaking lines. funnily enough, this has been fixed
yesterday (see [1])

2) as already stated in bug 49780, conhost doesn't support yet ansi esc
sequence (bug 49780), nor does it recognize them
so it treats them as regular output, hence taking them into account when
wrapping lines

Note: this is the expected behavior when virtual terminal processing is not
activated for the console (native does this as well)

2a) when using a unix console (eg. running ./wine cmd from unix prompt)
output is sent to underlying unix terminal, which will handle the esc sequences
(note: this will only work if the windows esc sequences matches the selected
one in unix terminal; will likely work for color, bold, italic, but might break
for more exotic ones)
retested with [1] applied, and 79 is printed in red on second line as expected
(yet wrapped as explained in 2)

2b) when using a windowed console (eg. running ./wine wineconsole cmd)
same wrapping issue. however, the escape sequences are printed

in short:
- I can't repro the state you're reporting (esp sequence not printed but line
wrapped). can you retest with [1] applied, and if the behavior you see doesn't
match what's described above, please detail which console you're using (and if
in 2a, which terminal emulator and which term settings)
- we don't have anything in place for silencing the esc seq on output, and
likely won't add it.
- the only reasonable solution is to fix 49780

[1]
https://gitlab.winehq.org/wine/wine/-/commit/adad7016757de9a53dab2dc688d14bb...)