Re: [PATCHv2] Add optional styled argument to gdb.execute

[Marco Barisione <mbarisione@undo.io>]

On 20 May 2021, at 17:34, Hannes Domani via Gdb-patches <gdb-patches@sourceware.org> wrote:
> Am Donnerstag, 20. Mai 2021, 18:12:47 MESZ hat Simon Marchi <simon.marchi@polymtl.ca> Folgendes geschrieben:
> 
>> On 2021-05-20 11:42 a.m., Hannes Domani wrote:
>>> When I call gdb.execute() with to_string=False, the output to stdout is colored,
>>> so do you mean styled=False should disable the colors?
>> 
>> Yes.  Well, I'm asking whether we might want that in the future (to be
>> able to control styling when using gdb.execute with to_string=False).
>> If we might want that in the future, I think it would be natural to use
>> the "styled" parameter for this.  And so I ask whether a simple
>> True/False boolean will be enough for this, given that True/False would
>> (presumably) force the styling to on or off.  Will there be a need for a
>> third (default) value to say "do whatever the default is"?
> 
> I'm not sure it's necessary, anyone who wants styling enabled/disabled,
> can call gdb.execute(to_string=True) with styled True/False, and just print
> the output string.

This is not the same as the command may take time, so you don’t want to
delay the printing until the command is finished.


In the project I work on, I use an older version of this patch (which,
by the way, works great).  My use case is to get the output of the
command, do some stuff to it and print it back.

Simon,  I’m not sure I understand correctly your proposal about
using None/True/False.  Do you mean that when styled=True the output
would be styled even if you did "set style enabled off"?
I think this would make writing code more complicated as there would
be no easy way to achieve what I think is the patch’s original purpose,
i.e. just get a string containing what GDB would have printed to the
terminal.

On the other hand, disabling styling temporarily is trivial.  I use
code similar to this in the project I work on:

    @contextlib.contextmanager
    def style_disabled():
        enabled_before = gdb.parameter("style enabled")

        try:
            gdb.execute("set style enabled off")
            yield
        finally:
            if enabled_before:
                gdb.execute("set style enabled on")


    with style_disabled():
        gdb.execute("backtrace")


-- 
Marco Barisione