Re: [GSOC PATCH 1/2] environment: remove the global variable 'merge_log_config'

>
> Ayush Chandekar <ayu.chandekar@gmail.com> writes:
>
> > The global variable 'merge_log_config', set via the "merge.log" or
> > "merge.summary" settings, is only used in 'cmd_fmt_merge_msg()' and
> > 'cmd_merge()' to adjust the 'shortlog_len' variable.
> >
> > Remove 'merge_log_config' and introduce a function
> > 'adjust_shortlog_len()' in fmt-merge-msg.c to handle the 'shortlog_len'
> > variable.
> >
> > This change is part of an ongoing effort to eliminate global variables,
> > improve modularity and help libify the codebase.
>
> And the downsides of this change are...?
>
> One obvious behaviour change I can see can happen when you have an
> invalid value set to merge.summary and run the command with command
> line override with the "--log" option.  In the current code, the
> config callback barfs when it notices an invalid merge.summary
> setting, even though it won't be used because the valid value given
> via the "--log" option would override it.  In the updated code,
> adjust_shortlog_len() would short-circuit and does not even bother
> reading from the configuration, so the user will not be notified of
> a broken configuration.
>
> It is not immediately obvious if this particular behaviour change is
> a regression or an improvement, but it probably deserves to be noted
> somewhere to help future developers what our thinking was.