Re: [PATCH] mergetools/meld: improve backwards-compatibiilty when using "--output"

[Samuel Lijin <sxlijin@gmail.com>]

On Sun, Jun 18, 2017 at 8:17 PM, David Aguilar <davvid@gmail.com> wrote:
> On Sun, Jun 18, 2017 at 05:11:48AM -0400, Samuel Lijin wrote:
>> On Sun, Jun 18, 2017 at 3:46 AM, David Aguilar <davvid@gmail.com> wrote:
>> > On Sat, Jun 17, 2017 at 10:11:36AM -0400, Samuel Lijin wrote:
>> >> On Sat, Jun 17, 2017 at 6:24 AM, David Aguilar <davvid@gmail.com> wrote:
>> >> > Meld 3.16.0 requires a "=" in the --output argument, as it uses
>> >> > a simple hand-rolled command-line parser.
>> >> >
>> >> > Newer versions of Meld (3.16.4, and possibly earlier) use
>> >> > optpaarse, which accepts either "--output <file>" or
>> >> > "--output=<file>".
>> >
>> > Junio, there's an optpaarse -> optparse typo in the commit message
>> > here in case you want to fix that up.
>> >
>> >>
>> >> Do older versions also support both?
>> >
>> > No.  When the "--output" option was first added (3.16.0, or possibly
>> > earlier) it used the simpler parser that does not undertand the
>> > "--output <filename>" form.
>> >
>> > Much older versions didn't support "--output" at all, so we don't have
>> > to worry about them since we already use the "--output" flag
>> > selectively based on whether or not it's supported.
>>
>> It sounds like this patch would break versions of Meld that use the
>> hand-rolled parser, then.
>
> I don't think so.
>
> The whole point of this patch is to make it compatible with the
> hand-rolled parser.
>
> Before the patch:
>
>         --output <filename>
>
> After the patch:
>
>         --output=<filename>
>
>
> The form with "=" (the latter one) is the one that's maximally
> compatible.
>
> Please re-read the commit message and patch to verify that this is
> indeed true.

Whoops, sorry, yes, you're right. It does still sound like there are
some versions of Meld in the middle that rely on "--output <filename>"
though, that this does break.