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

On Sun, Jun 18, 2017 at 05:11:48AM -0400, Samuel Lijin wrote:

On Sun, Jun 18, 2017 at 3:46 AM, David Aguilar [off-list ref] wrote:

quoted

On Sat, Jun 17, 2017 at 10:11:36AM -0400, Samuel Lijin wrote:

quoted

On Sat, Jun 17, 2017 at 6:24 AM, David Aguilar [off-list ref] wrote:

quoted

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.

quoted

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.
-- 
David