Subject: 28.0.50; Incompatible change to sql-add-product in Emacs 27

From: Philipp <[email-masked]>
Date: Fri, 06 Mar 2020 23:39:16 +0100

In Emacs 26, sql-add-product has the signature

(sql-add-product PRODUCT DISPLAY &rest PLIST)

However, in the Emacs 27 pretest the signature is now

(sql-add-product PRODUCT DISPLAY &optional PLIST)

Note the change from &rest to &optional.  This is a breaking change that
breaks all users of sql-add-product.  I've found quite a few uses of the
old signature in the wild,
e.g. https://github.com/kat-co/sql-prestodb/blob/f4a74d88dcb166445bb41efb865147c0faf1de3a/src/sql-presto.el#L59
or
https://github.com/r0man/vertica-el/blob/3c9647b425c5c13c30bf0cba483646af18196588/vertica.el#L68
or
https://github.com/jterk/sql-impala/blob/466e7c0c789ec3e5e8a276c8f6754f91bb584c3e/sql-impala.el#L71.
This change was introduced in commit
c124d5323c05a4010db9b2d330575d029936ade1.  I don't think we should
introduce such a breaking change to a widely-used public function; at
the very least, Emacs 27 should accept both signatures.

In GNU Emacs 28.0.50 (build 39, x86_64-apple-darwin19.3.0, NS appkit-1894.30 Version 10.15.3 (Build 19D76))
 of 2020-02-29
Repository revision: 3d2c82ac96a7f37e60b2b85a5c9c1d792084ab54
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