I have tested this patch with a repo that contains quite a few binary files
(and patches), using 'time darcs check' on that repo. With this patch the
runtime consistently drops from about 16 seconds to about 12.5 seconds, a
25% improvement for very little effort. I propose to include this in
darcs-2.16.3.

1 patch for repository http://darcs.net/screened:

patch 2f3c6267502d79c4762230b4282088d10c7386f7
Author: Ben Franksen <ben.franksen@online.de>
Date:   Fri Sep 18 11:03:00 CEST 2020
  * drop dependency on sandi and use base16-bytestring >= 1.0
  
  This was prompted by the announcement of base16-bytestring-1.0.0.0 which
  claims to give major performance improvements and a simpler API. As we use
  sandi only for base16 en/decoding and already depended on base16-bytestring
  in addition to that, this seemed like a logical step. It also turned out
  that the API of base16-bytestring fits our conventions better, in particular
  we can drop the separate pass that converts between upper and lower case,
  which should give us further performance improvement.

Attachments

• drop-dependency-on-sandi-and-use-base16_bytestring-__-1_0.dpatch
• patch-preview.txt
• unnamed

Looks good.