Mercurial 4.0 release

Features

• The following commands now also have experimental formatter support: 'hg version', 'hg grep' and 'hg config'

• New template keywords and functions: termwidth, mod(a, b), relpath(path)

• Basic arithmetic operations in template such as termwidth - 10

• follow() revset takes new startrev parameter

• Bash completion now allows skipping potentially expensive status call for completing 'hg status' arguments, using $HGCOMPLETE_NOSTATUS environment variable

Improvements

• A number of changes were made to move and copy tracking, to make sure move and copy information is not lost during commands like 'hg graft'
• Compound revset expression is now properly ordered
• Performance of client-side application of bundle data for generaldelta repos has been significantly improved. This makes 'hg clone', 'hg pull', and 'hg unbundle' operations faster. Cloning the Firefox repository now consumes 70+s less CPU time and completes over a minute faster (when not network or I/O bound).
• The storage and transfer of changeset data has been optimized to improve read performance
• Python 3 support has received a lot of improvements (but will take a lot of additional work)
• zlib performance in hgweb is improved, and it's now possible to control zlib compression level using server.zliblevel option
• Various improvements for largefiles extension related to executable bit tracking and removing files, better recovery from an interrupted state

A full overview is available on WhatsNew.