Git 2.28 Release Notes
======================

Updates since v2.27
-------------------

Backward compatibility notes

 * "feature.experimental" configuration variable is to let volunteers
   easily opt into a set of newer features, which use of the v2
   transport protocol is now a part of.


UI, Workflows & Features

 * The commands in the "diff" family learned to honor "diff.relative"
   configuration variable.

 * The check in "git fsck" to ensure that the tree objects are sorted
   still had corner cases it missed unsorted entries.

 * The interface to redact sensitive information in the trace output
   has been simplified.

 * The command line completion (in contrib/) learned to complete
   options that the "git switch" command takes.

 * "git diff" used to take arguments in random and nonsense range
   notation, e.g. "git diff A..B C", "git diff A..B C...D", etc.,
   which has been cleaned up.


Performance, Internal Implementation, Development Support etc.

 * Code optimization for a common case.
   (merge 8777616e4d an/merge-single-strategy-optim later to maint).

 * We've adopted a convention that any on-stack structure can be
   initialized to have zero values in all fields with "= { 0 }",
   even when the first field happens to be a pointer, but sparse
   complained that a null pointer should be spelled NULL for a long
   time.  Start using -Wno-universal-initializer option to squelch
   it (the latest sparse has it on by default).

 * "git log -L..." now takes advantage of the "which paths are touched
   by this commit?" info stored in the commit-graph system.

 * As FreeBSD is not the only platform whose regexp library reports
   a REG_ILLSEQ error when fed invalid UTF-8, add logic to detect that
   automatically and skip the affected tests.

 * "git bugreport" learns to report what shell is in use.

 * Support for GIT_CURL_VERBOSE has been rewritten in terms of
   GIT_TRACE_CURL.

 * Preliminary clean-ups around refs API, plus file format
   specification documentation for the reftable backend.

 * Workaround breakage in MSVC build, where "curl-config --cflags"
   gives settings appropriate for GCC build.

 * Code clean-up of "git clean" resulted in a fix of recent
   performance regression.

 * Code clean-up in the codepath that serves "git fetch" continues.

 * "git merge-base --is-ancestor" is taught to take advantage of the
   commit graph.

 * Rewrite of parts of the scripted "git submodule" Porcelain command
   continues; this time it is "git submodule set-branch" subcommand's
   turn.

 * The "fetch/clone" protocol has been updated to allow the server to
   instruct the clients to grab pre-packaged packfile(s) in addition
   to the packed object data coming over the wire.


Fixes since v2.27
-----------------

 * The "--prepare-p4-only" option of "git p4" is supposed to stop
   after replaying one changeset, but kept going (by mistake?)

 * The error message from "git checkout -b foo -t bar baz" was
   confusing.

 * Some repositories in the wild have commits that record nonsense
   committer timezone (e.g. rails.git); "git fast-import" learned an
   option to pass these nonsense timestamps intact to allow recreating
   existing repositories as-is.
   (merge d42a2fb72f en/fast-import-looser-date later to maint).

 * The command line completion script (in contrib/) tried to complete
   "git stash -p" as if it were "git stash push -p", but it was too
   aggressive and also affected "git stash show -p", which has been
   corrected.
   (merge fffd0cf520 vs/complete-stash-show-p-fix later to maint).

 * On-the-wire protocol v2 easily falls into a deadlock between the
   remote-curl helper and the fetch-pack process when the server side
   prematurely throws an error and disconnects.  The communication has
   been updated to make it more robust.

 * "git checkout -p" did not handle a newly added path at all.
   (merge 2c8bd8471a js/checkout-p-new-file later to maint).

 * The code to parse "git bisect start" command line was lax in
   validating the arguments.
   (merge 4d9005ff5d cb/bisect-helper-parser-fix later to maint).

 * Reduce memory usage during "diff --quiet" in a worktree with too
   many stat-unmatched paths.
   (merge d2d7fbe129 jk/diff-memuse-optim-with-stat-unmatch later to maint).

 * The reflog entries for "git clone" and "git fetch" did not
   anonymize the URL they operated on.
   (merge 46da295a77 js/reflog-anonymize-for-clone-and-fetch later to maint).

 * The behaviour of "sparse-checkout" in the state "git clone
   --no-checkout" left was changed accidentally in 2.27, which has
   been corrected.

 * Use of negative pathspec, while collecting paths including
   untracked ones in the working tree, was broken.

 * The same worktree directory must be registered only once, but
   "git worktree move" allowed this invariant to be violated, which
   has been corrected.
   (merge 810382ed37 es/worktree-duplicate-paths later to maint).

 * The effect of sparse checkout settings on submodules is documented.
   (merge e7d7c73249 en/sparse-with-submodule-doc later to maint).

 * Code clean-up around "git branch" with a minor bugfix.
   (merge dc44639904 dl/branch-cleanup later to maint).

 * A branch name used in a test has been clarified to match what is
   going on.
   (merge 08dc26061f pb/t4014-unslave later to maint).

 * Other code cleanup, docfix, build fix, etc.
   (merge 2c31a7aa44 jx/pkt-line-doc-count-fix later to maint).
   (merge d63ae31962 cb/t5608-cleanup later to maint).
   (merge 788db145c7 dl/t-readme-spell-git-correctly later to maint).
   (merge 45a87a83bb dl/python-2.7-is-the-floor-version later to maint).
   (merge b75a219904 es/advertise-contribution-doc later to maint).