RelNotes/2.32.0.adoc

Git 2.32 Release Notes
======================

Backward compatibility notes
----------------------------

 * ".gitattributes", ".gitignore", and ".mailmap" files that are
   symbolic links are ignored.

 * "git apply --3way" used to first attempt a straight application,
   and only fell back to the 3-way merge algorithm when the stright
   application failed.  Starting with this version, the command will
   first try the 3-way merge algorithm and only when it fails (either
   resulting with conflict or the base versions of blobs are missing),
   falls back to the usual patch application.


Updates since v2.31
-------------------

UI, Workflows & Features

 * It does not make sense to make ".gitattributes", ".gitignore" and
   ".mailmap" symlinks, as they are supposed to be usable from the
   object store (think: bare repositories where HEAD:.mailmap etc. are
   used).  When these files are symbolic links, we used to read the
   contents of the files pointed by them by mistake, which has been
   corrected.

 * "git stash show" learned to optionally show untracked part of the
   stash.

 * "git log --format='...'" learned "%(describe)" placeholder.

 * "git repack" so far has been only capable of repacking everything
   under the sun into a single pack (or split by size).  A cleverer
   strategy to reduce the cost of repacking a repository has been
   introduced.

 * The http codepath learned to let the credential layer to cache the
   password used to unlock a certificate that has successfully been
   used.

 * "git commit --fixup=<commit>", which was to tweak the changes made
   to the contents while keeping the original log message intact,
   learned "--fixup=(amend|reword):<commit>", that can be used to
   tweak both the message and the contents, and only the message,
   respectively.

 * "git send-email" learned to honor the core.hooksPath configuration.

 * "git format-patch -v<n>" learned to allow a reroll count that is
   not an integer.

 * "git commit" learned "--trailer <key>[=<value>]" option; together
   with the interpret-trailers command, this will make it easier to
   support custom trailers.

 * "git clone --reject-shallow" option fails the clone as soon as we
   notice that we are cloning from a shallow repository.

 * A configuration variable has been added to force tips of certain
   refs to be given a reachability bitmap.

 * "gitweb" learned "e-mail privacy" feature to redact strings that
   look like e-mail addresses on various pages.

 * "git apply --3way" has always been "to fall back to 3-way merge
   only when straight application fails". Swap the order of falling
   back so that 3-way is always attempted first (only when the option
   is given, of course) and then straight patch application is used as
   a fallback when it fails.

 * "git apply" now takes "--3way" and "--cached" at the same time, and
   work and record results only in the index.

 * The command line completion (in contrib/) has learned that
   CHERRY_PICK_HEAD is a possible pseudo-ref.

 * Userdiff patterns for "Scheme" has been added.

 * "git log" learned "--diff-merges=<style>" option, with an
   associated configuration variable log.diffMerges.

 * "git log --format=..." placeholders learned %ah/%ch placeholders to
   request the --date=human output.

 * Replace GIT_CONFIG_NOSYSTEM mechanism to decline from reading the
   system-wide configuration file with GIT_CONFIG_SYSTEM that lets
   users specify from which file to read the system-wide configuration
   (setting it to an empty file would essentially be the same as
   setting NOSYSTEM), and introduce GIT_CONFIG_GLOBAL to override the
   per-user configuration in $HOME/.gitconfig.

 * "git add" and "git rm" learned not to touch those paths that are
   outside of sparse checkout.

 * "git rev-list" learns the "--filter=object:type=<type>" option,
   which can be used to exclude objects of the given kind from the
   packfile generated by pack-objects.

 * The command line completion (in contrib/) for "git stash" has been
   updated.

 * "git subtree" updates.

 * It is now documented that "format-patch" skips merges.

 * Options to "git pack-objects" that take numeric values like
   --window and --depth should not accept negative values; the input
   validation has been tightened.

 * The way the command line specified by the trailer.<token>.command
   configuration variable receives the end-user supplied value was
   both error prone and misleading.  An alternative to achieve the
   same goal in a safer and more intuitive way has been added, as
   the trailer.<token>.cmd configuration variable, to replace it.

 * "git add -i --dry-run" does not dry-run, which was surprising.  The
   combination of options has taught to error out.

 * "git push" learns to discover common ancestor with the receiving
   end over protocol v2.  This will hopefully make "git push" as
   efficient as "git fetch" in avoiding objects from getting
   transferred unnecessarily.

 * "git mailinfo" (hence "git am") learned the "--quoted-cr" option to
   control how lines ending with CRLF wrapped in base64 or qp are
   handled.


Performance, Internal Implementation, Development Support etc.

 * Rename detection rework continues.

 * GIT_TEST_FAIL_PREREQS is a mechanism to skip test pieces with
   prerequisites to catch broken tests that depend on the side effects
   of optional pieces, but did not work at all when negative
   prerequisites were involved.
   (merge 27d578d904 jk/fail-prereq-testfix later to maint).

 * "git diff-index" codepath has been taught to trust fsmonitor status
   to reduce number of lstat() calls.
   (merge 7e5aa13d2c nk/diff-index-fsmonitor later to maint).

 * Reorganize Makefile to allow building git.o and other essential
   objects without extra stuff needed only for testing.

 * Preparatory API changes for parallel checkout.

 * A simple IPC interface gets introduced to build services like
   fsmonitor on top.

 * Fsck API clean-up.

 * SECURITY.md that is facing individual contributors and end users
   has been introduced.  Also a procedure to follow when preparing
   embargoed releases has been spelled out.
   (merge 09420b7648 js/security-md later to maint).

 * Optimize "rev-list --use-bitmap-index --objects" corner case that
   uses negative tags as the stopping points.

 * CMake update for vsbuild.

 * An on-disk reverse-index to map the in-pack location of an object
   back to its object name across multiple packfiles is introduced.

 * Generate [ec]tags under $(QUIET_GEN).

 * Clean-up codepaths that implements "git send-email --validate"
   option and improves the message from it.

 * The last remnant of gettext-poison has been removed.

 * The test framework has been taught to optionally turn the default
   merge strategy to "ort" throughout the system where we use
   three-way merges internally, like cherry-pick, rebase etc.,
   primarily to enhance its test coverage (the strategy has been
   available as an explicit "-s ort" choice).

 * A bit of code clean-up and a lot of test clean-up around userdiff
   area.

 * Handling of "promisor packs" that allows certain objects to be
   missing and lazily retrievable has been optimized (a bit).

 * When packet_write() fails, we gave an extra error message
   unnecessarily, which has been corrected.

 * The checkout machinery has been taught to perform the actual
   write-out of the files in parallel when able.

 * Show errno in the trace output in the error codepath that calls
   read_raw_ref method.

 * Effort to make the command line completion (in contrib/) safe with
   "set -u" continues.

 * Tweak a few tests for "log --format=..." that show timestamps in
   various formats.

 * The reflog expiry machinery has been taught to emit trace events.

 * Over-the-wire protocol learns a new request type to ask for object
   sizes given a list of object names.


Fixes since v2.31
-----------------

 * The fsmonitor interface read from its input without making sure
   there is something to read from.  This bug is new in 2.31
   timeframe.

 * The data structure used by fsmonitor interface was not properly
   duplicated during an in-core merge, leading to use-after-free etc.

 * "git bisect" reimplemented more in C during 2.30 timeframe did not
   take an annotated tag as a good/bad endpoint well.  This regression
   has been corrected.

 * Fix macros that can silently inject unintended null-statements.

 * CALLOC_ARRAY() macro replaces many uses of xcalloc().

 * Update insn in Makefile comments to run fuzz-all target.

 * Fix a corner case bug in "git mv" on case insensitive systems,
   which was introduced in 2.29 timeframe.

 * We had a code to diagnose and die cleanly when a required
   clean/smudge filter is missing, but an assert before that
   unnecessarily fired, hiding the end-user facing die() message.
   (merge 6fab35f748 mt/cleanly-die-upon-missing-required-filter later to maint).

 * Update C code that sets a few configuration variables when a remote
   is configured so that it spells configuration variable names in the
   canonical camelCase.
   (merge 0f1da600e6 ab/remote-write-config-in-camel-case later to maint).

 * A new configuration variable has been introduced to allow choosing
   which version of the generation number gets used in the
   commit-graph file.
   (merge 702110aac6 ds/commit-graph-generation-config later to maint).

 * Perf test update to work better in secondary worktrees.
   (merge 36e834abc1 jk/perf-in-worktrees later to maint).

 * Updates to memory allocation code around the use of pcre2 library.
   (merge c1760352e0 ab/grep-pcre2-allocfix later to maint).

 * "git -c core.bare=false clone --bare ..." would have segfaulted,
   which has been corrected.
   (merge 75555676ad bc/clone-bare-with-conflicting-config later to maint).

 * When "git checkout" removes a path that does not exist in the
   commit it is checking out, it wasn't careful enough not to follow
   symbolic links, which has been corrected.
   (merge fab78a0c3d mt/checkout-remove-nofollow later to maint).

 * A few option description strings started with capital letters,
   which were corrected.
   (merge 5ee90326dc cc/downcase-opt-help later to maint).

 * Plug or annotate remaining leaks that trigger while running the
   very basic set of tests.
   (merge 68ffe095a2 ah/plugleaks later to maint).

 * The hashwrite() API uses a buffering mechanism to avoid calling
   write(2) too frequently. This logic has been refactored to be
   easier to understand.
   (merge ddaf1f62e3 ds/clarify-hashwrite later to maint).

 * "git cherry-pick/revert" with or without "--[no-]edit" did not spawn
   the editor as expected (e.g. "revert --no-edit" after a conflict
   still asked to edit the message), which has been corrected.
   (merge 39edfd5cbc en/sequencer-edit-upon-conflict-fix later to maint).

 * "git daemon" has been tightened against systems that take backslash
   as directory separator.
   (merge 9a7f1ce8b7 rs/daemon-sanitize-dir-sep later to maint).

 * A NULL-dereference bug has been corrected in an error codepath in
   "git for-each-ref", "git branch --list" etc.
   (merge c685450880 jk/ref-filter-segfault-fix later to maint).

 * Streamline the codepath to fix the UTF-8 encoding issues in the
   argv[] and the prefix on macOS.
   (merge c7d0e61016 tb/precompose-prefix-simplify later to maint).

 * The command-line completion script (in contrib/) had a couple of
   references that would have given a warning under the "-u" (nounset)
   option.
   (merge c5c0548d79 vs/completion-with-set-u later to maint).

 * When "git pack-objects" makes a literal copy of a part of existing
   packfile using the reachability bitmaps, its update to the progress
   meter was broken.
   (merge 8e118e8490 jk/pack-objects-bitmap-progress-fix later to maint).

 * The dependencies for config-list.h and command-list.h were broken
   when the former was split out of the latter, which has been
   corrected.
   (merge 56550ea718 sg/bugreport-fixes later to maint).

 * "git push --quiet --set-upstream" was not quiet when setting the
   upstream branch configuration, which has been corrected.
   (merge f3cce896a8 ow/push-quiet-set-upstream later to maint).

 * The prefetch task in "git maintenance" assumed that "git fetch"
   from any remote would fetch all its local branches, which would
   fetch too much if the user is interested in only a subset of
   branches there.
   (merge 32f67888d8 ds/maintenance-prefetch-fix later to maint).

 * Clarify that pathnames recorded in Git trees are most often (but
   not necessarily) encoded in UTF-8.
   (merge 9364bf465d ab/pathname-encoding-doc later to maint).

 * "git --config-env var=val cmd" weren't accepted (only
   --config-env=var=val was).
   (merge c331551ccf ps/config-env-option-with-separate-value later to maint).

 * When the reachability bitmap is in effect, the "do not lose
   recently created objects and those that are reachable from them"
   safety to protect us from races were disabled by mistake, which has
   been corrected.
   (merge 2ba582ba4c jk/prune-with-bitmap-fix later to maint).

 * Cygwin pathname handling fix.
   (merge bccc37fdc7 ad/cygwin-no-backslashes-in-paths later to maint).

 * "git rebase --[no-]reschedule-failed-exec" did not work well with
   its configuration variable, which has been corrected.
   (merge e5b32bffd1 ab/rebase-no-reschedule-failed-exec later to maint).

 * Portability fix for command line completion script (in contrib/).
   (merge f2acf763e2 si/zsh-complete-comment-fix later to maint).

 * "git repack -A -d" in a partial clone unnecessarily loosened
   objects in promisor pack.

 * "git bisect skip" when custom words are used for new/old did not
   work, which has been corrected.

 * A few variants of informational message "Already up-to-date" has
   been rephrased.
   (merge ad9322da03 js/merge-already-up-to-date-message-reword later to maint).

 * "git submodule update --quiet" did not propagate the quiet option
   down to underlying "git fetch", which has been corrected.
   (merge 62af4bdd42 nc/submodule-update-quiet later to maint).

 * Document that our test can use "local" keyword.
   (merge a84fd3bcc6 jc/test-allows-local later to maint).

 * The word-diff mode has been taught to work better with a word
   regexp that can match an empty string.
   (merge 0324e8fc6b pw/word-diff-zero-width-matches later to maint).

 * "git p4" learned to find branch points more efficiently.
   (merge 6b79818bfb jk/p4-locate-branch-point-optim later to maint).

 * When "git update-ref -d" removes a ref that is packed, it left
   empty directories under $GIT_DIR/refs/ for
   (merge 5f03e5126d wc/packed-ref-removal-cleanup later to maint).

 * "git clean" and "git ls-files -i" had confusion around working on
   or showing ignored paths inside an ignored directory, which has
   been corrected.
   (merge b548f0f156 en/dir-traversal later to maint).

 * The handling of "%(push)" formatting element of "for-each-ref" and
   friends was broken when the same codepath started handling
   "%(push:<what>)", which has been corrected.
   (merge 1e1c4c5eac zh/ref-filter-push-remote-fix later to maint).

 * The bash prompt script (in contrib/) did not work under "set -u".
   (merge 5c0cbdb107 en/prompt-under-set-u later to maint).

 * The "chainlint" feature in the test framework is a handy way to
   catch common mistakes in writing new tests, but tends to get
   expensive.  An knob to selectively disable it has been introduced
   to help running tests that the developer has not modified.
   (merge 2d86a96220 jk/test-chainlint-softer later to maint).

 * The "rev-parse" command did not diagnose the lack of argument to
   "--path-format" option, which was introduced in v2.31 era, which
   has been corrected.
   (merge 99fc555188 wm/rev-parse-path-format-wo-arg later to maint).

 * Other code cleanup, docfix, build fix, etc.
   (merge f451960708 dl/cat-file-doc-cleanup later to maint).
   (merge 12604a8d0c sv/t9801-test-path-is-file-cleanup later to maint).
   (merge ea7e63921c jr/doc-ignore-typofix later to maint).
   (merge 23c781f173 ps/update-ref-trans-hook-doc later to maint).
   (merge 42efa1231a jk/filter-branch-sha256 later to maint).
   (merge 4c8e3dca6e tb/push-simple-uses-branch-merge-config later to maint).
   (merge 6534d436a2 bs/asciidoctor-installation-hints later to maint).
   (merge 47957485b3 ab/read-tree later to maint).
   (merge 2be927f3d1 ab/diff-no-index-tests later to maint).
   (merge 76593c09bb ab/detox-gettext-tests later to maint).
   (merge 28e29ee38b jc/doc-format-patch-clarify later to maint).
   (merge fc12b6fdde fm/user-manual-use-preface later to maint).
   (merge dba94e3a85 cc/test-helper-bloom-usage-fix later to maint).
   (merge 61a7660516 hn/reftable-tables-doc-update later to maint).
   (merge 81ed96a9b2 jt/fetch-pack-request-fix later to maint).
   (merge 151b6c2dd7 jc/doc-do-not-capitalize-clarification later to maint).
   (merge 9160068ac6 js/access-nul-emulation-on-windows later to maint).
   (merge 7a14acdbe6 po/diff-patch-doc later to maint).
   (merge f91371b948 pw/patience-diff-clean-up later to maint).
   (merge 3a7f0908b6 mt/clean-clean later to maint).
   (merge d4e2d15a8b ab/streaming-simplify later to maint).
   (merge 0e59f7ad67 ah/merge-ort-i18n later to maint).
   (merge e6f68f62e0 ls/typofix later to maint).