struct ref_transaction: add a place for backends to store data

[alt-git.git] / Documentation / RelNotes / 2.15.0.txt

Git 2.15 Release Notes
======================

Backward compatibility notes and other notable changes.

 * Use of an empty string as a pathspec element that is used for
   'everything matches' is still warned and Git asks users to use a
   more explicit '.' for that instead.  The hope is that existing
   users will not mind this change, and eventually the warning can be
   turned into a hard error, upgrading the deprecation into removal of
   this (mis)feature.  That is now scheduled to happen in the upcoming
   release.

 * Git now avoids blindly falling back to ".git" when the setup
   sequence said we are _not_ in Git repository.  A corner case that
   happens to work right now may be broken by a call to die("BUG").
   We've tried hard to locate such cases and fixed them, but there
   might still be cases that need to be addressed--bug reports are
   greatly appreciated.


Updates since v2.14
-------------------

UI, Workflows & Features

 * An example that is now obsolete has been removed from a sample hook,
   and an old example in it that added a sign-off manually has been
   improved to use the interpret-trailers command.

 * The advice message given when "git rebase" stops for conflicting
   changes has been improved.

 * The "rerere-train" script (in contrib/) learned the "--overwrite"
   option to allow overwriting existing recorded resolutions.

 * "git contacts" (in contrib/) now lists the address on the
   "Reported-by:" trailer to its output, in addition to those on
   S-o-b: and other trailers, to make it easier to notify (and thank)
   the original bug reporter.

 * "git rebase", especially when it is run by mistake and ends up
   trying to replay many changes, spent long time in silence.  The
   command has been taught to show progress report when it spends
   long time preparing these many changes to replay (which would give
   the user a chance to abort with ^C).

 * "git merge" learned a "--signoff" option to add the Signed-off-by:
   trailer with the committer's name.

 * "git diff" learned to optionally paint new lines that are the same
   as deleted lines elsewhere differently from genuinely new lines.

 * "git interpret-trailers" learned to take the trailer specifications
   from the command line that overrides the configured values.

 * "git interpret-trailers" has been taught a "--parse" and a few
   other options to make it easier for scripts to grab existing
   trailer lines from a commit log message.

 * "gitweb" shows a link to visit the 'raw' contents of blbos in the
   history overview page.

 * "[gc] rerereResolved = 5.days" used to be invalid, as the variable
   is defined to take an integer counting the number of days.  It now
   is allowed.

 * The code to acquire a lock on a reference (e.g. while accepting a
   push from a client) used to immediately fail when the reference is
   already locked---now it waits for a very short while and retries,
   which can make it succeed if the lock holder was holding it during
   a read-only operation.


Performance, Internal Implementation, Development Support etc.

 * Conversion from uchar[20] to struct object_id continues.

 * Start using selected c99 constructs in small, stable and
   essentialpart of the system to catch people who care about
   older compilers that do not grok them.

 * The filter-process interface learned to allow a process with long
   latency give a "delayed" response.

 * Many uses of comparision callback function the hashmap API uses
   cast the callback function type when registering it to
   hashmap_init(), which defeats the compile time type checking when
   the callback interface changes (e.g. gaining more parameters).
   The callback implementations have been updated to take "void *"
   pointers and cast them to the type they expect instead.

 * Because recent Git for Windows do come with a real msgfmt, the
   build procedure for git-gui has been updated to use it instead of a
   hand-rolled substitute.

 * "git grep --recurse-submodules" has been reworked to give a more
   consistent output across submodule boundary (and do its thing
   without having to fork a separate process).

 * A helper function to read a single whole line into strbuf
   mistakenly triggered OOM error at EOF under certain conditions,
   which has been fixed.
   (merge 642956cf45 rs/strbuf-getwholeline-fix later to maint).

 * The "ref-store" code reorganization continues.

 * "git commit" used to discard the index and re-read from the filesystem
   just in case the pre-commit hook has updated it in the middle; this
   has been optimized out when we know we do not run the pre-commit hook.
   (merge 680ee550d7 kw/commit-keep-index-when-pre-commit-is-not-run later to maint).

 * Updates to the HTTP layer we made recently unconditionally used
   features of libCurl without checking the existence of them, causing
   compilation errors, which has been fixed.  Also migrate the code to
   check feature macros, not version numbers, to cope better with
   libCurl that vendor ships with backported features.

 * The API to start showing progress meter after a short delay has
   been simplified.
   (merge 8aade107dd jc/simplify-progress later to maint).

 * Code clean-up to avoid mixing values read from the .gitmodules file
   and values read from the .git/config file.

 * We used to spend more than necessary cycles allocating and freeing
   piece of memory while writing each index entry out.  This has been
   optimized.

Also contains various documentation updates and code clean-ups.


Fixes since v2.14
-----------------

 * "%C(color name)" in the pretty print format always produced ANSI
   color escape codes, which was an early design mistake.  They now
   honor the configuration (e.g. "color.ui = never") and also tty-ness
   of the output medium.

 * The http.{sslkey,sslCert} configuration variables are to be
   interpreted as a pathname that honors "~[username]/" prefix, but
   weren't, which has been fixed.

 * Numerous bugs in walking of reflogs via "log -g" and friends have
   been fixed.

 * "git commit" when seeing an totally empty message said "you did not
   edit the message", which is clearly wrong.  The message has been
   corrected.

 * When a directory is not readable, "gitweb" fails to build the
   project list.  Work this around by skipping such a directory.

 * Some versions of GnuPG fails to kill gpg-agent it auto-spawned
   and such a left-over agent can interfere with a test.  Work it
   around by attempting to kill one before starting a new test.
   (merge 29ff1f8f74 st/lib-gpg-kill-stray-agent later to maint).

 * A recently added test for the "credential-cache" helper revealed
   that EOF detection done around the time the connection to the cache
   daemon is torn down were flaky.  This was fixed by reacting to
   ECONNRESET and behaving as if we got an EOF.

 * "git log --tag=no-such-tag" showed log starting from HEAD, which
   has been fixed---it now shows nothing.
   (merge 5d34d1ac06 jk/rev-list-empty-input later to maint).

 * The "tag.pager" configuration variable was useless for those who
   actually create tag objects, as it interfered with the use of an
   editor.  A new mechanism has been introduced for commands to enable
   pager depending on what operation is being carried out to fix this,
   and then "git tag -l" is made to run pager by default.
   (merge 595d59e2b5 ma/pager-per-subcommand-action later to maint).

 * "git push --recurse-submodules $there HEAD:$target" was not
   propagated down to the submodules, but now it is.
   (merge c7be7201a7 bw/push-options-recursively-to-submodules later to maint).

 * Commands like "git rebase" accepted the --rerere-autoupdate option
   from the command line, but did not always use it.  This has been
   fixed.
   (merge f826fb799e pw/sequence-rerere-autoupdate later to maint).

 * "git clone --recurse-submodules --quiet" did not pass the quiet
   option down to submodules.
   (merge 03c004c581 bw/clone-recursive-quiet later to maint).

 * Test portability fix for OBSD.
   (merge bed67874e2 rs/obsd-getcwd-workaround later to maint).
   (merge 4c7fda8fc1 rs/t4062-obsd later to maint).

 * Portability fix for OBSD.
   (merge 29c2eda80b rs/in-obsd-basename-dirname-take-const later to maint).

 * "git am -s" has been taught that some input may end with a trailer
   block that is not Signed-off-by: and it should refrain from adding
   an extra blank line before adding a new sign-off in such a case.
   (merge 735285b403 pw/am-signoff later to maint).

 * "git svn" used with "--localtime" option did not compute the tz
   offset for the timestamp in question and instead always used the
   current time, which has been corrected.
   (merge 1adc4b9a58 ur/svn-local-zone later to maint).

 * Memory leak in an error codepath has been plugged.
   (merge 83cd6f9017 rs/fsck-obj-leakfix later to maint).
   (merge 896dca3ab7 rs/unpack-entry-leakfix later to maint).
   (merge 149d8cbb2e rs/win32-syslog-leakfix later to maint).

 * "git stash -u" used the contents of the committed version of the
   ".gitignore" file to decide which paths are ignored, even when the
   file has local changes.  The command has been taught to instead use
   the locally modified contents.

 * bash 4.4 or newer gave a warning on NUL byte in command
   substitution done in "git stash"; this has been squelched.
   (merge 5fc92f8828 kd/stash-with-bash-4.4 later to maint).

 * "git grep -L" and "git grep --quiet -L" reported different exit
   codes; this has been corrected.
   (merge e1f68c66d5 as/grep-quiet-no-match-exit-code-fix later to maint).

 * When handshake with a subprocess filter notices that the process
   asked for an unknown capability, Git did not report what program
   the offending subprocess was running.  This has been corrected.
   (merge d3ba566342 cc/subprocess-handshake-missing-capabilities later to maint).

 * "git apply" that is used as a better "patch -p1" failed to apply a
   taken from a file with CRLF line endings to a file with CRLF line
   endings.  The root cause was because it misused convert_to_git()
   that tried to do "safe-crlf" processing by looking at the index
   entry at the same path, which is a nonsense---in that mode, "apply"
   is not working on the data in (or derived from) the index at all.
   This has been fixed.
   (merge c24f3abace tb/apply-with-crlf later to maint).

 * Killing "git merge --edit" before the editor returns control left
   the repository in a state with MERGE_MSG but without MERGE_HEAD,
   which incorrectly tells the subsequent "git commit" that there was
   a squash merge in progress.  This has been fixed.
   (merge 9d89b35526 mg/killed-merge later to maint).

 * Other minor doc, test and build updates and code cleanups.
   (merge dff2813391 ab/ref-filter-no-contains later to maint).
   (merge f094b89a4d ma/parse-maybe-bool later to maint).
   (merge 974ce8078c mf/no-dashed-subcommands later to maint).
   (merge f81935cc4d jc/perl-git-comment-typofix later to maint).
   (merge 57ea241ef0 rs/t3700-clean-leftover later to maint).
   (merge 39b00fa4d4 jk/drop-sha1-entry-pos later to maint).
   (merge 0b006014c8 jk/hashcmp-memcmp later to maint).
   (merge 1e22a9917b rj/add-chmod-error-message later to maint).
   (merge 881529c846 rs/apply-lose-prefix-length later to maint).
   (merge 6355a76802 rs/find-pack-entry-bisection later to maint).
   (merge de3ce210ed rs/merge-microcleanup later to maint).
   (merge 7f0a02be2f ah/doc-empty-string-is-false later to maint).
   (merge 70ec6bd63b rs/t1002-do-not-use-sum later to maint).
   (merge 2456990dfd sb/sha1-file-cleanup later to maint).
   (merge 2aac933c62 hv/t5526-andand-chain-fix later to maint).
   (merge c8d0c4fe9b sb/submodule-parallel-update later to maint).
   (merge 794b7e1674 mg/format-ref-doc-fix later to maint).
   (merge 24da8a26a9 rs/commit-h-single-parent-cleanup later to maint).
   (merge 4e36907fa3 jk/doc-the-this later to maint).
   (merge 15d1d0951e bc/vcs-svn-cleanup later to maint).
   (merge b8f43b120b jn/vcs-svn-cleanup later to maint).
   (merge 4a4becfb23 jt/doc-pack-objects-fix later to maint).