Documentation/RelNotes/2.12.0.txt

Git 2.12 Release Notes
======================

Backward compatibility notes.

 * Use of an empty string 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 not scheduled to happen in the upcoming release (yet).

 * The historical argument order "git merge <msg> HEAD <commit>..."
   has been deprecated for quite some time, and will be removed in the
   upcoming release.


Updates since v2.11
-------------------

UI, Workflows & Features

 * Various updates to "git p4".

 * "git p4" didn't interact with the internal of .git directory
   correctly in the modern "git-worktree"-enabled world.

 * "git branch --list" and friends learned "--ignore-case" option to
   optionally sort branches and tags case insensitively.

 * In addition to %(subject), %(body), "log --pretty=format:..."
   learned a new placeholder %(trailers).

 * "git rebase" learned "--quit" option, which allows a user to
   remove the metadata left by an earlier "git rebase" that was
   manually aborted without using "git rebase --abort".

 * "git clone --reference $there --recurse-submodules $super" has been
   taught to guess repositories usable as references for submodules of
   $super that are embedded in $there while making a clone of the
   superproject borrow objects from $there; extend the mechanism to
   also allow submodules of these submodules to borrow repositories
   embedded in these clones of the submodules embedded in the clone of
   the superproject.

 * Porcelain scripts written in Perl are getting internationalized.

 * "git merge --continue" has been added as a synonym to "git commit"
   to conclude a merge that has stopped due to conflicts.

 * Finer-grained control of what protocols are allowed for transports
   during clone/fetch/push have been enabled via a new configuration
   mechanism.

 * "git shortlog" learned "--committer" option to group commits by
   committer, instead of author.

 * GitLFS integration with "git p4" has been updated.

 * The isatty() emulation for Windows has been updated to eradicate
   the previous hack that depended on internals of (older) MSVC
   runtime.

 * Some platforms no longer understand "latin-1" that is still seen in
   the wild in e-mail headers; replace them with "iso-8859-1" that is
   more widely known when conversion fails from/to it.
   (merge df3755888b jc/latin-1 later to maint).


Performance, Internal Implementation, Development Support etc.

 * Commands that operate on a log message and add lines to the trailer
   blocks, such as "format-patch -s", "cherry-pick (-x|-s)", and
   "commit -s", have been taught to use the logic of and share the
   code with "git interpret-trailer".

 * The default Travis-CI configuration specifies newer P4 and GitLFS.

 * The "fast hash" that had disastrous performance issues in some
   corner cases has been retired from the internal diff.

 * The character width table has been updated to match Unicode 9.0

 * Update the procedure to generate "tags" for developer support.
   (merge 046e4c1c09 jk/make-tags-find-sources-tweak later to maint).

 * The codeflow of setting NOATIME and CLOEXEC on file descriptors Git
   opens has been simplified.
   (merge b4d065df03 jc/git-open-cloexec later to maint).

 * "git diff" and its family had two experimental heuristics to shift
   the contents of a hunk to make the patch easier to read.  One of
   them turns out to be better than the other, so leave only the
   "--indent-heuristic" option and remove the other one.
   (merge 3cde4e02ee jc/retire-compaction-heuristics later to maint).

 * A new submodule helper "git submodule embedgitdirs" to make it
   easier to move embedded .git/ directory for submodules in a
   superproject to .git/modules/ (and point the latter with the former
   that is turned into a "gitdir:" file) has been added.


Also contains various documentation updates and code clean-ups.

Fixes since v2.10
-----------------

Unless otherwise noted, all the fixes since v2.9 in the maintenance
track are contained in this release (see the maintenance releases'
notes for details).

 * We often decide if a session is interactive by checking if the
   standard I/O streams are connected to a TTY, but isatty() that
   comes with Windows incorrectly returned true if it is used on NUL
   (i.e. an equivalent to /dev/null).  This has been fixed.

 * "git svn" did not work well with path components that are "0", and
   some configuration variable it uses were not documented.
   (merge ea9a93dcc2 ew/svn-fixes later to maint).

 * "git rev-parse --symbolic" failed with a more recent notation like
   "HEAD^-1" and "HEAD^!".

 * An empty directory in a working tree that can simply be nuked used
   to interfere while merging or cherry-picking a change to create a
   submodule directory there, which has been fixed..

 * The code in "git push" to compute if any commit being pushed in the
   superproject binds a commit in a submodule that hasn't been pushed
   out was overly inefficient, making it unusable even for a small
   project that does not have any submodule but have a reasonable
   number of refs.

 * "git push --dry-run --recurse-submodule=on-demand" wasn't
   "--dry-run" in the submodules.

 * The output from "git worktree list" was made in readdir() order,
   and was unstable.

 * mergetool.<tool>.trustExitCode configuration variable did not apply
   to built-in tools, but now it does.

 * "git p4" LFS support was broken when LFS stores an empty blob.

 * A corner case in merge-recursive regression that crept in
   during 2.10 development cycle has been fixed.

 * Transport with dumb http can be fooled into following foreign URLs
   that the end user does not intend to, especially with the server
   side redirects and http-alternates mechanism, which can lead to
   security issues.  Tighten the redirection and make it more obvious
   to the end user when it happens.

 * Update the error messages from the dumb-http client when it fails
   to obtain loose objects; we used to give sensible error message
   only upon 404 but we now forbid unexpected redirects that needs to
   be reported with something sensible.

 * When diff.renames configuration is on (and with Git 2.9 and later,
   it is enabled by default, which made it worse), "git stash"
   misbehaved if a file is removed and another file with a very
   similar content is added.

 * "git diff --no-index" did not take "--no-abbrev" option.

 * "git difftool --dir-diff" had a minor regression when started from
   a subdirectory, which has been fixed.

 * "git commit --allow-empty --only" (no pathspec) with dirty index
   ought to be an acceptable way to create a new commit that does not
   change any paths, but it was forbidden, perhaps because nobody
   needed it so far.

 * Git 2.11 had a minor regression in "merge --ff-only" that competed
   with another process that simultanously attempted to update the
   index. We used to explain what went wrong with an error message,
   but the new code silently failed.  The error message has been
   resurrected.

 * A pathname that begins with "//" or "\\" on Windows is special but
   path normalization logic was unaware of it.

 * "git pull --rebase", when there is no new commits on our side since
   we forked from the upstream, should be able to fast-forward without
   invoking "git rebase", but it didn't.

 * The way to specify hotkeys to "xxdiff" that is used by "git
   mergetool" has been modernized to match recent versions of xxdiff.

 * Unlike "git am --abort", "git cherry-pick --abort" moved HEAD back
   to where cherry-pick started while picking multiple changes, when
   the cherry-pick stopped to ask for help from the user, and the user
   did "git reset --hard" to a different commit in order to re-attempt
   the operation.

 * Code cleanup in shallow boundary computation.

 * A recent update to receive-pack to make it easier to drop garbage
   objects made it clear that GIT_ALTERNATE_OBJECT_DIRECTORIES cannot
   have a pathname with a colon in it (no surprise!), and this in turn
   made it impossible to push into a repository at such a path.  This
   has been fixed by introducing a quoting mechanism used when
   appending such a path to the colon-separated list.

 * The function usage_msg_opt() has been updated to say "fatal:"
   before the custom message programs give, when they want to die
   with a message about wrong command line options followed by the
   standard usage string.

 * "git index-pack --stdin" needs an access to an existing repository,
   but "git index-pack file.pack" to generate an .idx file that
   corresponds to a packfile does not.

 * Fix for NDEBUG builds.

 * A lazy "git push" without refspec did not internally use a fully
   specified refspec to perform 'current', 'simple', or 'upstream'
   push, causing unnecessary "ambiguous ref" errors.

 * "git p4" misbehaved when swapping a directory and a symbolic link.

 * Even though an fix was attempted in Git 2.9.3 days, but running
   "git difftool --dir-diff" from a subdirectory never worked. This
   has been fixed.

 * "git p4" that tracks multile p4 paths imported a single changelist
   that touches files in these multiple paths as one commit, followed
   by many empty commits.  This has been fixed.

 * A potential but unlikely buffer overflow in Windows port has been
   fixed.

 * When the http server gives an incomplete response to a smart-http
   rpc call, it could lead to client waiting for a full response that
   will never come.  Teach the client side to notice this condition
   and abort the transfer.

 * Compression setting for producing packfiles were spread across
   three codepaths, one of which did not honor any configuration.
   Unify these so that all of them honor core.compression and
   pack.compression variables the same way.
   (merge 8de7eeb54b jc/compression-config later to maint).

 * "git fast-import" sometimes mishandled while rebalancing notes
   tree, which has been fixed.
   (merge 405d7f4af6 mh/fast-import-notes-fix-new later to maint).

 * Recent update to the default abbreviation length that auto-scales
   lacked documentation update, which has been corrected.
   (merge 48d5014dd4 jc/abbrev-autoscale-config later to maint).

 * Leakage of lockfiles in the config subsystem has been fixed.
   (merge c06fa62dfc nd/config-misc-fixes later to maint).

 * Other minor doc, test and build updates and code cleanups.
   (merge f2627d9b19 sb/submodule-config-cleanup later to maint).