fetch-pack: avoid quadratic behavior in rev_list_push

[git/gitweb.git] / Documentation / RelNotes / 1.8.4.txt

Git v1.8.4 Release Notes
========================

Updates since v1.8.3
--------------------

Foreign interfaces, subsystems and ports.

 * Git-gui has been updated to its 0.18.0 version.

 * MediaWiki remote helper (in contrib/) has been updated to use the
   credential helper interface from Git.pm.

 * Update build for Cygwin 1.[57].  Torsten Bögershausen reports that
   this is fine with Cygwin 1.7 ($gmane/225824) so let's try moving it
   ahead.

 * The credential helper to talk to keychain on OS X (in contrib/) has
   been updated to kick in not just when talking http/https but also
   imap(s) and smtp.

 * Remote transport helper has been updated to report errors and
   maintain ref hierarchy used to keep track of its own state better.

 * With "export" remote-helper protocol, (1) a push that tries to
   update a remote ref whose name is different from the pushing side
   does not work yet, and (2) the helper may not know how to do
   --dry-run; these problematic cases are disabled for now.

 * git-remote-hg/bzr (in contrib/) updates.

 * git-remote-mw (in contrib/) hints users to check the certificate,
   when https:// connection failed.


UI, Workflows & Features

 * Various subcommands of "git submodule" refused to run from anywhere
   other than the top of the working tree of the superproject, but
   they have been taught to let you run from a subdirectory.

 * "git diff" learned a mode that ignores hunks whose change consists
   only of additions and removals of blank lines, which is the same as
   "diff -B" (ignore blank lines) of GNU diff.

 * "git rm" gives a single message followed by list of paths to report
   multiple paths that cannot be removed.

 * "git rebase" can be told with ":/look for this string" syntax commits
   to replay the changes onto and where the work to be replayed begins.

 * Many tutorials teach users to set "color.ui" to "auto" as the first
   thing after you set "user.name/email" to introduce yourselves to
   Git.  Now the variable defaults to "auto".

 * On Cygwin, "cygstart" is now recognised as a possible way to start
   a web browser (used in "help -w" and "instaweb" among others).

### * "git status" learned status.branch and status.short configuration
###   variables to use --branch and --short options by default (override
###   with --no-branch and --no-short options from the command line).

 * "git cmd <name>", when <name> happens to be a 40-hex string,
   directly uses the 40-hex string as an object name, even if a ref
   "refs/<some hierarchy>/<name>" exists.  This disambiguation order
   is unlikely to change, but we should warn about the ambiguity just
   like we warn when more than one refs/ hierachies share the same
   name.

 * "git rebase" learned "--[no-]autostash" option to save local
   changes instead of refusing to run (to which people's normal
   response was to stash them and re-run).  This introduced a corner
   case breakage to "git am --abort" but it has been fixed.

 * Instead of typing four capital letters "HEAD", you can say "@" now,
   e.g. "git log @".

 * "check-ignore" (new feature since 1.8.2) has been updated to work
   more like "check-attr" over bidi-pipes.

 * "git describe" learned "--first-parent" option to limit its closest
   tagged commit search to the first-parent chain.

 * "git merge foo" that might have meant "git merge origin/foo" is
   diagnosed with a more informative error message.

 * "git log -L<line>,<range>:<filename>" has been added.  This may
   still have leaks and rough edges, though.

 * We used the approxidate() parser for "--expire=<timestamp>" options
   of various commands, but it is better to treat --expire=all and
   --expire=now a bit more specially than using the current timestamp.
   "git gc" and "git reflog" have been updated with a new parsing
   function for expiry dates.

 * Updates to completion (both bash and zsh) helpers.

 * The behaviour of the "--chain-reply-to" option of "git send-email"
   have changed at 1.7.0, and we added a warning/advice message to
   help users adjust to the new behaviour back then, but we kept it
   around for too long.  The message has finally been removed.

 * "git fetch origin master" unlike "git fetch origin" or "git fetch"
   did not update "refs/remotes/origin/master"; this was an early
   design decision to keep the update of remote tracking branches
   predictable, but in practice it turns out that people find it more
   convenient to opportunistically update them whenever we have a
   chance, and we have been updating them when we run "git push" which
   already breaks the original "predictability" anyway.

 * The configuration variable core.checkstat was advertised in the
   documentation but the code expected core.statinfo instead.
   For now, we accept both core.checkstat and core.statinfo, but the
   latter will be removed in the longer term.


Performance, Internal Implementation, etc.

 * "git pack-refs" that races with new ref creation or deletion have
   been susceptible to lossage of refs under right conditions, which
   has been tightened up.

 * We read loose and packed rerferences in two steps, but after
   deciding to read a loose ref but before actually opening it to read
   it, another process racing with us can unlink it, which would cause
   us to barf.  The codepath has been updated to retry when such a
   race is detected, instead of outright failing.

 * Uses of the platform fnmatch(3) function (many places in the code,
   matching pathspec, .gitignore and .gitattributes to name a few)
   have been replaced with wildmatch, allowing "foo/**/bar" that would
   match foo/bar, foo/a/bar, foo/a/b/bar, etc.

 * Memory ownership and lifetime rules for what for-each-ref feeds to
   its callbacks have been clarified (in short, "you do not own it, so
   make a copy if you want to keep it").

 * The revision traversal logic to improve culling of irrelevant
   parents while traversing a mergy history has been updated.

 * Some leaks in unpack-trees (used in merge, cherry-pick and other
   codepaths) have been plugged.

 * The codepath to read from marks files in fast-import/export did not
   have to accept anything but 40-hex representation of the object
   name.  Further, fast-export did not need full in-core object
   representation to have parsed wen reading from them.  These
   codepaths have been optimized by taking advantage of these access
   patterns.

 * Object lookup logic, when the object hashtable starts to become
   crowded, has been optimized.

 * When TEST_OUTPUT_DIRECTORY setting is used, it was handled somewhat
   inconsistently between the test framework and t/Makefile, and logic
   to summarize the results looked at a wrong place.

 * "git clone" uses a lighter-weight implementation when making sure
   that the history behind refs are complete.

 * Many warnings from sparse source checker in compat/ area has been
   squelched.

 * The code to reading and updating packed-refs file has been updated,
   correcting corner case bugs.


Also contains various documentation updates and code clean-ups.


Fixes since v1.8.3
------------------

Unless otherwise noted, all the fixes since v1.8.3 in the maintenance
track are contained in this release (see release notes to them for
details).

 * "git name-rev --refs=tags/v*" were forbidden, which was a bit
   inconvenient (you had to give a pattern to match refs fully, like
   --refs=refs/tags/v*).
   (merge 98c5c4a nk/name-rev-abbreviated-refs later to maint).

 * "git apply" parsed patches that add new files, generated by
   programs other than Git, incorrectly.  This is an old breakage in
   v1.7.11 and will need to be merged down to the maintanance tracks.
   (merge 212eb96 tr/maint-apply-non-git-patch-parsefix later to maint).

 * Older cURL wanted piece of memory we call it with to be stable, but
   we updated the auth material after handing it to a call.
   (merge a94cf2c bc/http-keep-memory-given-to-curl later to maint).

 * "git pull" into nothing trashed "local changes" that were in the
   index, and this avoids it.
   (merge b4dc085 jk/pull-into-dirty-unborn later to maint).

 * Many "git submodule" operations do not work on a submodule at a
   path whose name is not in ASCII.
   (merge bed9470 fg/submodule-non-ascii-path later to maint).

 * "cherry-pick" had a small leak in an error codepath.
   (merge 706728a fc/sequencer-plug-leak later to maint).

 * Logic used by git-send-email to suppress cc mishandled names like
   "A U. Thor" <author@example.xz>, where the human readable part
   needs to be quoted (the user input may not have the double quotes
   around the name, and comparison was done between quoted and
   unquoted strings).  It also mishandled names that need RFC2047
   quoting.
   (merge 1495266 mt/send-email-cc-match-fix later to maint).

 * Call to discard_cache/discard_index (used when we use different
   contents of the index in-core, in many operations like commit,
   apply, and merge) used to leak memory that held the array of index
   entries, which has been plugged.
   (merge a0fc4db rs/discard-index-discard-array later to maint).

 * "gitweb" forgot to clear a global variable $search_regexp upon each
   request, mistakenly carrying over the previous search to a new one
   when used as a persistent CGI.
   (merge ca7a5dc cm/gitweb-project-list-persistent-cgi-fix later to maint).

 * The wildmatch engine did not honor WM_CASEFOLD option correctly.
   (merge b79c0c3 ar/wildmatch-foldcase later to maint).

 * "git log -c --follow $path" segfaulted upon hitting the commit that
   renamed the $path being followed.
   (merge 46ec510 cb/log-follow-with-combined later to maint).

 * When a reflog notation is used for implicit "current branch", we
   did not say which branch and worse said "branch ''".
   (merge 305ebea rr/die-on-missing-upstream later to maint).

 * "difftool --dir-diff" did not copy back changes made by the
   end-user in the diff tool backend to the working tree in some
   cases.
   (merge 32eaf1d ks/difftool-dir-diff-copy-fix later to maint).

 * "git push $there HEAD:branch" did not resolve HEAD early enough, so
   it was easy to flip it around while push is still going on and push
   out a branch that the user did not originally intended when the
   command was started.
   (merge 0f075b2 rr/push-head later to maint).

 * The bash prompt code (in contrib/) displayed the name of the branch
   being rebased when "rebase -i/-m/-p" modes are in use, but not the
   plain vanilla "rebase".
   (merge 1306321 fc/show-branch-in-rebase-am later to maint).

 * Handling of negative exclude pattern for directories "!dir" was
   broken in the update to v1.8.3.
   (merge c3c327d kb/status-ignored-optim-2 later to maint).

 * zsh prompt script that borrowed from bash prompt script did not
   work due to slight differences in array variable notation between
   these two shells.
   (merge d0583da tg/maint-zsh-svn-remote-prompt later to maint).

 * An entry for "file://" scheme in the enumeration of URL types Git
   can take in the HTML documentation was made into a clickable link
   by mistake.
   (merge 4c32e36 nd/urls-doc-no-file-hyperlink-fix later to maint).

 * "git push --[no-]verify" was not documented.
   (merge 90d32d1 tr/push-no-verify-doc later to maint).

 * Stop installing the git-remote-testpy script that is only used for
   testing.
   (merge 416fda6 fc/makefile later to maint).

 * "git commit --allow-empty-message -m ''" should not start an
   editor.
   (merge 2520677 rs/commit-m-no-edit later to maint).

 * "git merge @{-1}~22" was rewritten to "git merge frotz@{1}~22"
   incorrectly when your previous branch was "frotz" (it should be
   rewritten to "git merge frotz~22" instead).
   (merge 84cf246 jc/strbuf-branchname-fix later to maint).

 * "git diff -c -p" was not showing a deleted line from a hunk when
   another hunk immediately begins where the earlier one ends.
   (merge aac3857 mk/combine-diff-context-horizon-fix later to maint).

 * "git log --ancestry-path A...B" did not work as expected, as it did
   not pay attention to the fact that the merge base between A and B
   was the bottom of the range being specified.
   (merge a765499 kb/ancestry-path-threedots later to maint).

 * Mac OS X does not like to write(2) more than INT_MAX number of
   bytes; work it around by chopping write(2) into smaller pieces.
   (merge 6c642a8 fc/macos-x-clipped-write later to maint).

 * Newer MacOS X encourages the programs to compile and link with
   their CommonCrypto, not with OpenSSL.
   (merge be4c828 da/darwin later to maint).

 * "git clone foo/bar:baz" cannot be a request to clone from a remote
   over git-over-ssh specified in the scp style.  This case is now
   detected and clones from a local repository at "foo/bar:baz".
   (merge 6000334 nd/clone-local-with-colon later to maint).

 * When $HOME is misconfigured to point at an unreadable directory, we
   used to complain and die. Loosen the check.
   (merge 4698c8f jn/config-ignore-inaccessible later to maint).

 * "git subtree" (in contrib/) had one codepath with loose error
   checks to lose data at the remote side.
   (merge 3212d56 jk/subtree-do-not-push-if-split-fails later to maint).

 * "git fetch" into a shallow repository from a repository that does
   not know about the shallow boundary commits (e.g. a different fork
   from the repository the current shallow repository was cloned from)
   did not work correctly.
   (merge 71d5f93 mh/fetch-into-shallow later to maint).

 * "git checkout foo" DWIMs the intended "upstream" and turns it into
   "git checkout -t -b foo remotes/origin/foo". This codepath has been
   updated to correctly take existing remote definitions into account.
   (merge 229177a jh/checkout-auto-tracking later to maint).