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Linux: Git 0.99.7 Released, Looking Ahead

September 19, 2005 - 9:17am
Submitted by Jeremy on September 19, 2005 - 9:17am.
Linux news

Git 0.99.7 was released by git maintainer Junio Hamano [story], including several bug fixes and a few new features including enhanced merging. "People found interesting cases where the 'stupid' three-way merge mechanism does the wrong thing without noticing," Junio noted. "We have two new merge algorithms by Daniel and Fredrik that attempt to do better in such cases." The release announcement was followed by a todo list laying a roadmap for future git development, and an eventual 1.0 release.

Development of the git directory content manager was begun by Linus Torvalds in early April of 2005 [story], quickly following the announcement that BitKeeper would no longer be freely available to kernel developers [story]. Git rapidly evolved with the help of an active developer community, quickly enough that when the 2.6.12 kernel was released two months later it was already being managed by git [story].


From: Junio C Hamano [email blocked]
To:  git
Subject: [ANNOUNCE] GIT 0.99.7
Date:	Sun, 18 Sep 2005 16:37:10 -0700

I am hoping that sending this out to the kernel list is not
considered too much of useless spamming, but I promise I
wouldn't do thit next time for 0.99.8, if I hear from somebody
not to.

Here comes GIT 0.99.7

--

Done in 0.99.7
==============

Organization
~~~~~~~~~~~~

Some commands and most scripts are renamed for consistency.

  - We have an official standard terminology list [*1*].  To
    match this, commands that operate on index files now have
    'index' instead of 'cache' in their names, and ones that
    download are called 'fetch' instead of 'pull'.

  - We used to install most of the commands that happen to be
    implemented as scripts as 'git-*-script', which was
    cumbersome to remember and type unless you always used 'git'
    wrapper.  They lost '-script' suffix from their names.

For now, we install synonyms as symbolic links so that old
names continue to work, but they are planned to be removed in
0.99.8 (or later if there are enough objections on the list --
so far I have heard none).

Also ancient environment variables [*2*] are not supported
anymore.


New Features and Commands
~~~~~~~~~~~~~~~~~~~~~~~~~

Downloaders that are not fully git aware have been taught about
the mechanism to borrow objects from other repositories via
objects/info/alternates the server side may be using.  'git
fetch' and 'git pull' commands over rsync and http transport
should be able to handle such repositories [*3*].

People found interesting cases where the 'stupid' three-way
merge mechanism does the wrong thing without noticing.  We have
two new merge algorithms by Daniel and Fredrik that attempt to
do better in such cases.  A new 'git merge' command has been
introduced to make it easier to experiment with and choose among
different merge strategies.  Note that 'git pull' still uses the
traditional three-way merge after downloading, but it is
expected to be switched to use 'git merge' sometime in the
future.

Importing from tla archives has been improved and documentated.

'git branch' command acquired '-d' flag to delete a branch that
has already been merged into the current branch.

'git bisect' command is easier to use by logging the earlier
good/bad choices and make it replayable.

'git repack' has -a' flag to pack the whole repository into a
single pack.

'git grep' is a new command to run grep on files 'git' knows
about.


Fixes
~~~~~

* 'git-diff-*' commands used to mark copy/rename incorrectly
  when an (A,B) => (B,C) rename was made.  We said the new B is
  a copy of old A, not a rename of old A.

* When the user exported CDPATH into environment, 'cd' took
  scripts to unexpected places.  Unset it upfront to guard us.

* 'git format-patch' knows about 'git cherry' and skips patches
  already merged upstream.

* hopefully plugged memory leak in diffcore-rename properly.

* commit walkers incorrectly assumed having a commit means we
  have the whole history leading up to it -- which is not true
  if the previous download was interrupted.  As a safety
  measure, we now only trust the commits that are pointed by the
  existing refs.

* 'git rev-list' uses a lot less memory.

* The build should be a bit friendlier to Solaris and Darwin now.

* 'git ssh-{push,pull}' are friendlier to tcsh.

* http transport is nicer to caching proxies.

* 'git daemon' port is registered with IANA.

* Many documentation updates.


[Footnotes]
*1* http://www.kernel.org/pub/software/scm/git/docs/glossary.html

*2* Ancient environment variable names: SHA1_FILE_DIRECTORIES
AUTHOR_DATE AUTHOR_EMAIL AUTHOR_NAME COMMIT_AUTHOR_EMAIL
COMMIT_AUTHOR_NAME SHA1_FILE_DIRECTORY

*3* But not grafts.


From: Junio C Hamano [email blocked] Subject: What to expect after GIT 0.99.7 Date: Sun, 18 Sep 2005 16:40:12 -0700 The GIT To-Do File ================== The latest copy of this document is found at http://kernel.org/git/?p=git/git.git;a=blob;hb=todo;f=TODO Tool Renames Plan ================= - All non-binary commands will lose -script suffix in $(bindir). The source to git-foo will be either git-foo.sh or git-foo.perl in the source tree, and the documentation will be in Documentation/git-foo.txt. - The commands whose names have 'cache' to mean 'index file' will get 'cache' in their names replaced with 'index'. For git-fsck-cache and git-convert-cache, 'cache' will be replaced with 'objects'. - The commit walkers will have 'pull' in their names replaced with 'fetch'. 'git-ssh-push' will become 'git-ssh-upload'. - We continue to follow the convention to name the C source file that contains the main program of 'git-foo' command 'foo.c'. That means we will have 'fsck-objects.c', for example. - At this moment, I am not planning to rename the symbols used in programs, nor any library sources. "cache.h" will stay "cache.h", so does "read-cache.c". "struct cache_entry" and "ce_match_stat()" will keep their names. We _might_ want to rename them in later rounds but not right now. - In 0.99.7, all renamed commands will have symbolic links in $(bindir) so that old names continue to work. These backward compatible names will not appear in documentation. The main documentation, git(7) will talk about the new names but would mention their old names as historical notes. Old environment names defined in gitenv() will also be removed in this release. - In 0.99.8, we do not install these backward compatible symbolic links in $(bindir) anymore. The Makefile will have a target to remove old symlinks from $(DESTDIR)$(bindir) you can run manually to help you clean things up. The timeframe for this is around Oct 1st, but I could be talked into delaying the symlink removal if Porcelain people find this schedule too tight. What to expect after 0.99.7 =========================== This is written in a form of to-do list for me, so if I say "accept patch", it means I do not currently plan to do that myself. People interested in seeing it materialize please take a hint. Documentation ------------- * Accept patches from people who actually have done CVS migration and update the cvs-migration documentation. Link the documentation from the main git.txt page. * Accept patches from people who were hit by shiny blue bat to update the SubmittingPatches. * Talk about using rsync just once at the beginning when initializing a remote repository so that local packs do not need to be expanded. I personally do not think we need tool support for this (but see below about optimized cloning). * Maybe update tutorial with a toy project that involves two or three developers.. * Update tutorial to cover setting up repository hooks to do common tasks. * Accept patches to finish missing docs. Technical (heavier) ------------------- * Tony Luck reported an unfortunate glitch in the 3-way merge. Encourage discussions to come up with a not-so-expensive way to catch the kind of ambiguities that led to his misery. [Deathmatch between Daniel's and Fredrik's ongoing.] * HPA has two projects, klibc and klibc-kbuild, that have large set of overlapping files in different paths (i.e. one has many renames from the other). There currently is no way for git to help keep these two trees in sync, merging criss-cross between them. The merge logic should be able to take advantage of rename/copy detection smarts git-diff-* family has. Linus, me, and Daniel outlined a smarter merge strategy for this. Try them out. * We might want to optimize cloning with GIT native transport not to explode the pack, and store it in objects/pack instead. We would need a tool to generate an idx file out of a pack file for this. Also this itself may turn out to be a bad idea, making the set of packs in repositories everybody has different from each other. * Libification. There are many places "run once" mentality is ingrained in the management of basic data structures, which need to be fixed. * Maybe a pack optimizer. * Maybe an Emacs VC backend. Technical (milder) ------------------ * The recent commit walker safety patch may be too cautious and appears to take forever when cloning. This may even be infinitely looping in the code lifted from the old rev-list -- needs to be taken a look at [DONE INITIAL CUT]. * Encourage concrete proposals to commit log message templates we discussed some time ago. * Accept patches for more portability. * strcasestr() in mailinfo. We may need compat/strcasestr.c; this is bugging OpenBSD folks. * Accept patches to cause "read-tree -u" delete a directory when it makes it empty. * Perhaps accept patches to introduce the concept of "patch flow expressed as ref mappings" Josef has been advocating about. * Perhaps accept patches to do undo/redo. * Perhaps accept patch to optionally allow '--fuzz' in 'git-apply'. * Allow 'git apply' to accept GNU diff 2.7 output that forgets to say '\No newline' if both input ends with incomplete lines. * Maybe grok PGP signed text/plain in applymbox as well. * Perhaps a tool to revert a single file to pre-modification state? git-cat-file blob `git-ls-files | grep foo` >foo or git-cat-file blob `git-ls-tree HEAD foo` >foo? What should the command be called? git-revert is taken so is git-checkout. * Enhance "git repack" to not always use --all; this would be handy if the repository contains wagging heads like "pu" in git.git repository. * Internally split the project into non-doc and doc parts; add an extra root for the doc part and merge from it; move the internal doc source to a separate repository, like the +Meta repository; experiment if this results in a reasonable workflow, and document it in howto form if it does. * Make rebase restartable; instead of skipping what cannot be automatically forward ported, leave the conflicts in the work tree, have the user resolve it, and then restart from where it left off. * Output full path in the "git-rev-list --objects" output, not just the basename, and see the improved clustering results in better packing [Tried, but did not work out well]. * Remove obsolete commands [READY]. * Option to limit rename detection for more than N paths [READY]. * Option to show only status and name from diff [READY]. Technical (trivial) ------------------- * 'git add --recursive'? * 'git merge-projects'? * 'git lost-and-found'? Link dangling commits found by fsck-objects under $GIT_DIR/refs/lost-found/. Then show-branch or gitk can be used to find any lost commit. [A feeler patch sent out. Very underwhelming response X-<.] Do not name it /lost+found/; that would probably confuse things that mistake it a mount point (not our code but somebody else's). * Add simple globbing rules to git-show-branch so that I can say 'git show-branch --heads "ko-*"' (ko-master, ko-pu, and ko-rc are in refs/tags/). * We would want test scripts for the relative directory path stuff Linus has been working on. So far, the following commands should be usable with relative directory paths: git-update-index git-ls-files git-diff-files git-diff-index git-diff-tree git-rev-list git-rev-parse * In a freashly created empty repository, `git fetch foo:bar` works OK, but `git checkout bar` afterwards does not (missing `.git/HEAD`).



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