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diff --git a/Documentation/RelNotes-1.5.0.txt b/Documentation/RelNotes-1.5.0.txt new file mode 100644 index 000000000..daf4bdb0d --- /dev/null +++ b/Documentation/RelNotes-1.5.0.txt @@ -0,0 +1,469 @@ +GIT v1.5.0 Release Notes +======================== + +Old news +-------- + +This section is for people who are upgrading from ancient +versions of git. Although all of the changes in this section +happened before the current v1.4.4 release, they are summarized +here in the v1.5.0 release notes for people who skipped earlier +versions. + +As of git v1.5.0 there are some optional features that changes +the repository to allow data to be stored and transferred more +efficiently. These features are not enabled by default, as they +will make the repository unusable with older versions of git. +Specifically, the available options are: + + - There is a configuration variable core.legacyheaders that + changes the format of loose objects so that they are more + efficient to pack and to send out of the repository over git + native protocol, since v1.4.2. However, loose objects + written in the new format cannot be read by git older than + that version; people fetching from your repository using + older clients over dumb transports (e.g. http) using older + versions of git will also be affected. + + To let git use the new loose object format, you have to + set core.legacyheaders to false. + + - Since v1.4.3, configuration repack.usedeltabaseoffset allows + packfile to be created in more space efficient format, which + cannot be read by git older than that version. + + To let git use the new format for packfiles, you have to + set repack.usedeltabaseoffset to true. + +The above two new features are not enabled by default and you +have to explicitly ask for them, because they make repositories +unreadable by older versions of git, and in v1.5.0 we still do +not enable them by default for the same reason. We will change +this default probably 1 year after 1.4.2's release, when it is +reasonable to expect everybody to have new enough version of +git. + + - 'git pack-refs' appeared in v1.4.4; this command allows tags + to be accessed much more efficiently than the traditional + 'one-file-per-tag' format. Older git-native clients can + still fetch from a repository that packed and pruned refs + (the server side needs to run the up-to-date version of git), + but older dumb transports cannot. Packing of refs is done by + an explicit user action, either by use of "git pack-refs + --prune" command or by use of "git gc" command. + + - 'git -p' to paginate anything -- many commands do pagination + by default on a tty. Introduced between v1.4.1 and v1.4.2; + this may surprise old timers. + + - 'git archive' superseded 'git tar-tree' in v1.4.3; + + - 'git cvsserver' was new invention in v1.3.0; + + - 'git repo-config', 'git grep', 'git rebase' and 'gitk' were + seriously enhanced during v1.4.0 timeperiod. + + - 'gitweb' became part of git.git during v1.4.0 timeperiod and + seriously modified since then. + + - reflog is an v1.4.0 invention. This allows you to name a + revision that a branch used to be at (e.g. "git diff + master@{yesterday} master" allows you to see changes since + yesterday's tip of the branch). + + +Updates in v1.5.0 since v1.4.4 series +------------------------------------- + +* Index manipulation + + - git-add is to add contents to the index (aka "staging area" + for the next commit), whether the file the contents happen to + be is an existing one or a newly created one. + + - git-add without any argument does not add everything + anymore. Use 'git-add .' instead. Also you can add + otherwise ignored files with an -f option. + + - git-add tries to be more friendly to users by offering an + interactive mode ("git-add -i"). + + - git-commit <path> used to refuse to commit if <path> was + different between HEAD and the index (i.e. update-index was + used on it earlier). This check was removed. + + - git-rm is much saner and safer. It is used to remove paths + from both the index file and the working tree, and makes sure + you are not losing any local modification before doing so. + + - git-reset <tree> <paths>... can be used to revert index + entries for selected paths. + + - git-update-index is much less visible. Many suggestions to + use the command in git output and documentation have now been + replaced by simpler commands such as "git add" or "git rm". + + +* Repository layout and objects transfer + + - The data for origin repository is stored in the configuration + file $GIT_DIR/config, not in $GIT_DIR/remotes/, for newly + created clones. The latter is still supported and there is + no need to convert your existing repository if you are + already comfortable with your workflow with the layout. + + - git-clone always uses what is known as "separate remote" + layout for a newly created repository with a working tree. + + A repository with the separate remote layout starts with only + one default branch, 'master', to be used for your own + development. Unlike the traditional layout that copied all + the upstream branches into your branch namespace (while + renaming their 'master' to your 'origin'), the new layout + puts upstream branches into local "remote-tracking branches" + with their own namespace. These can be referenced with names + such as "origin/$upstream_branch_name" and are stored in + .git/refs/remotes rather than .git/refs/heads where normal + branches are stored. + + This layout keeps your own branch namespace less cluttered, + avoids name collision with your upstream, makes it possible + to automatically track new branches created at the remote + after you clone from it, and makes it easier to interact with + more than one remote repository (you can use "git remote" to + add other repositories to track). There might be some + surprises: + + * 'git branch' does not show the remote tracking branches. + It only lists your own branches. Use '-r' option to view + the tracking branches. + + * If you are forking off of a branch obtained from the + upstream, you would have done something like 'git branch + my-next next', because traditional layout dropped the + tracking branch 'next' into your own branch namespace. + With the separate remote layout, you say 'git branch next + origin/next', which allows you to use the matching name + 'next' for your own branch. It also allows you to track a + remote other than 'origin' (i.e. where you initially cloned + from) and fork off of a branch from there the same way + (e.g. "git branch mingw j6t/master"). + + Repositories initialized with the traditional layout continue + to work. + + - New branches that appear on the origin side after a clone is + made are also tracked automatically. This is done with an + wildcard refspec "refs/heads/*:refs/remotes/origin/*", which + older git does not understand, so if you clone with 1.5.0, + you would need to downgrade remote.*.fetch in the + configuration file to specify each branch you are interested + in individually if you plan to fetch into the repository with + older versions of git (but why would you?). + + - Similarly, wildcard refspec "refs/heads/*:refs/remotes/me/*" + can be given to "git-push" command to update the tracking + branches that is used to track the repository you are pushing + from on the remote side. + + - git-branch and git-show-branch know remote tracking branches + (use the command line switch "-r" to list only tracked branches). + + - git-push can now be used to delete a remote branch or a tag. + This requires the updated git on the remote side (use "git + push <remote> :refs/heads/<branch>" to delete "branch"). + + - git-push more aggressively keeps the transferred objects + packed. Earlier we recommended to monitor amount of loose + objects and repack regularly, but you should repack when you + accumulated too many small packs this way as well. Updated + git-count-objects helps you with this. + + - git-fetch also more aggressively keeps the transferred objects + packed. This behavior of git-push and git-fetch can be + tweaked with a single configuration transfer.unpacklimit (but + usually there should not be any need for a user to tweak it). + + - A new command, git-remote, can help you manage your remote + tracking branch definitions. + + - You may need to specify explicit paths for upload-pack and/or + receive-pack due to your ssh daemon configuration on the + other end. This can now be done via remote.*.uploadpack and + remote.*.receivepack configuration. + + +* Bare repositories + + - Certain commands change their behavior in a bare repository + (i.e. a repository without associated working tree). We use + a fairly conservative heuristic (if $GIT_DIR is ".git", or + ends with "/.git", the repository is not bare) to decide if a + repository is bare, but "core.bare" configuration variable + can be used to override the heuristic when it misidentifies + your repository. + + - git-fetch used to complain updating the current branch but + this is now allowed for a bare repository. So is the use of + 'git-branch -f' to update the current branch. + + - Porcelain-ish commands that require a working tree refuses to + work in a bare repository. + + +* Reflog + + - Reflog records the history from the view point of the local + repository. In other words, regardless of the real history, + the reflog shows the history as seen by one particular + repository (this enables you to ask "what was the current + revision in _this_ repository, yesterday at 1pm?"). This + facility is enabled by default for repositories with working + trees, and can be accessed with the "branch@{time}" and + "branch@{Nth}" notation. + + - "git show-branch" learned showing the reflog data with the + new -g option. "git log" has -g option to view reflog + entries in a more verbose manner. + + - git-branch knows how to rename branches and moves existing + reflog data from the old branch to the new one. + + - In addition to the reflog support in v1.4.4 series, HEAD + reference maintains its own log. "HEAD@{5.minutes.ago}" + means the commit you were at 5 minutes ago, which takes + branch switching into account. If you want to know where the + tip of your current branch was at 5 minutes ago, you need to + explicitly say its name (e.g. "master@{5.minutes.ago}") or + omit the refname altogether i.e. "@{5.minutes.ago}". + + - The commits referred to by reflog entries are now protected + against pruning. The new command "git reflog expire" can be + used to truncate older reflog entries and entries that refer + to commits that have been pruned away previously with older + versions of git. + + Existing repositories that have been using reflog may get + complaints from fsck-objects and may not be able to run + git-repack, if you had run git-prune from older git; please + run "git reflog expire --stale-fix --all" first to remove + reflog entries that refer to commits that are no longer in + the repository when that happens. + + +* Crufts removal + + - We used to say "old commits are retrievable using reflog and + 'master@{yesterday}' syntax as long as you haven't run + git-prune". We no longer have to say the latter half of the + above sentence, as git-prune does not remove things reachable + from reflog entries. + + - There is a toplevel garbage collector script, 'git-gc', that + runs periodic cleanup functions, including 'git-repack -a -d', + 'git-reflog expire', 'git-pack-refs --prune', and 'git-rerere + gc'. + + - The output from fsck ("fsck-objects" is called just "fsck" + now, but the old name continues to work) was needlessly + alarming in that it warned missing objects that are reachable + only from dangling objects. This has been corrected and the + output is much more useful. + + +* Detached HEAD + + - You can use 'git-checkout' to check out an arbitrary revision + or a tag as well, instead of named branches. This will + dissociate your HEAD from the branch you are currently on. + + A typical use of this feature is to "look around". E.g. + + $ git checkout v2.6.16 + ... compile, test, etc. + $ git checkout v2.6.17 + ... compile, test, etc. + + - After detaching your HEAD, you can go back to an existing + branch with usual "git checkout $branch". Also you can + start a new branch using "git checkout -b $newbranch" to + start a new branch at that commit. + + - You can even pull from other repositories, make merges and + commits while your HEAD is detached. Also you can use "git + reset" to jump to arbitrary commit, while still keeping your + HEAD detached. + + Remember that a detached state is volatile, i.e. it will be forgotten + as soon as you move away from it with the checkout or reset command, + unless a branch is created from it as mentioned above. It is also + possible to rescue a lost detached state from the HEAD reflog. + + +* Packed refs + + - Repositories with hundreds of tags have been paying large + overhead, both in storage and in runtime, due to the + traditional one-ref-per-file format. A new command, + git-pack-refs, can be used to "pack" them in more efficient + representation (you can let git-gc do this for you). + + - Clones and fetches over dumb transports are now aware of + packed refs and can download from repositories that use + them. + + +* Configuration + + - configuration related to color setting are consolidated under + color.* namespace (older diff.color.*, status.color.* are + still supported). + + - 'git-repo-config' command is accessible as 'git-config' now. + + +* Updated features + + - git-describe uses better criteria to pick a base ref. It + used to pick the one with the newest timestamp, but now it + picks the one that is topologically the closest (that is, + among ancestors of commit C, the ref T that has the shortest + output from "git-rev-list T..C" is chosen). + + - git-describe gives the number of commits since the base ref + between the refname and the hash suffix. E.g. the commit one + before v2.6.20-rc6 in the kernel repository is: + + v2.6.20-rc5-306-ga21b069 + + which tells you that its object name begins with a21b069, + v2.6.20-rc5 is an ancestor of it (meaning, the commit + contains everything -rc5 has), and there are 306 commits + since v2.6.20-rc5. + + - git-describe with --abbrev=0 can be used to show only the + name of the base ref. + + - git-blame learned a new option, --incremental, that tells it + to output the blames as they are assigned. A sample script + to use it is also included as contrib/blameview. + + - git-blame starts annotating from the working tree by default. + + +* Less external dependency + + - We no longer require the "merge" program from the RCS suite. + All 3-way file-level merges are now done internally. + + - The original implementation of git-merge-recursive which was + in Python has been removed; we have a C implementation of it + now. + + - git-shortlog is no longer a Perl script. It no longer + requires output piped from git-log; it can accept revision + parameters directly on the command line. + + +* I18n + + - We have always encouraged the commit message to be encoded in + UTF-8, but the users are allowed to use legacy encoding as + appropriate for their projects. This will continue to be the + case. However, a non UTF-8 commit encoding _must_ be + explicitly set with i18n.commitencoding in the repository + where a commit is made; otherwise git-commit-tree will + complain if the log message does not look like a valid UTF-8 + string. + + - The value of i18n.commitencoding in the originating + repository is recorded in the commit object on the "encoding" + header, if it is not UTF-8. git-log and friends notice this, + and reencodes the message to the log output encoding when + displaying, if they are different. The log output encoding + is determined by "git log --encoding=<encoding>", + i18n.logoutputencoding configuration, or i18n.commitencoding + configuration, in the decreasing order of preference, and + defaults to UTF-8. + + - Tools for e-mailed patch application now default to -u + behavior; i.e. it always re-codes from the e-mailed encoding + to the encoding specified with i18n.commitencoding. This + unfortunately forces projects that have happily been using a + legacy encoding without setting i18n.commitencoding to set + the configuration, but taken with other improvement, please + excuse us for this very minor one-time inconvenience. + + +* e-mailed patches + + - See the above I18n section. + + - git-format-patch now enables --binary without being asked. + git-am does _not_ default to it, as sending binary patch via + e-mail is unusual and is harder to review than textual + patches and it is prudent to require the person who is + applying the patch to explicitly ask for it. + + - The default suffix for git-format-patch output is now ".patch", + not ".txt". This can be changed with --suffix=.txt option, + or setting the config variable "format.suffix" to ".txt". + + +* Foreign SCM interfaces + + - git-svn now requires the Perl SVN:: libraries, the + command-line backend was too slow and limited. + + - the 'commit' subcommand of git-svn has been renamed to + 'set-tree', and 'dcommit' is the recommended replacement for + day-to-day work. + + - git fast-import backend. + + +* User support + + - Quite a lot of documentation updates. + + - Bash completion scripts have been updated heavily. + + - Better error messages for often used Porcelainish commands. + + - Git GUI. This is a simple Tk based graphical interface for + common Git operations. + + +* Sliding mmap + + - We used to assume that we can mmap the whole packfile while + in use, but with a large project this consumes huge virtual + memory space and truly huge ones would not fit in the + userland address space on 32-bit platforms. We now mmap huge + packfile in pieces to avoid this problem. + + +* Shallow clones + + - There is a partial support for 'shallow' repositories that + keeps only recent history. A 'shallow clone' is created by + specifying how deep that truncated history should be + (e.g. "git clone --depth 5 git://some.where/repo.git"). + + Currently a shallow repository has number of limitations: + + - Cloning and fetching _from_ a shallow clone are not + supported (nor tested -- so they might work by accident but + they are not expected to). + + - Pushing from nor into a shallow clone are not expected to + work. + + - Merging inside a shallow repository would work as long as a + merge base is found in the recent history, but otherwise it + will be like merging unrelated histories and may result in + huge conflicts. + + but this would be more than adequate for people who want to + look at near the tip of a big project with a deep history and + send patches in e-mail format. |