Documentation / RelNotes-1.5.0.txton commit merge-recursive --renormalize (7610fa5)
   1GIT v1.5.0 Release Notes
   2========================
   3
   4Old news
   5--------
   6
   7This section is for people who are upgrading from ancient
   8versions of git.  Although all of the changes in this section
   9happened before the current v1.4.4 release, they are summarized
  10here in the v1.5.0 release notes for people who skipped earlier
  11versions.
  12
  13As of git v1.5.0 there are some optional features that changes
  14the repository to allow data to be stored and transferred more
  15efficiently.  These features are not enabled by default, as they
  16will make the repository unusable with older versions of git.
  17Specifically, the available options are:
  18
  19 - There is a configuration variable core.legacyheaders that
  20   changes the format of loose objects so that they are more
  21   efficient to pack and to send out of the repository over git
  22   native protocol, since v1.4.2.  However, loose objects
  23   written in the new format cannot be read by git older than
  24   that version; people fetching from your repository using
  25   older clients over dumb transports (e.g. http) using older
  26   versions of git will also be affected.
  27
  28   To let git use the new loose object format, you have to
  29   set core.legacyheaders to false.
  30
  31 - Since v1.4.3, configuration repack.usedeltabaseoffset allows
  32   packfile to be created in more space efficient format, which
  33   cannot be read by git older than that version.
  34
  35   To let git use the new format for packfiles, you have to
  36   set repack.usedeltabaseoffset to true.
  37
  38The above two new features are not enabled by default and you
  39have to explicitly ask for them, because they make repositories
  40unreadable by older versions of git, and in v1.5.0 we still do
  41not enable them by default for the same reason.  We will change
  42this default probably 1 year after 1.4.2's release, when it is
  43reasonable to expect everybody to have new enough version of
  44git.
  45
  46 - 'git pack-refs' appeared in v1.4.4; this command allows tags
  47   to be accessed much more efficiently than the traditional
  48   'one-file-per-tag' format.  Older git-native clients can
  49   still fetch from a repository that packed and pruned refs
  50   (the server side needs to run the up-to-date version of git),
  51   but older dumb transports cannot.  Packing of refs is done by
  52   an explicit user action, either by use of "git pack-refs
  53   --prune" command or by use of "git gc" command.
  54
  55 - 'git -p' to paginate anything -- many commands do pagination
  56   by default on a tty.  Introduced between v1.4.1 and v1.4.2;
  57   this may surprise old timers.
  58
  59 - 'git archive' superseded 'git tar-tree' in v1.4.3;
  60
  61 - 'git cvsserver' was new invention in v1.3.0;
  62
  63 - 'git repo-config', 'git grep', 'git rebase' and 'gitk' were
  64   seriously enhanced during v1.4.0 timeperiod.
  65
  66 - 'gitweb' became part of git.git during v1.4.0 timeperiod and
  67   seriously modified since then.
  68
  69 - reflog is an v1.4.0 invention.  This allows you to name a
  70   revision that a branch used to be at (e.g. "git diff
  71   master@{yesterday} master" allows you to see changes since
  72   yesterday's tip of the branch).
  73
  74
  75Updates in v1.5.0 since v1.4.4 series
  76-------------------------------------
  77
  78* Index manipulation
  79
  80 - git-add is to add contents to the index (aka "staging area"
  81   for the next commit), whether the file the contents happen to
  82   be is an existing one or a newly created one.
  83
  84 - git-add without any argument does not add everything
  85   anymore.  Use 'git-add .' instead.  Also you can add
  86   otherwise ignored files with an -f option.
  87
  88 - git-add tries to be more friendly to users by offering an
  89   interactive mode ("git-add -i").
  90
  91 - git-commit <path> used to refuse to commit if <path> was
  92   different between HEAD and the index (i.e. update-index was
  93   used on it earlier).  This check was removed.
  94
  95 - git-rm is much saner and safer.  It is used to remove paths
  96   from both the index file and the working tree, and makes sure
  97   you are not losing any local modification before doing so.
  98
  99 - git-reset <tree> <paths>... can be used to revert index
 100   entries for selected paths.
 101
 102 - git-update-index is much less visible.  Many suggestions to
 103   use the command in git output and documentation have now been
 104   replaced by simpler commands such as "git add" or "git rm".
 105
 106
 107* Repository layout and objects transfer
 108
 109 - The data for origin repository is stored in the configuration
 110   file $GIT_DIR/config, not in $GIT_DIR/remotes/, for newly
 111   created clones.  The latter is still supported and there is
 112   no need to convert your existing repository if you are
 113   already comfortable with your workflow with the layout.
 114
 115 - git-clone always uses what is known as "separate remote"
 116   layout for a newly created repository with a working tree.
 117
 118   A repository with the separate remote layout starts with only
 119   one default branch, 'master', to be used for your own
 120   development.  Unlike the traditional layout that copied all
 121   the upstream branches into your branch namespace (while
 122   renaming their 'master' to your 'origin'), the new layout
 123   puts upstream branches into local "remote-tracking branches"
 124   with their own namespace. These can be referenced with names
 125   such as "origin/$upstream_branch_name" and are stored in
 126   .git/refs/remotes rather than .git/refs/heads where normal
 127   branches are stored.
 128
 129   This layout keeps your own branch namespace less cluttered,
 130   avoids name collision with your upstream, makes it possible
 131   to automatically track new branches created at the remote
 132   after you clone from it, and makes it easier to interact with
 133   more than one remote repository (you can use "git remote" to
 134   add other repositories to track).  There might be some
 135   surprises:
 136
 137   * 'git branch' does not show the remote tracking branches.
 138     It only lists your own branches.  Use '-r' option to view
 139     the tracking branches.
 140
 141   * If you are forking off of a branch obtained from the
 142     upstream, you would have done something like 'git branch
 143     my-next next', because traditional layout dropped the
 144     tracking branch 'next' into your own branch namespace.
 145     With the separate remote layout, you say 'git branch next
 146     origin/next', which allows you to use the matching name
 147     'next' for your own branch.  It also allows you to track a
 148     remote other than 'origin' (i.e. where you initially cloned
 149     from) and fork off of a branch from there the same way
 150     (e.g. "git branch mingw j6t/master").
 151
 152   Repositories initialized with the traditional layout continue
 153   to work.
 154
 155 - New branches that appear on the origin side after a clone is
 156   made are also tracked automatically.  This is done with an
 157   wildcard refspec "refs/heads/*:refs/remotes/origin/*", which
 158   older git does not understand, so if you clone with 1.5.0,
 159   you would need to downgrade remote.*.fetch in the
 160   configuration file to specify each branch you are interested
 161   in individually if you plan to fetch into the repository with
 162   older versions of git (but why would you?).
 163
 164 - Similarly, wildcard refspec "refs/heads/*:refs/remotes/me/*"
 165   can be given to "git-push" command to update the tracking
 166   branches that is used to track the repository you are pushing
 167   from on the remote side.
 168
 169 - git-branch and git-show-branch know remote tracking branches
 170   (use the command line switch "-r" to list only tracked branches).
 171
 172 - git-push can now be used to delete a remote branch or a tag.
 173   This requires the updated git on the remote side (use "git
 174   push <remote> :refs/heads/<branch>" to delete "branch").
 175
 176 - git-push more aggressively keeps the transferred objects
 177   packed.  Earlier we recommended to monitor amount of loose
 178   objects and repack regularly, but you should repack when you
 179   accumulated too many small packs this way as well.  Updated
 180   git-count-objects helps you with this.
 181
 182 - git-fetch also more aggressively keeps the transferred objects
 183   packed.  This behavior of git-push and git-fetch can be
 184   tweaked with a single configuration transfer.unpacklimit (but
 185   usually there should not be any need for a user to tweak it).
 186
 187 - A new command, git-remote, can help you manage your remote
 188   tracking branch definitions.
 189
 190 - You may need to specify explicit paths for upload-pack and/or
 191   receive-pack due to your ssh daemon configuration on the
 192   other end.  This can now be done via remote.*.uploadpack and
 193   remote.*.receivepack configuration.
 194
 195
 196* Bare repositories
 197
 198 - Certain commands change their behavior in a bare repository
 199   (i.e. a repository without associated working tree).  We use
 200   a fairly conservative heuristic (if $GIT_DIR is ".git", or
 201   ends with "/.git", the repository is not bare) to decide if a
 202   repository is bare, but "core.bare" configuration variable
 203   can be used to override the heuristic when it misidentifies
 204   your repository.
 205
 206 - git-fetch used to complain updating the current branch but
 207   this is now allowed for a bare repository.  So is the use of
 208   'git-branch -f' to update the current branch.
 209
 210 - Porcelain-ish commands that require a working tree refuses to
 211   work in a bare repository.
 212
 213
 214* Reflog
 215
 216 - Reflog records the history from the view point of the local
 217   repository. In other words, regardless of the real history,
 218   the reflog shows the history as seen by one particular
 219   repository (this enables you to ask "what was the current
 220   revision in _this_ repository, yesterday at 1pm?").  This
 221   facility is enabled by default for repositories with working
 222   trees, and can be accessed with the "branch@{time}" and
 223   "branch@{Nth}" notation.
 224
 225 - "git show-branch" learned showing the reflog data with the
 226   new -g option.  "git log" has -g option to view reflog
 227   entries in a more verbose manner.
 228
 229 - git-branch knows how to rename branches and moves existing
 230   reflog data from the old branch to the new one.
 231
 232 - In addition to the reflog support in v1.4.4 series, HEAD
 233   reference maintains its own log.  "HEAD@{5.minutes.ago}"
 234   means the commit you were at 5 minutes ago, which takes
 235   branch switching into account.  If you want to know where the
 236   tip of your current branch was at 5 minutes ago, you need to
 237   explicitly say its name (e.g. "master@{5.minutes.ago}") or
 238   omit the refname altogether i.e. "@{5.minutes.ago}".
 239
 240 - The commits referred to by reflog entries are now protected
 241   against pruning.  The new command "git reflog expire" can be
 242   used to truncate older reflog entries and entries that refer
 243   to commits that have been pruned away previously with older
 244   versions of git.
 245
 246   Existing repositories that have been using reflog may get
 247   complaints from fsck-objects and may not be able to run
 248   git-repack, if you had run git-prune from older git; please
 249   run "git reflog expire --stale-fix --all" first to remove
 250   reflog entries that refer to commits that are no longer in
 251   the repository when that happens.
 252
 253
 254* Crufts removal
 255
 256 - We used to say "old commits are retrievable using reflog and
 257   'master@{yesterday}' syntax as long as you haven't run
 258   git-prune".  We no longer have to say the latter half of the
 259   above sentence, as git-prune does not remove things reachable
 260   from reflog entries.
 261
 262 - There is a toplevel garbage collector script, 'git-gc', that
 263   runs periodic cleanup functions, including 'git-repack -a -d',
 264   'git-reflog expire', 'git-pack-refs --prune', and 'git-rerere
 265   gc'.
 266
 267 - The output from fsck ("fsck-objects" is called just "fsck"
 268   now, but the old name continues to work) was needlessly
 269   alarming in that it warned missing objects that are reachable
 270   only from dangling objects.  This has been corrected and the
 271   output is much more useful.
 272
 273
 274* Detached HEAD
 275
 276 - You can use 'git-checkout' to check out an arbitrary revision
 277   or a tag as well, instead of named branches.  This will
 278   dissociate your HEAD from the branch you are currently on.
 279
 280   A typical use of this feature is to "look around".  E.g.
 281
 282        $ git checkout v2.6.16
 283        ... compile, test, etc.
 284        $ git checkout v2.6.17
 285        ... compile, test, etc.
 286
 287 - After detaching your HEAD, you can go back to an existing
 288   branch with usual "git checkout $branch".  Also you can
 289   start a new branch using "git checkout -b $newbranch" to
 290   start a new branch at that commit.
 291
 292 - You can even pull from other repositories, make merges and
 293   commits while your HEAD is detached.  Also you can use "git
 294   reset" to jump to arbitrary commit, while still keeping your
 295   HEAD detached.
 296
 297   Remember that a detached state is volatile, i.e. it will be forgotten
 298   as soon as you move away from it with the checkout or reset command,
 299   unless a branch is created from it as mentioned above.  It is also
 300   possible to rescue a lost detached state from the HEAD reflog.
 301
 302
 303* Packed refs
 304
 305 - Repositories with hundreds of tags have been paying large
 306   overhead, both in storage and in runtime, due to the
 307   traditional one-ref-per-file format.  A new command,
 308   git-pack-refs, can be used to "pack" them in more efficient
 309   representation (you can let git-gc do this for you).
 310
 311 - Clones and fetches over dumb transports are now aware of
 312   packed refs and can download from repositories that use
 313   them.
 314
 315
 316* Configuration
 317
 318 - configuration related to color setting are consolidated under
 319   color.* namespace (older diff.color.*, status.color.* are
 320   still supported).
 321
 322 - 'git-repo-config' command is accessible as 'git-config' now.
 323
 324
 325* Updated features
 326
 327 - git-describe uses better criteria to pick a base ref.  It
 328   used to pick the one with the newest timestamp, but now it
 329   picks the one that is topologically the closest (that is,
 330   among ancestors of commit C, the ref T that has the shortest
 331   output from "git-rev-list T..C" is chosen).
 332
 333 - git-describe gives the number of commits since the base ref
 334   between the refname and the hash suffix.  E.g. the commit one
 335   before v2.6.20-rc6 in the kernel repository is:
 336
 337        v2.6.20-rc5-306-ga21b069
 338
 339   which tells you that its object name begins with a21b069,
 340   v2.6.20-rc5 is an ancestor of it (meaning, the commit
 341   contains everything -rc5 has), and there are 306 commits
 342   since v2.6.20-rc5.
 343
 344 - git-describe with --abbrev=0 can be used to show only the
 345   name of the base ref.
 346
 347 - git-blame learned a new option, --incremental, that tells it
 348   to output the blames as they are assigned.  A sample script
 349   to use it is also included as contrib/blameview.
 350
 351 - git-blame starts annotating from the working tree by default.
 352
 353
 354* Less external dependency
 355
 356 - We no longer require the "merge" program from the RCS suite.
 357   All 3-way file-level merges are now done internally.
 358
 359 - The original implementation of git-merge-recursive which was
 360   in Python has been removed; we have a C implementation of it
 361   now.
 362
 363 - git-shortlog is no longer a Perl script.  It no longer
 364   requires output piped from git-log; it can accept revision
 365   parameters directly on the command line.
 366
 367
 368* I18n
 369
 370 - We have always encouraged the commit message to be encoded in
 371   UTF-8, but the users are allowed to use legacy encoding as
 372   appropriate for their projects.  This will continue to be the
 373   case.  However, a non UTF-8 commit encoding _must_ be
 374   explicitly set with i18n.commitencoding in the repository
 375   where a commit is made; otherwise git-commit-tree will
 376   complain if the log message does not look like a valid UTF-8
 377   string.
 378
 379 - The value of i18n.commitencoding in the originating
 380   repository is recorded in the commit object on the "encoding"
 381   header, if it is not UTF-8.  git-log and friends notice this,
 382   and reencodes the message to the log output encoding when
 383   displaying, if they are different.  The log output encoding
 384   is determined by "git log --encoding=<encoding>",
 385   i18n.logoutputencoding configuration, or i18n.commitencoding
 386   configuration, in the decreasing order of preference, and
 387   defaults to UTF-8.
 388
 389 - Tools for e-mailed patch application now default to -u
 390   behavior; i.e. it always re-codes from the e-mailed encoding
 391   to the encoding specified with i18n.commitencoding.  This
 392   unfortunately forces projects that have happily been using a
 393   legacy encoding without setting i18n.commitencoding to set
 394   the configuration, but taken with other improvement, please
 395   excuse us for this very minor one-time inconvenience.
 396
 397
 398* e-mailed patches
 399
 400 - See the above I18n section.
 401
 402 - git-format-patch now enables --binary without being asked.
 403   git-am does _not_ default to it, as sending binary patch via
 404   e-mail is unusual and is harder to review than textual
 405   patches and it is prudent to require the person who is
 406   applying the patch to explicitly ask for it.
 407
 408 - The default suffix for git-format-patch output is now ".patch",
 409   not ".txt".  This can be changed with --suffix=.txt option,
 410   or setting the config variable "format.suffix" to ".txt".
 411
 412
 413* Foreign SCM interfaces
 414
 415 - git-svn now requires the Perl SVN:: libraries, the
 416   command-line backend was too slow and limited.
 417
 418 - the 'commit' subcommand of git-svn has been renamed to
 419   'set-tree', and 'dcommit' is the recommended replacement for
 420   day-to-day work.
 421
 422 - git fast-import backend.
 423
 424
 425* User support
 426
 427 - Quite a lot of documentation updates.
 428
 429 - Bash completion scripts have been updated heavily.
 430
 431 - Better error messages for often used Porcelainish commands.
 432
 433 - Git GUI.  This is a simple Tk based graphical interface for
 434   common Git operations.
 435
 436
 437* Sliding mmap
 438
 439 - We used to assume that we can mmap the whole packfile while
 440   in use, but with a large project this consumes huge virtual
 441   memory space and truly huge ones would not fit in the
 442   userland address space on 32-bit platforms.  We now mmap huge
 443   packfile in pieces to avoid this problem.
 444
 445
 446* Shallow clones
 447
 448 - There is a partial support for 'shallow' repositories that
 449   keeps only recent history.  A 'shallow clone' is created by
 450   specifying how deep that truncated history should be
 451   (e.g. "git clone --depth 5 git://some.where/repo.git").
 452
 453   Currently a shallow repository has number of limitations:
 454
 455   - Cloning and fetching _from_ a shallow clone are not
 456     supported (nor tested -- so they might work by accident but
 457     they are not expected to).
 458
 459   - Pushing from nor into a shallow clone are not expected to
 460     work.
 461
 462   - Merging inside a shallow repository would work as long as a
 463     merge base is found in the recent history, but otherwise it
 464     will be like merging unrelated histories and may result in
 465     huge conflicts.
 466
 467   but this would be more than adequate for people who want to
 468   look at near the tip of a big project with a deep history and
 469   send patches in e-mail format.