Documentation / RelNotes / 2.2.0.txton commit Merge branch 'rs/more-uses-of-skip-prefix' (145c590)
   1Git v2.2 Release Notes
   2======================
   3
   4Updates since v2.1
   5------------------
   6
   7Ports
   8
   9 * Building on older MacOS X systems automatically sets
  10   the necessary NO_APPLE_COMMON_CRYPTO build-time option.
  11
  12
  13UI, Workflows & Features
  14
  15 * "git archive" learned to filter what gets archived with pathspec.
  16
  17 * "git config --edit --global" starts from a skeletal per-user
  18   configuration file contents, instead of a total blank, when the
  19   user does not already have any.  This immediately reduces the
  20   need for a later "Have you forgotten setting core.user?" and we
  21   can add more to the template as we gain more experience.
  22
  23 * "git stash list -p" used to be almost always a no-op because each
  24   stash entry is represented as a merge commit.  It learned to show
  25   the difference between the base commit version and the working tree
  26   version, which is in line with what "git show" gives.
  27
  28 * Sometimes users want to report a bug they experience on their
  29   repository, but they are not at liberty to share the contents of
  30   the repository.  "fast-export" was taught an "--anonymize" option
  31   to replace blob contents, names of people and paths and log
  32   messages with bland and simple strings to help them.
  33
  34 * "log --date=iso" uses a slight variant of ISO 8601 format that is
  35   made more human readable.  A new "--date=iso-strict" option gives
  36   datetime output that is more strictly conformant.
  37
  38 * A broken reimplementation of Git could write an invalid index that
  39   records both stage #0 and higher stage entries for the same path.
  40   We now notice and reject such an index, as there is no sensible
  41   fallback (we do not know if the broken tool wanted to resolve and
  42   forgot to remove higher stage entries, or if it wanted to unresolve
  43   and forgot to remove the stage#0 entry).
  44
  45 * The "pre-receive" and "post-receive" hooks are no longer required
  46   to consume their input fully (not following this requirement used
  47   to result in intermittent errors in "git push").
  48
  49 * The pretty-format specifier "%d", which expanded to " (tagname)"
  50   for a tagged commit, gained a cousin "%D" that just gives the
  51   "tagname" without frills.
  52
  53 * "git push" learned "--signed" push, that allows a push (i.e.
  54   request to update the refs on the other side to point at a new
  55   history, together with the transmission of necessary objects) to be
  56   signed, so that it can be verified and audited, using the GPG
  57   signature of the person who pushed, that the tips of branches at a
  58   public repository really point the commits the pusher wanted to,
  59   without having to "trust" the server.
  60
  61Performance, Internal Implementation, etc.
  62
  63 * The API to manipulate the "refs" is currently undergoing a revamp
  64   to make it more transactional, with the eventual goal to allow
  65   all-or-none atomic updates and migrating the storage to something
  66   other than the traditional filesystem based one (e.g. databases).
  67
  68 * We no longer attempt to keep track of individual dependencies to
  69   the header files in the build procedure, relying on automated
  70   dependency generation support from modern compilers.
  71
  72 * In tests, we have been using NOT_{MINGW,CYGWIN} test prerequisites
  73   long before negated prerequisites e.g. !MINGW were invented.
  74   The former has been converted to the latter to avoid confusion.
  75
  76 * Looking up remotes configuration in a repository with very many
  77   remotes defined has been optimized.
  78
  79 * There are cases where you lock and open to write a file, close it
  80   to show the updated contents to external processes, and then have
  81   to update the file again while still holding the lock, but the
  82   lockfile API lacked support for such an access pattern.
  83
  84 * The API to allocate the structure to keep track of commit
  85   decoration has been updated to make it less cumbersome to use.
  86
  87 * An in-core caching layer to let us avoid reading the same
  88   configuration files number of times has been added.  A few commands
  89   have been converted to use this subsystem.
  90
  91 * Various code paths have been cleaned up and simplified by using
  92   "strbuf", "starts_with()", and "skip_prefix()" APIs more.
  93
  94 * A few codepaths that died when large blobs that would not fit in
  95   core are involved in their operation have been taught to punt
  96   instead, by e.g. marking too large a blob as not to be diffed.
  97
  98 * A few more code paths in "commit" and "checkout" have been taught
  99   to repopulate the cache-tree in the index, to help speed up later
 100   "write-tree" (used in "commit") and "diff-index --cached" (used in
 101   "status").
 102
 103 * A common programming mistake to assign the same short option name
 104   to two separate options is detected by parse_options() API to help
 105   developers.
 106
 107 * The code path to write out the packed-refs file has been optimized,
 108   which especially matters in a repository with a large number of
 109   refs.
 110
 111 * The check to see if a ref $F can be created by making sure no
 112   existing ref has $F/ as its prefix has been optimized, which
 113   especially matters in a repository with a large number of existing
 114   refs.
 115
 116 * "git fsck" was taught to check contents of tag objects a bit more.
 117
 118 * "git hash-object" was taught a "--literally" option to help
 119   debugging.
 120
 121 * When running a required clean filter, we do not have to mmap the
 122   original before feeding the filter.  Instead, stream the file
 123   contents directly to the filter and process its output.
 124
 125Also contains various documentation updates and code clean-ups.
 126
 127
 128Fixes since v2.1
 129----------------
 130
 131Unless otherwise noted, all the fixes since v2.1 in the maintenance
 132track are contained in this release (see the maintenance releases'
 133notes for details).
 134
 135 * "git log --pretty/format=" with an empty format string did not
 136   mean the more obvious "No output whatsoever" but "Use default
 137   format", which was counterintuitive.
 138
 139 * Implementations of "tar" that do not understand an extended pax
 140   header would extract the contents of it in a regular file; make
 141   sure the permission bits of this file follows the same tar.umask
 142   configuration setting.
 143
 144 * "git -c section.var command" and "git -c section.var= command"
 145   should pass the configuration differently (the former should be a
 146   boolean true, the latter should be an empty string).
 147
 148 * Applying a patch not generated by Git in a subdirectory used to
 149   check the whitespace breakage using the attributes for incorrect
 150   paths. Also whitespace checks were performed even for paths
 151   excluded via "git apply --exclude=<path>" mechanism.
 152
 153 * "git bundle create" with date-range specification were meant to
 154   exclude tags outside the range, but it didn't.
 155
 156 * "git add x" where x that used to be a directory has become a
 157   symbolic link to a directory misbehaved.
 158
 159 * The prompt script checked $GIT_DIR/ref/stash file to see if there
 160   is a stash, which was a no-no.
 161
 162 * Pack-protocol documentation had a minor typo.
 163
 164 * "git checkout -m" did not switch to another branch while carrying
 165   the local changes forward when a path was deleted from the index.
 166
 167 * With sufficiently long refnames, "git fast-import" could have
 168   overflown an on-stack buffer.
 169
 170 * After "pack-refs --prune" packed refs at the top-level, it failed
 171   to prune them.
 172
 173 * Progress output from "git gc --auto" was visible in "git fetch -q".
 174
 175 * We used to pass -1000 to poll(2), expecting it to also mean "no
 176   timeout", which should be spelled as -1.
 177
 178 * "git rebase" documentation was unclear that it is required to
 179   specify on what <upstream> the rebase is to be done when telling it
 180   to first check out <branch>.
 181   (merge 95c6826 so/rebase-doc later to maint).
 182
 183 * "git push" over HTTP transport had an artificial limit on number of
 184   refs that can be pushed imposed by the command line length.
 185   (merge 26be19b jk/send-pack-many-refspecs later to maint).
 186
 187 * When receiving an invalid pack stream that records the same object
 188   twice, multiple threads got confused due to a race.
 189   (merge ab791dd jk/index-pack-threading-races later to maint).
 190
 191 * An attempt to remove the entire tree in the "git fast-import" input
 192   stream caused it to misbehave.
 193   (merge 2668d69 mb/fast-import-delete-root later to maint).
 194
 195 * Reachability check (used in "git prune" and friends) did not add a
 196   detached HEAD as a starting point to traverse objects still in use.
 197   (merge c40fdd0 mk/reachable-protect-detached-head later to maint).
 198
 199 * "git config --add section.var val" used to lose existing
 200   section.var whose value was an empty string.
 201   (merge c1063be ta/config-add-to-empty-or-true-fix later to maint).
 202
 203 * "git fsck" failed to report that it found corrupt objects via its
 204   exit status in some cases.
 205   (merge 30d1038 jk/fsck-exit-code-fix later to maint).
 206
 207 * Use of "--verbose" option used to break "git branch --merged".
 208   (merge 12994dd jk/maint-branch-verbose-merged later to maint).
 209
 210 * Some MUAs mangled a line in a message that begins with "From " to
 211   ">From " when writing to a mailbox file and feeding such an input
 212   to "git am" used to lose such a line.
 213   (merge 85de86a jk/mbox-from-line later to maint).
 214
 215 * "rev-parse --verify --quiet $name" is meant to quietly exit with a
 216   non-zero status when $name is not a valid object name, but still
 217   gave error messages in some cases.