Git 2.5.0/2.4.7 发布，分布式版本控制系统

UI，工作流 & 新特性

* The bash completion script (in contrib/) learned a few options that

"git revert" takes.

* Whitespace breakages in deleted and context lines can also be

painted in the output of "git diff" and friends with the new

--ws-error-highlight option.

* List of commands shown by "git help" are grouped along the workflow

elements to help early learners.

* "git p4" now detects the filetype (e.g. binary) correctly even when

the files are opened exclusively.

* git p4 attempts to better handle branches in Perforce.

* "git p4" learned "--changes-block-size <n>" to read the changes in

chunks from Perforce, instead of making one call to "p4 changes"

that may trigger "too many rows scanned" error from Perforce.

* More workaround for Perforce's row number limit in "git p4".

* Unlike "$EDITOR" and "$GIT_EDITOR" that can hold the path to the

command and initial options (e.g. "/path/to/emacs -nw"), 'git p4'

did not let the shell interpolate the contents of the environment

variable that name the editor "$P4EDITOR" (and "$EDITOR", too).

* A new short-hand <branch>@{push} denotes the remote-tracking branch

that tracks the branch at the remote the <branch> would be pushed

to.

* "git show-branch --topics HEAD" (with no other arguments) did not

do anything interesting.  Instead, contrast the given revision

against all the local branches by default.

* A replacement for contrib/workdir/git-new-workdir that does not

rely on symbolic links and make sharing of objects and refs safer

by making the borrowee and borrowers aware of each other.

Consider this as still an experimental feature; its UI is still

likely to change.

* Tweak the sample "store" backend of the credential helper to honor

XDG configuration file locations when specified.

* A heuristic we use to catch mistyped paths on the command line

"git <cmd> <revs> <pathspec>" is to make sure that all the non-rev

parameters in the later part of the command line are names of the

files in the working tree, but that means "git grep $str -- /*.c"

must always be disambiguated with "--", because nobody sane will

create a file whose name literally is asterisk-dot-see. 

* "git merge FETCH_HEAD" learned that the previous "git fetch" could

be to create an Octopus merge, i.e. recording multiple branches

that are not marked as "not-for-merge"

* Filter scripts were run with SIGPIPE disabled on the Git side,

expecting that they may not read what Git feeds them to filter.

* Instead of dying immediately upon failing to obtain a lock, the

locking (of refs etc) retries after a short while with backoff.

* Introduce http.<url>.SSLCipherList configuration variable to tweak

the list of cipher suite to be used with libcURL when talking with

https:// sites.

* "git subtree" script (in contrib/) used "echo -n" to produce

progress messages in a non-portable way.

* "git subtree" script (in contrib/) does not have --squash option

when pushing, but the documentation and help text pretended as if

it did.

* The Git subcommand completion (in contrib/) no longer lists credential

helpers among candidates; they are not something the end user would

invoke interactively.

* The index file can be taught with "update-index --untracked-cache"

to optionally remember already seen untracked files, in order to

speed up "git status" in a working tree with tons of cruft.

* "git mergetool" learned to drive WinMerge as a backend.

* "git upload-pack" that serves "git fetch" can be told to serve

commits that are not at the tip of any ref, as long as they are

reachable from a ref, with uploadpack.allowReachableSHA1InWant

configuration variable.

* "git cat-file --batch(-check)" learned the "--follow-symlinks"

option that follows an in-tree symbolic link when asked about an

object via extended SHA-1 syntax

Consider this as still an experimental and incomplete feature:

- We may want to do the same for in-index objects, e.g.

asking for :RelNotes with this option should give

:Documentation/RelNotes/2.5.0.txt, too

- "git cat-file --follow-symlinks blob HEAD:RelNotes"

may also be something we want to allow in the future.

* "git send-email" learned the alias file format used by the sendmail

program (in a simplified form; we obviously do not feed pipes).

* Traditionally, external low-level 3-way merge drivers are expected

to produce their results based solely on the contents of the three

variants given in temporary files named by %O, %A and %B on their

command line.  Additionally allow them to look at the final path

(given by %P).

* "git blame" learned blame.showEmail configuration variable.

* "git apply" cannot diagnose a patch corruption when the breakage is

to mark the length of the hunk shorter than it really is on the

hunk header line "@@ -l,k +m,n @@"; one special case it could is

when the hunk becomes no-op (e.g. k == n == 2 for two-line context

patch output), and it learned to do so in this special case.

* Add the "--allow-unknown-type" option to "cat-file" to allow

inspecting loose objects of an experimental or a broken type.

* Many long-running operations show progress eye-candy, even when

they are later backgrounded.  Hide the eye-candy when the process

is sent to the background instead.

(merge a4fb76c lm/squelch-bg-progress later to maint).

性能，内部实现，开发支持等等：

* "unsigned char [20]" used throughout the code to represent object

names are being converted into a semi-opaque "struct object_id".

* for_each_ref() callback functions were taught to name the objects

not with "unsigned char sha1[20]" but with "struct object_id".

* Catch a programmer mistake to feed a pointer not an array to

ARRAY_SIZE() macro, by using a couple of GCC extensions.

* Some error messages in "git config" were emitted without calling

the usual error() facility.

* When "add--interactive" splits a hunk into two overlapping hunks

and then let the user choose only one, it sometimes feeds an

incorrect patch text to "git apply".  Add tests to demonstrate

this.

I have a slight suspicion that this may be $gmane/87202 coming back

and biting us (I seem to have said "let's run with this and see

what happens" back then).

* More line-ending tests.

* An earlier rewrite to use strbuf_getwholeline() instead of fgets(3)

to read packed-refs file revealed that the former is unacceptably

inefficient.  It has been optimized by using getdelim(3) when

available.

* The refs API uses ref_lock struct which had its own "int fd", even

though the same file descriptor was in the lock struct it contains.

Clean-up the code to lose this redundant field.

* There was a dead code that used to handle "git pull --tags" and

show special-cased error message, which was made irrelevant when

the semantics of the option changed back in Git 1.9 days.

(merge 19d122b pt/pull-tags-error-diag later to maint).

* Help us to find broken test script that splits the body part of the

test by mistaken use of wrong kind of quotes.

(merge d93d5d5 jc/test-prereq-validate later to maint).

* Developer support to automatically detect broken &&-chain in the

test scripts is now turned on by default.

(merge 92b269f jk/test-chain-lint later to maint).

* Error reporting mechanism used in "refs" API has been made more

consistent.

* "git pull" has more test coverage now.

* "git pull" has become more aware of the options meant for

underlying "git fetch" and then learned to use parse-options

parser.

* Clarify in the Makefile a guideline to decide use of USE_NSEC.

同时发布了 Git 2.4.7 版本，主要是 bug 修复， 更新内容 如下：

* A minor regression to "git fsck" in v2.2 era was fixed

* We used to ask libCURL to use the most secure authentication method

available when talking to an HTTP proxy only when we were told to

talk to one via configuration variables. 

* When you say "!<ENTER>" while running say "git log", you'd confuse

yourself in the resulting shell, that may look as if you took

control back to the original shell you spawned "git log" from but

that isn't what is happening. 

Stop leaking that environment variable to the pager's half of the

fork; we only need it on "Git" side when we spawn the pager.

* Avoid possible ssize_t to int truncation.

* "git config" failed to update the configuration file when the

underlying filesystem is incapable of renaming a file that is still

open.

* A minor bugfix when pack bitmap is used with "rev-list --count".

* An ancient test framework enhancement to allow color was not

entirely correct; this makes it work even when tput needs to read

from the ~/.terminfo under the user's real HOME directory.

* Fix a small bug in our use of umask() return value.

* "git rebase" did not exit with failure when format-patch it invoked

failed for whatever reason.

* Disable "have we lost a race with competing repack?" check while

receiving a huge object transfer that runs index-pack.