mirror of
https://github.com/git/git.git
synced 2026-08-09 01:21:47 +00:00
Merge branch 'master' into sp/reflog
* master: (90 commits) fetch.c: remove an unused variable and dead code. Clean up sha1 file writing Builtin git-cat-file builtin format-patch: squelch content-type for 7-bit ASCII CMIT_FMT_EMAIL: Q-encode Subject: and display-name part of From: fields. add more informative error messages to git-mktag remove the artificial restriction tagsize < 8kb git-rebase: use canonical A..B syntax to format-patch git-format-patch: now built-in. fmt-patch: Support --attach fmt-patch: understand old <his> notation Teach fmt-patch about --keep-subject Teach fmt-patch about --numbered fmt-patch: implement -o <dir> fmt-patch: output file names to stdout Teach fmt-patch to write individual files. built-in tar-tree and remote tar-tree Builtin git-diff-files, git-diff-index, git-diff-stages, and git-diff-tree. Builtin git-show-branch. Builtin git-apply. ...
This commit is contained in:
Junio C Hamano
@@ -7,6 +7,7 @@ MAN7_TXT=git.txt
|
||||
DOC_HTML=$(patsubst %.txt,%.html,$(MAN1_TXT) $(MAN7_TXT))
|
||||
|
||||
ARTICLES = tutorial
|
||||
ARTICLES += tutorial-2
|
||||
ARTICLES += core-tutorial
|
||||
ARTICLES += cvs-migration
|
||||
ARTICLES += diffcore
|
||||
|
||||
@@ -266,8 +266,8 @@ This recipe appears to work with the current [*1*] Thunderbird from Suse.
|
||||
The following Thunderbird extensions are needed:
|
||||
AboutConfig 0.5
|
||||
http://aboutconfig.mozdev.org/
|
||||
External Editor 0.5.4
|
||||
http://extensionroom.mozdev.org/more-info/exteditor
|
||||
External Editor 0.7.2
|
||||
http://globs.org/articles.php?lng=en&pg=8
|
||||
|
||||
1) Prepare the patch as a text file using your method of choice.
|
||||
|
||||
|
||||
@@ -14,11 +14,13 @@ DESCRIPTION
|
||||
A simple wrapper for git-update-index to add files to the index,
|
||||
for people used to do "cvs add".
|
||||
|
||||
It only adds non-ignored files, to add ignored files use
|
||||
"git update-index --add".
|
||||
|
||||
OPTIONS
|
||||
-------
|
||||
<file>...::
|
||||
Files to add to the index.
|
||||
Files to add to the index (see gitlink:git-ls-files[1]).
|
||||
|
||||
-n::
|
||||
Don't actually add the file(s), just show if they exist.
|
||||
@@ -68,6 +70,7 @@ git-add git-*.sh::
|
||||
See Also
|
||||
--------
|
||||
gitlink:git-rm[1]
|
||||
gitlink:git-ls-files[1]
|
||||
|
||||
Author
|
||||
------
|
||||
|
||||
@@ -49,6 +49,9 @@ OPTIONS
|
||||
|
||||
<branchname>::
|
||||
The name of the branch to create or delete.
|
||||
The new branch name must pass all checks defined by
|
||||
gitlink:git-check-ref-format[1]. Some of these checks
|
||||
may restrict the characters allowed in a branch name.
|
||||
|
||||
<start-point>::
|
||||
The new branch will be created with a HEAD equal to this. It may
|
||||
|
||||
@@ -45,6 +45,8 @@ refname expressions (see gitlink:git-rev-parse[1]). Namely:
|
||||
|
||||
. colon `:` is used as in `srcref:dstref` to mean "use srcref\'s
|
||||
value and store it in dstref" in fetch and push operations.
|
||||
It may also be used to select a specific object such as with
|
||||
gitlink:git-cat-file[1] "git-cat-file blob v1.3.3:refs.c".
|
||||
|
||||
|
||||
GIT
|
||||
|
||||
@@ -35,7 +35,10 @@ OPTIONS
|
||||
Force a re-read of everything.
|
||||
|
||||
-b::
|
||||
Create a new branch and start it at <branch>.
|
||||
Create a new branch named <new_branch> and start it at
|
||||
<branch>. The new branch name must pass all checks defined
|
||||
by gitlink:git-check-ref-format[1]. Some of these checks
|
||||
may restrict the characters allowed in a branch name.
|
||||
|
||||
-l::
|
||||
Create the new branch's ref log. This activates recording of
|
||||
|
||||
61
Documentation/git-quiltimport.txt
Normal file
61
Documentation/git-quiltimport.txt
Normal file
@@ -0,0 +1,61 @@
|
||||
git-quiltimport(1)
|
||||
================
|
||||
|
||||
NAME
|
||||
----
|
||||
git-quiltimport - Applies a quilt patchset onto the current branch
|
||||
|
||||
|
||||
SYNOPSIS
|
||||
--------
|
||||
[verse]
|
||||
'git-quiltimport' [--dry-run] [--author <author>] [--patches <dir>]
|
||||
|
||||
|
||||
DESCRIPTION
|
||||
-----------
|
||||
Applies a quilt patchset onto the current git branch, preserving
|
||||
the patch boundaries, patch order, and patch descriptions present
|
||||
in the quilt patchset.
|
||||
|
||||
For each patch the code attempts to extract the author from the
|
||||
patch description. If that fails it falls back to the author
|
||||
specified with --author. If the --author flag was not given
|
||||
the patch description is displayed and the user is asked to
|
||||
interactively enter the author of the patch.
|
||||
|
||||
If a subject is not found in the patch description the patch name is
|
||||
preserved as the 1 line subject in the git description.
|
||||
|
||||
OPTIONS
|
||||
-------
|
||||
--dry-run::
|
||||
Walk through the patches in the series and warn
|
||||
if we cannot find all of the necessary information to commit
|
||||
a patch. At the time of this writing only missing author
|
||||
information is warned about.
|
||||
|
||||
--author Author Name <Author Email>::
|
||||
The author name and email address to use when no author
|
||||
information can be found in the patch description.
|
||||
|
||||
--patches <dir>::
|
||||
The directory to find the quilt patches and the
|
||||
quilt series file.
|
||||
|
||||
The default for the patch directory is patches
|
||||
or the value of the $QUILT_PATCHES environment
|
||||
variable.
|
||||
|
||||
Author
|
||||
------
|
||||
Written by Eric Biederman <ebiederm@lnxi.com>
|
||||
|
||||
Documentation
|
||||
--------------
|
||||
Documentation by Eric Biederman <ebiederm@lnxi.com>
|
||||
|
||||
GIT
|
||||
---
|
||||
Part of the gitlink:git[7] suite
|
||||
|
||||
@@ -4,12 +4,16 @@ T="$1"
|
||||
|
||||
for h in *.html *.txt howto/*.txt howto/*.html
|
||||
do
|
||||
diff -u -I'Last updated [0-9][0-9]-[A-Z][a-z][a-z]-' "$T/$h" "$h" || {
|
||||
if test -f "$T/$h" &&
|
||||
diff -u -I'Last updated [0-9][0-9]-[A-Z][a-z][a-z]-' "$T/$h" "$h"
|
||||
then
|
||||
:; # up to date
|
||||
else
|
||||
echo >&2 "# install $h $T/$h"
|
||||
rm -f "$T/$h"
|
||||
mkdir -p `dirname "$T/$h"`
|
||||
cp "$h" "$T/$h"
|
||||
}
|
||||
fi
|
||||
done
|
||||
strip_leading=`echo "$T/" | sed -e 's|.|.|g'`
|
||||
for th in "$T"/*.html "$T"/*.txt "$T"/howto/*.txt "$T"/howto/*.html
|
||||
|
||||
391
Documentation/tutorial-2.txt
Normal file
391
Documentation/tutorial-2.txt
Normal file
@@ -0,0 +1,391 @@
|
||||
A tutorial introduction to git: part two
|
||||
========================================
|
||||
|
||||
You should work through link:tutorial.html[A tutorial introduction to
|
||||
git] before reading this tutorial.
|
||||
|
||||
The goal of this tutorial is to introduce two fundamental pieces of
|
||||
git's architecture--the object database and the index file--and to
|
||||
provide the reader with everything necessary to understand the rest
|
||||
of the git documentation.
|
||||
|
||||
The git object database
|
||||
-----------------------
|
||||
|
||||
Let's start a new project and create a small amount of history:
|
||||
|
||||
------------------------------------------------
|
||||
$ mkdir test-project
|
||||
$ cd test-project
|
||||
$ git init-db
|
||||
defaulting to local storage area
|
||||
$ echo 'hello world' > file.txt
|
||||
$ git add .
|
||||
$ git commit -a -m "initial commit"
|
||||
Committing initial tree 92b8b694ffb1675e5975148e1121810081dbdffe
|
||||
$ echo 'hello world!' >file.txt
|
||||
$ git commit -a -m "add emphasis"
|
||||
------------------------------------------------
|
||||
|
||||
What are the 40 digits of hex that git responded to the first commit
|
||||
with?
|
||||
|
||||
We saw in part one of the tutorial that commits have names like this.
|
||||
It turns out that every object in the git history is stored under
|
||||
such a 40-digit hex name. That name is the SHA1 hash of the object's
|
||||
contents; among other things, this ensures that git will never store
|
||||
the same data twice (since identical data is given an identical SHA1
|
||||
name), and that the contents of a git object will never change (since
|
||||
that would change the object's name as well).
|
||||
|
||||
We can ask git about this particular object with the cat-file
|
||||
command--just cut-and-paste from the reply to the initial commit, to
|
||||
save yourself typing all 40 hex digits:
|
||||
|
||||
------------------------------------------------
|
||||
$ git cat-file -t 92b8b694ffb1675e5975148e1121810081dbdffe
|
||||
tree
|
||||
------------------------------------------------
|
||||
|
||||
A tree can refer to one or more "blob" objects, each corresponding to
|
||||
a file. In addition, a tree can also refer to other tree objects,
|
||||
thus creating a directory heirarchy. You can examine the contents of
|
||||
any tree using ls-tree (remember that a long enough initial portion
|
||||
of the SHA1 will also work):
|
||||
|
||||
------------------------------------------------
|
||||
$ git ls-tree 92b8b694
|
||||
100644 blob 3b18e512dba79e4c8300dd08aeb37f8e728b8dad file.txt
|
||||
------------------------------------------------
|
||||
|
||||
Thus we see that this tree has one file in it. The SHA1 hash is a
|
||||
reference to that file's data:
|
||||
|
||||
------------------------------------------------
|
||||
$ git cat-file -t 3b18e512
|
||||
blob
|
||||
------------------------------------------------
|
||||
|
||||
A "blob" is just file data, which we can also examine with cat-file:
|
||||
|
||||
------------------------------------------------
|
||||
$ git cat-file blob 3b18e512
|
||||
hello world
|
||||
------------------------------------------------
|
||||
|
||||
Note that this is the old file data; so the object that git named in
|
||||
its response to the initial tree was a tree with a snapshot of the
|
||||
directory state that was recorded by the first commit.
|
||||
|
||||
All of these objects are stored under their SHA1 names inside the git
|
||||
directory:
|
||||
|
||||
------------------------------------------------
|
||||
$ find .git/objects/
|
||||
.git/objects/
|
||||
.git/objects/pack
|
||||
.git/objects/info
|
||||
.git/objects/3b
|
||||
.git/objects/3b/18e512dba79e4c8300dd08aeb37f8e728b8dad
|
||||
.git/objects/92
|
||||
.git/objects/92/b8b694ffb1675e5975148e1121810081dbdffe
|
||||
.git/objects/54
|
||||
.git/objects/54/196cc2703dc165cbd373a65a4dcf22d50ae7f7
|
||||
.git/objects/a0
|
||||
.git/objects/a0/423896973644771497bdc03eb99d5281615b51
|
||||
.git/objects/d0
|
||||
.git/objects/d0/492b368b66bdabf2ac1fd8c92b39d3db916e59
|
||||
.git/objects/c4
|
||||
.git/objects/c4/d59f390b9cfd4318117afde11d601c1085f241
|
||||
------------------------------------------------
|
||||
|
||||
and the contents of these files is just the compressed data plus a
|
||||
header identifying their length and their type. The type is either a
|
||||
blob, a tree, a commit, or a tag. We've seen a blob and a tree now,
|
||||
so next we should look at a commit.
|
||||
|
||||
The simplest commit to find is the HEAD commit, which we can find
|
||||
from .git/HEAD:
|
||||
|
||||
------------------------------------------------
|
||||
$ cat .git/HEAD
|
||||
ref: refs/heads/master
|
||||
------------------------------------------------
|
||||
|
||||
As you can see, this tells us which branch we're currently on, and it
|
||||
tells us this by naming a file under the .git directory, which itself
|
||||
contains a SHA1 name referring to a commit object, which we can
|
||||
examine with cat-file:
|
||||
|
||||
------------------------------------------------
|
||||
$ cat .git/refs/heads/master
|
||||
c4d59f390b9cfd4318117afde11d601c1085f241
|
||||
$ git cat-file -t c4d59f39
|
||||
commit
|
||||
$ git cat-file commit c4d59f39
|
||||
tree d0492b368b66bdabf2ac1fd8c92b39d3db916e59
|
||||
parent 54196cc2703dc165cbd373a65a4dcf22d50ae7f7
|
||||
author J. Bruce Fields <bfields@puzzle.fieldses.org> 1143418702 -0500
|
||||
committer J. Bruce Fields <bfields@puzzle.fieldses.org> 1143418702 -0500
|
||||
|
||||
add emphasis
|
||||
------------------------------------------------
|
||||
|
||||
The "tree" object here refers to the new state of the tree:
|
||||
|
||||
------------------------------------------------
|
||||
$ git ls-tree d0492b36
|
||||
100644 blob a0423896973644771497bdc03eb99d5281615b51 file.txt
|
||||
$ git cat-file commit a0423896
|
||||
hello world!
|
||||
------------------------------------------------
|
||||
|
||||
and the "parent" object refers to the previous commit:
|
||||
|
||||
------------------------------------------------
|
||||
$ git-cat-file commit 54196cc2
|
||||
tree 92b8b694ffb1675e5975148e1121810081dbdffe
|
||||
author J. Bruce Fields <bfields@puzzle.fieldses.org> 1143414668 -0500
|
||||
committer J. Bruce Fields <bfields@puzzle.fieldses.org> 1143414668 -0500
|
||||
|
||||
initial commit
|
||||
------------------------------------------------
|
||||
|
||||
The tree object is the tree we examined first, and this commit is
|
||||
unusual in that it lacks any parent.
|
||||
|
||||
Most commits have only one parent, but it is also common for a commit
|
||||
to have multiple parents. In that case the commit represents a
|
||||
merge, with the parent references pointing to the heads of the merged
|
||||
branches.
|
||||
|
||||
Besides blobs, trees, and commits, the only remaining type of object
|
||||
is a "tag", which we won't discuss here; refer to gitlink:git-tag[1]
|
||||
for details.
|
||||
|
||||
So now we know how git uses the object database to represent a
|
||||
project's history:
|
||||
|
||||
* "commit" objects refer to "tree" objects representing the
|
||||
snapshot of a directory tree at a particular point in the
|
||||
history, and refer to "parent" commits to show how they're
|
||||
connected into the project history.
|
||||
* "tree" objects represent the state of a single directory,
|
||||
associating directory names to "blob" objects containing file
|
||||
data and "tree" objects containing subdirectory information.
|
||||
* "blob" objects contain file data without any other structure.
|
||||
* References to commit objects at the head of each branch are
|
||||
stored in files under .git/refs/heads/.
|
||||
* The name of the current branch is stored in .git/HEAD.
|
||||
|
||||
Note, by the way, that lots of commands take a tree as an argument.
|
||||
But as we can see above, a tree can be referred to in many different
|
||||
ways--by the SHA1 name for that tree, by the name of a commit that
|
||||
refers to the tree, by the name of a branch whose head refers to that
|
||||
tree, etc.--and most such commands can accept any of these names.
|
||||
|
||||
In command synopses, the word "tree-ish" is sometimes used to
|
||||
designate such an argument.
|
||||
|
||||
The index file
|
||||
--------------
|
||||
|
||||
The primary tool we've been using to create commits is "git commit
|
||||
-a", which creates a commit including every change you've made to
|
||||
your working tree. But what if you want to commit changes only to
|
||||
certain files? Or only certain changes to certain files?
|
||||
|
||||
If we look at the way commits are created under the cover, we'll see
|
||||
that there are more flexible ways creating commits.
|
||||
|
||||
Continuing with our test-project, let's modify file.txt again:
|
||||
|
||||
------------------------------------------------
|
||||
$ echo "hello world, again" >>file.txt
|
||||
------------------------------------------------
|
||||
|
||||
but this time instead of immediately making the commit, let's take an
|
||||
intermediate step, and ask for diffs along the way to keep track of
|
||||
what's happening:
|
||||
|
||||
------------------------------------------------
|
||||
$ git diff
|
||||
--- a/file.txt
|
||||
+++ b/file.txt
|
||||
@@ -1 +1,2 @@
|
||||
hello world!
|
||||
+hello world, again
|
||||
$ git update-index file.txt
|
||||
$ git diff
|
||||
------------------------------------------------
|
||||
|
||||
The last diff is empty, but no new commits have been made, and the
|
||||
head still doesn't contain the new line:
|
||||
|
||||
------------------------------------------------
|
||||
$ git-diff HEAD
|
||||
diff --git a/file.txt b/file.txt
|
||||
index a042389..513feba 100644
|
||||
--- a/file.txt
|
||||
+++ b/file.txt
|
||||
@@ -1 +1,2 @@
|
||||
hello world!
|
||||
+hello world, again
|
||||
------------------------------------------------
|
||||
|
||||
So "git diff" is comparing against something other than the head.
|
||||
The thing that it's comparing against is actually the index file,
|
||||
which is stored in .git/index in a binary format, but whose contents
|
||||
we can examine with ls-files:
|
||||
|
||||
------------------------------------------------
|
||||
$ git ls-files --stage
|
||||
100644 513feba2e53ebbd2532419ded848ba19de88ba00 0 file.txt
|
||||
$ git cat-file -t 513feba2
|
||||
blob
|
||||
$ git cat-file blob 513feba2
|
||||
hello world, again
|
||||
------------------------------------------------
|
||||
|
||||
So what our "git update-index" did was store a new blob and then put
|
||||
a reference to it in the index file. If we modify the file again,
|
||||
we'll see that the new modifications are reflected in the "git-diff"
|
||||
output:
|
||||
|
||||
------------------------------------------------
|
||||
$ echo 'again?' >>file.txt
|
||||
$ git diff
|
||||
index 513feba..ba3da7b 100644
|
||||
--- a/file.txt
|
||||
+++ b/file.txt
|
||||
@@ -1,2 +1,3 @@
|
||||
hello world!
|
||||
hello world, again
|
||||
+again?
|
||||
------------------------------------------------
|
||||
|
||||
With the right arguments, git diff can also show us the difference
|
||||
between the working directory and the last commit, or between the
|
||||
index and the last commit:
|
||||
|
||||
------------------------------------------------
|
||||
$ git diff HEAD
|
||||
diff --git a/file.txt b/file.txt
|
||||
index a042389..ba3da7b 100644
|
||||
--- a/file.txt
|
||||
+++ b/file.txt
|
||||
@@ -1 +1,3 @@
|
||||
hello world!
|
||||
+hello world, again
|
||||
+again?
|
||||
$ git diff --cached
|
||||
diff --git a/file.txt b/file.txt
|
||||
index a042389..513feba 100644
|
||||
--- a/file.txt
|
||||
+++ b/file.txt
|
||||
@@ -1 +1,2 @@
|
||||
hello world!
|
||||
+hello world, again
|
||||
------------------------------------------------
|
||||
|
||||
At any time, we can create a new commit using "git commit" (without
|
||||
the -a option), and verify that the state committed only includes the
|
||||
changes stored in the index file, not the additional change that is
|
||||
still only in our working tree:
|
||||
|
||||
------------------------------------------------
|
||||
$ git commit -m "repeat"
|
||||
$ git diff HEAD
|
||||
diff --git a/file.txt b/file.txt
|
||||
index 513feba..ba3da7b 100644
|
||||
--- a/file.txt
|
||||
+++ b/file.txt
|
||||
@@ -1,2 +1,3 @@
|
||||
hello world!
|
||||
hello world, again
|
||||
+again?
|
||||
------------------------------------------------
|
||||
|
||||
So by default "git commit" uses the index to create the commit, not
|
||||
the working tree; the -a option to commit tells it to first update
|
||||
the index with all changes in the working tree.
|
||||
|
||||
Finally, it's worth looking at the effect of "git add" on the index
|
||||
file:
|
||||
|
||||
------------------------------------------------
|
||||
$ echo "goodbye, world" >closing.txt
|
||||
$ git add closing.txt
|
||||
------------------------------------------------
|
||||
|
||||
The effect of the "git add" was to add one entry to the index file:
|
||||
|
||||
------------------------------------------------
|
||||
$ git ls-files --stage
|
||||
100644 8b9743b20d4b15be3955fc8d5cd2b09cd2336138 0 closing.txt
|
||||
100644 513feba2e53ebbd2532419ded848ba19de88ba00 0 file.txt
|
||||
------------------------------------------------
|
||||
|
||||
And, as you can see with cat-file, this new entry refers to the
|
||||
current contents of the file:
|
||||
|
||||
------------------------------------------------
|
||||
$ git cat-file blob a6b11f7a
|
||||
goodbye, word
|
||||
------------------------------------------------
|
||||
|
||||
The "status" command is a useful way to get a quick summary of the
|
||||
situation:
|
||||
|
||||
------------------------------------------------
|
||||
$ git status
|
||||
#
|
||||
# Updated but not checked in:
|
||||
# (will commit)
|
||||
#
|
||||
# new file: closing.txt
|
||||
#
|
||||
#
|
||||
# Changed but not updated:
|
||||
# (use git-update-index to mark for commit)
|
||||
#
|
||||
# modified: file.txt
|
||||
#
|
||||
------------------------------------------------
|
||||
|
||||
Since the current state of closing.txt is cached in the index file,
|
||||
it is listed as "updated but not checked in". Since file.txt has
|
||||
changes in the working directory that aren't reflected in the index,
|
||||
it is marked "changed but not updated". At this point, running "git
|
||||
commit" would create a commit that added closing.txt (with its new
|
||||
contents), but that didn't modify file.txt.
|
||||
|
||||
Also, note that a bare "git diff" shows the changes to file.txt, but
|
||||
not the addition of closing.txt, because the version of closing.txt
|
||||
in the index file is identical to the one in the working directory.
|
||||
|
||||
In addition to being the staging area for new commits, the index file
|
||||
is also populated from the object database when checking out a
|
||||
branch, and is used to hold the trees involved in a merge operation.
|
||||
See the link:core-tutorial.txt[core tutorial] and the relevant man
|
||||
pages for details.
|
||||
|
||||
What next?
|
||||
----------
|
||||
|
||||
At this point you should know everything necessary to read the man
|
||||
pages for any of the git commands; one good place to start would be
|
||||
with the commands mentioned in link:everyday.html[Everyday git]. You
|
||||
should be able to find any unknown jargon in the
|
||||
link:glossary.html[Glosssay].
|
||||
|
||||
The link:cvs-migration.html[CVS migration] document explains how to
|
||||
import a CVS repository into git, and shows how to use git in a
|
||||
CVS-like way.
|
||||
|
||||
For some interesting examples of git use, see the
|
||||
link:howto-index.html[howtos].
|
||||
|
||||
For git developers, the link:core-tutorial.html[Core tutorial] goes
|
||||
into detail on the lower-level git mechanisms involved in, for
|
||||
example, creating a new commit.
|
||||
@@ -80,13 +80,13 @@ file; just remove it, then commit.
|
||||
At any point you can view the history of your changes using
|
||||
|
||||
------------------------------------------------
|
||||
$ git whatchanged
|
||||
$ git log
|
||||
------------------------------------------------
|
||||
|
||||
If you also want to see complete diffs at each step, use
|
||||
|
||||
------------------------------------------------
|
||||
$ git whatchanged -p
|
||||
$ git log -p
|
||||
------------------------------------------------
|
||||
|
||||
Managing branches
|
||||
@@ -216,7 +216,7 @@ This actually pulls changes from the branch in Bob's repository named
|
||||
"master". Alice could request a different branch by adding the name
|
||||
of the branch to the end of the git pull command line.
|
||||
|
||||
This merges Bob's changes into her repository; "git whatchanged" will
|
||||
This merges Bob's changes into her repository; "git log" will
|
||||
now show the new commits. If Alice has made her own changes in the
|
||||
meantime, then Bob's changes will be merged in, and she will need to
|
||||
manually fix any conflicts.
|
||||
@@ -234,7 +234,7 @@ named bob-incoming. (Unlike git pull, git fetch just fetches a copy
|
||||
of Bob's line of development without doing any merging). Then
|
||||
|
||||
-------------------------------------
|
||||
$ git whatchanged -p master..bob-incoming
|
||||
$ git log -p master..bob-incoming
|
||||
-------------------------------------
|
||||
|
||||
shows a list of all the changes that Bob made since he branched from
|
||||
@@ -288,102 +288,179 @@ Git can also be used in a CVS-like mode, with a central repository
|
||||
that various users push changes to; see gitlink:git-push[1] and
|
||||
link:cvs-migration.html[git for CVS users].
|
||||
|
||||
Keeping track of history
|
||||
------------------------
|
||||
Exploring history
|
||||
-----------------
|
||||
|
||||
Git history is represented as a series of interrelated commits. The
|
||||
most recent commit in the currently checked-out branch can always be
|
||||
referred to as HEAD, and the "parent" of any commit can always be
|
||||
referred to by appending a caret, "^", to the end of the name of the
|
||||
commit. So, for example,
|
||||
Git history is represented as a series of interrelated commits. We
|
||||
have already seen that the git log command can list those commits.
|
||||
Note that first line of each git log entry also gives a name for the
|
||||
commit:
|
||||
|
||||
-------------------------------------
|
||||
git diff HEAD^ HEAD
|
||||
$ git log
|
||||
commit c82a22c39cbc32576f64f5c6b3f24b99ea8149c7
|
||||
Author: Junio C Hamano <junkio@cox.net>
|
||||
Date: Tue May 16 17:18:22 2006 -0700
|
||||
|
||||
merge-base: Clarify the comments on post processing.
|
||||
-------------------------------------
|
||||
|
||||
shows the difference between the most-recently checked-in state of
|
||||
the tree and the previous state, and
|
||||
We can give this name to git show to see the details about this
|
||||
commit.
|
||||
|
||||
-------------------------------------
|
||||
git diff HEAD^^ HEAD^
|
||||
$ git show c82a22c39cbc32576f64f5c6b3f24b99ea8149c7
|
||||
-------------------------------------
|
||||
|
||||
shows the difference between that previous state and the state two
|
||||
commits ago. Also, HEAD~5 can be used as a shorthand for HEAD{caret}{caret}{caret}{caret}{caret},
|
||||
and more generally HEAD~n can refer to the nth previous commit.
|
||||
Commits representing merges have more than one parent, and you can
|
||||
specify which parent to follow in that case; see
|
||||
gitlink:git-rev-parse[1].
|
||||
|
||||
The name of a branch can also be used to refer to the most recent
|
||||
commit on that branch; so you can also say things like
|
||||
But there other ways to refer to commits. You can use any initial
|
||||
part of the name that is long enough to uniquely identify the commit:
|
||||
|
||||
-------------------------------------
|
||||
git diff HEAD experimental
|
||||
$ git show c82a22c39c # the first few characters of the name are
|
||||
# usually enough
|
||||
$ git show HEAD # the tip of the current branch
|
||||
$ git show experimental # the tip of the "experimental" branch
|
||||
-------------------------------------
|
||||
|
||||
to see the difference between the most-recently committed tree in
|
||||
the current branch and the most-recently committed tree in the
|
||||
experimental branch.
|
||||
|
||||
But you may find it more useful to see the list of commits made in
|
||||
the experimental branch but not in the current branch, and
|
||||
Every commit has at least one "parent" commit, which points to the
|
||||
previous state of the project:
|
||||
|
||||
-------------------------------------
|
||||
git whatchanged HEAD..experimental
|
||||
$ git show HEAD^ # to see the parent of HEAD
|
||||
$ git show HEAD^^ # to see the grandparent of HEAD
|
||||
$ git show HEAD~4 # to see the great-great grandparent of HEAD
|
||||
-------------------------------------
|
||||
|
||||
will do that, just as
|
||||
Note that merge commits may have more than one parent:
|
||||
|
||||
-------------------------------------
|
||||
git whatchanged experimental..HEAD
|
||||
$ git show HEAD^1 # show the first parent of HEAD (same as HEAD^)
|
||||
$ git show HEAD^2 # show the second parent of HEAD
|
||||
-------------------------------------
|
||||
|
||||
will show the list of commits made on the HEAD but not included in
|
||||
experimental.
|
||||
|
||||
You can also give commits convenient names of your own: after running
|
||||
You can also give commits names of your own; after running
|
||||
|
||||
-------------------------------------
|
||||
$ git-tag v2.5 HEAD^^
|
||||
$ git-tag v2.5 1b2e1d63ff
|
||||
-------------------------------------
|
||||
|
||||
you can refer to HEAD^^ by the name "v2.5". If you intend to share
|
||||
this name with other people (for example, to identify a release
|
||||
you can refer to 1b2e1d63ff by the name "v2.5". If you intend to
|
||||
share this name with other people (for example, to identify a release
|
||||
version), you should create a "tag" object, and perhaps sign it; see
|
||||
gitlink:git-tag[1] for details.
|
||||
|
||||
You can revisit the old state of a tree, and make further
|
||||
modifications if you wish, using git branch: the command
|
||||
Any git command that needs to know a commit can take any of these
|
||||
names. For example:
|
||||
|
||||
-------------------------------------
|
||||
$ git branch stable-release v2.5
|
||||
$ git diff v2.5 HEAD # compare the current HEAD to v2.5
|
||||
$ git branch stable v2.5 # start a new branch named "stable" based
|
||||
# at v2.5
|
||||
$ git reset --hard HEAD^ # reset your current branch and working
|
||||
# directory its state at HEAD^
|
||||
-------------------------------------
|
||||
|
||||
will create a new branch named "stable-release" starting from the
|
||||
commit which you tagged with the name v2.5.
|
||||
|
||||
You can reset the state of any branch to an earlier commit at any
|
||||
time with
|
||||
|
||||
-------------------------------------
|
||||
$ git reset --hard v2.5
|
||||
-------------------------------------
|
||||
|
||||
This will remove all later commits from this branch and reset the
|
||||
working tree to the state it had when the given commit was made. If
|
||||
this branch is the only branch containing the later commits, those
|
||||
later changes will be lost. Don't use "git reset" on a
|
||||
Be careful with that last command: in addition to losing any changes
|
||||
in the working directory, it will also remove all later commits from
|
||||
this branch. If this branch is the only branch containing those
|
||||
commits, they will be lost. (Also, don't use "git reset" on a
|
||||
publicly-visible branch that other developers pull from, as git will
|
||||
be confused by history that disappears in this way.
|
||||
be confused by history that disappears in this way.)
|
||||
|
||||
The git grep command can search for strings in any version of your
|
||||
project, so
|
||||
|
||||
-------------------------------------
|
||||
$ git grep "hello" v2.5
|
||||
-------------------------------------
|
||||
|
||||
searches for all occurences of "hello" in v2.5.
|
||||
|
||||
If you leave out the commit name, git grep will search any of the
|
||||
files it manages in your current directory. So
|
||||
|
||||
-------------------------------------
|
||||
$ git grep "hello"
|
||||
-------------------------------------
|
||||
|
||||
is a quick way to search just the files that are tracked by git.
|
||||
|
||||
Many git commands also take sets of commits, which can be specified
|
||||
in a number of ways. Here are some examples with git log:
|
||||
|
||||
-------------------------------------
|
||||
$ git log v2.5..v2.6 # commits between v2.5 and v2.6
|
||||
$ git log v2.5.. # commits since v2.5
|
||||
$ git log --since="2 weeks ago" # commits from the last 2 weeks
|
||||
$ git log v2.5.. Makefile # commits since v2.5 which modify
|
||||
# Makefile
|
||||
-------------------------------------
|
||||
|
||||
You can also give git log a "range" of commits where the first is not
|
||||
necessarily an ancestor of the second; for example, if the tips of
|
||||
the branches "stable-release" and "master" diverged from a common
|
||||
commit some time ago, then
|
||||
|
||||
-------------------------------------
|
||||
$ git log stable..experimental
|
||||
-------------------------------------
|
||||
|
||||
will list commits made in the experimental branch but not in the
|
||||
stable branch, while
|
||||
|
||||
-------------------------------------
|
||||
$ git log experimental..stable
|
||||
-------------------------------------
|
||||
|
||||
will show the list of commits made on the stable branch but not
|
||||
the experimental branch.
|
||||
|
||||
The "git log" command has a weakness: it must present commits in a
|
||||
list. When the history has lines of development that diverged and
|
||||
then merged back together, the order in which "git log" presents
|
||||
those commits is meaningless.
|
||||
|
||||
Most projects with multiple contributors (such as the linux kernel,
|
||||
or git itself) have frequent merges, and gitk does a better job of
|
||||
visualizing their history. For example,
|
||||
|
||||
-------------------------------------
|
||||
$ gitk --since="2 weeks ago" drivers/
|
||||
-------------------------------------
|
||||
|
||||
allows you to browse any commits from the last 2 weeks of commits
|
||||
that modified files under the "drivers" directory.
|
||||
|
||||
Finally, most commands that take filenames will optionally allow you
|
||||
to precede any filename by a commit, to specify a particular version
|
||||
fo the file:
|
||||
|
||||
-------------------------------------
|
||||
$ git diff v2.5:Makefile HEAD:Makefile.in
|
||||
-------------------------------------
|
||||
|
||||
Next Steps
|
||||
----------
|
||||
|
||||
Some good commands to explore next:
|
||||
This tutorial should be enough to perform basic distributed revision
|
||||
control for your projects. However, to fully understand the depth
|
||||
and power of git you need to understand two simple ideas on which it
|
||||
is based:
|
||||
|
||||
* gitlink:git-diff[1]: This flexible command does much more than
|
||||
we've seen in the few examples above.
|
||||
* The object database is the rather elegant system used to
|
||||
store the history of your project--files, directories, and
|
||||
commits.
|
||||
|
||||
* The index file is a cache of the state of a directory tree,
|
||||
used to create commits, check out working directories, and
|
||||
hold the various trees involved in a merge.
|
||||
|
||||
link:tutorial-2.html[Part two of this tutorial] explains the object
|
||||
database, the index file, and a few other odds and ends that you'll
|
||||
need to make the most of git.
|
||||
|
||||
If you don't want to consider with that right away, a few other
|
||||
digressions that may be interesting at this point are:
|
||||
|
||||
* gitlink:git-format-patch[1], gitlink:git-am[1]: These convert
|
||||
series of git commits into emailed patches, and vice versa,
|
||||
@@ -397,8 +474,6 @@ Some good commands to explore next:
|
||||
smart enough to perform a close-to-optimal search even in the
|
||||
case of complex non-linear history with lots of merged branches.
|
||||
|
||||
Other good starting points include link:everyday.html[Everday GIT
|
||||
with 20 Commands Or So] and link:cvs-migration.html[git for CVS
|
||||
users]. Also, link:core-tutorial.html[A short git tutorial] gives an
|
||||
introduction to lower-level git commands for advanced users and
|
||||
developers.
|
||||
* link:everyday.html[Everday GIT with 20 Commands Or So]
|
||||
|
||||
* link:cvs-migration.html[git for CVS users].
|
||||
|
||||
Reference in New Issue
Block a user