SYNOPSIS
--------
-'git-diff' [ --diff-options ] <
ent>{0,2} [<path>...]
+'git-diff' [ --diff-options ] <
commit>{0,2} [--] [<path>...]
DESCRIPTION
-----------
-Show changes between two ents, an ent and the working tree, an
-ent and the index file, or the index file and the working tree.
-The combination of what is compared with what is determined by
-the number of ents given to the command.
+Show changes between two trees, a tree and the working tree, a
+tree and the index file, or the index file and the working tree.
-* When no <ent> is given, the working tree and the index
- file is compared, using `git-diff-files`.
+'git-diff' [--options] [--] [<path>...]::
-* When one <ent> is given, the working tree and the named
- tree is compared, using `git-diff-index`. The option
- `--cached` can be given to compare the index file and
- the named tree.
+ This form is to view the changes you made relative to
+ the index (staging area for the next commit). In other
+ words, the differences are what you _could_ tell git to
+ further add to the index but you still haven't. You can
+ stage these changes by using gitlink:git-add[1].
+
+'git-diff' [--options] --cached [<commit>] [--] [<path>...]::
+
+ This form is to view the changes you staged for the next
+ commit relative to the named <commit>. Typically you
+ would want comparison with the latest commit, so if you
+ do not give <commit>, it defaults to HEAD.
+
+'git-diff' [--options] <commit> [--] [<path>...]::
+
+ This form is to view the changes you have in your
+ working tree relative to the named <commit>. You can
+ use HEAD to compare it with the latest commit, or a
+ branch name to compare with the tip of a different
+ branch.
+
+'git-diff' [--options] <commit> <commit> [--] [<path>...]::
+
+ This form is to view the changes between two <commit>,
+ for example, tips of two branches.
+
+Just in case if you are doing something exotic, it should be
+noted that all of the <commit> in the above description can be
+any <tree-ish>.
+
+For a more complete list of ways to spell <commit>, see
+"SPECIFYING REVISIONS" section in gitlink:git-rev-parse[1].
-* When two <ent>s are given, these two trees are compared
- using `git-diff-tree`.
OPTIONS
-------
---diff-options::
- '--diff-options' are passed to the `git-diff-files`,
- `git-diff-index`, and `git-diff-tree` commands. See the
- documentation for these commands for description.
+include::diff-options.txt[]
<path>...::
- The <path> arguments are also passed to `git-diff-\*`
- commands.
+ The <paths> parameters, when given, are used to limit
+ the diff to the named paths (you can give directory
+ names and get diff for all files under them).
EXAMPLES
Various ways to check your working tree::
+
------------
-$ git diff <1>
-$ git diff --cached <2>
-$ git diff HEAD <3>
-
-<1> changes in the working tree since your last git-update-index.
+$ git diff <1>
+$ git diff --cached <2>
+$ git diff HEAD <3>
+------------
++
+<1> changes in the working tree not yet staged for the next commit.
<2> changes between the index and your last commit; what you
would be committing if you run "git commit" without "-a" option.
<3> changes in the working tree since your last commit; what you
would be committing if you run "git commit -a"
-------------
Comparing with arbitrary commits::
+
------------
-$ git diff test <1>
-$ git diff HEAD -- ./test <2>
-$ git diff HEAD^ HEAD <3>
-
+$ git diff test <1>
+$ git diff HEAD -- ./test <2>
+$ git diff HEAD^ HEAD <3>
+------------
++
<1> instead of using the tip of the current branch, compare with the
tip of "test" branch.
<2> instead of comparing with the tip of "test" branch, compare with
the tip of the current branch, but limit the comparison to the
file "test".
<3> compare the version before the last commit and the last commit.
-------------
Limiting the diff output::
+
------------
-$ git diff --diff-filter=MRC <1>
-$ git diff --name-status -r <2>
-$ git diff arch/i386 include/asm-i386 <3>
-
+$ git diff --diff-filter=MRC <1>
+$ git diff --name-status -r <2>
+$ git diff arch/i386 include/asm-i386 <3>
+------------
++
<1> show only modification, rename and copy, but not addition
nor deletion.
<2> show only names and the nature of change, but not actual
diff output. --name-status disables usual patch generation
-which in turn also disables recursive behaviour, so without -r
+which in turn also disables recursive behavior, so without -r
you would only see the directory name if there is a change in a
file in a subdirectory.
<3> limit diff output to named subtrees.
-------------
Munging the diff output::
+
------------
-$ git diff --find-copies-harder -B -C <1>
-$ git diff -R <2>
-
+$ git diff --find-copies-harder -B -C <1>
+$ git diff -R <2>
+------------
++
<1> spend extra cycles to find renames, copies and complete
rewrites (very expensive).
<2> output diff in reverse.
-------------
Author