[PATCH] Expose object ID computation functions.

[thirdparty/git.git] / Documentation / git-diff-tree.txt

git-diff-tree(1)
================
v0.1, May 2005

NAME
----
git-diff-tree - Compares the content and mode of blobs found via two tree objects


SYNOPSIS
--------
'git-diff-tree' [-p] [-r] [-z] [--stdin] [-m] [-s] [-v] [-t] [-R] [-B] [-M] [-C] [--find-copies-harder] [-O<orderfile>] [-S<string>] [--pickaxe-all] <tree-ish> <tree-ish> [<path>...]

DESCRIPTION
-----------
Compares the content and mode of the blobs found via two tree objects.

Note that "git-diff-tree" can use the tree encapsulated in a commit object.

OPTIONS
-------
<tree-ish>::
	The id of a tree object.

<path>...::
	If provided, the results are limited to a subset of files
	matching one of these prefix strings.
	ie file matches `/^<pattern1>|<pattern2>|.../`
	Note that this parameter does not provide any wildcard or regexp
	features.

-p::
	generate patch (see section on generating patches).  For
	git-diff-tree, this flag implies '-r' as well.

-B::
	Break complete rewrite changes into pairs of delete and create.

-M::
	Detect renames.

-C::
	Detect copies as well as renames.

--find-copies-harder::
	By default, -C option finds copies only if the original
	file of the copy was modified in the same changeset for
	performance reasons.  This flag makes the command
	inspect unmodified files as candidates for the source of
	copy.  This is a very expensive operation for large
	projects, so use it with caution.

-R::
	Swap two input trees.

-S<string>::
	Look for differences that contains the change in <string>.

--pickaxe-all::
	When -S finds a change, show all the changes in that
	changeset, not just the files that contains the change
	in <string>.

-O<orderfile>::
	Output the patch in the order specified in the
	<orderfile>, which has one shell glob pattern per line.

-r::
	recurse

-t::
	show tree entry itself as well as subtrees.  Implies -r.

-z::
	\0 line termination on output

--root::
	When '--root' is specified the initial commit will be showed as a big
	creation event. This is equivalent to a diff against the NULL tree.

--stdin::
	When '--stdin' is specified, the command does not take
	<tree-ish> arguments from the command line.  Instead, it
	reads either one <commit> or a pair of <tree-ish>
	separated with a single space from its standard input.
+
When a single commit is given on one line of such input, it compares
the commit with its parents.  The following flags further affects its
behaviour.  This does not apply to the case where two <tree-ish>
separated with a single space are given.

-m::
	By default, "git-diff-tree --stdin" does not show
	differences for merge commits.  With this flag, it shows
	differences to that commit from all of its parents.

-s::
	By default, "git-diff-tree --stdin" shows differences,
	either in machine-readable form (without '-p') or in patch
	form (with '-p').  This output can be supressed.  It is
	only useful with '-v' flag.

-v::
	This flag causes "git-diff-tree --stdin" to also show
	the commit message before the differences.

--pretty[=(raw|medium|short)]::
	This is used to control "pretty printing" format of the
	commit message.  Without "=<style>", it defaults to
	medium.


Limiting Output
---------------
If you're only interested in differences in a subset of files, for
example some architecture-specific files, you might do:

	git-diff-tree -r <tree-ish> <tree-ish> arch/ia64 include/asm-ia64

and it will only show you what changed in those two directories.

Or if you are searching for what changed in just `kernel/sched.c`, just do

	git-diff-tree -r <tree-ish> <tree-ish> kernel/sched.c

and it will ignore all differences to other files.

The pattern is always the prefix, and is matched exactly.  There are no
wildcards.  Even stricter, it has to match complete path comonent.
I.e. "foo" does not pick up `foobar.h`.  "foo" does match `foo/bar.h`
so it can be used to name subdirectories.

An example of normal usage is:

  torvalds@ppc970:~/git> git-diff-tree 5319e4......
  *100664->100664 blob    ac348b.......->a01513.......      git-fsck-cache.c

which tells you that the last commit changed just one file (it's from
this one:

  commit 3c6f7ca19ad4043e9e72fa94106f352897e651a8
  tree 5319e4d609cdd282069cc4dce33c1db559539b03
  parent b4e628ea30d5ab3606119d2ea5caeab141d38df7
  author Linus Torvalds <torvalds@ppc970.osdl.org> Sat Apr 9 12:02:30 2005
  committer Linus Torvalds <torvalds@ppc970.osdl.org> Sat Apr 9 12:02:30 2005

  Make "git-fsck-cache" print out all the root commits it finds.

  Once I do the reference tracking, I'll also make it print out all the
  HEAD commits it finds, which is even more interesting.

in case you care).

Output format
-------------
include::diff-format.txt[]


Author
------
Written by Linus Torvalds <torvalds@osdl.org>

Documentation
--------------
Documentation by David Greaves, Junio C Hamano and the git-list <git@vger.kernel.org>.

GIT
---
Part of the link:git.html[git] suite