Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
GIT-DIFF-INDEX(1)		  Git Manual		     GIT-DIFF-INDEX(1)

NAME
       git-diff-index -	Compare	a tree to the working tree or index

SYNOPSIS
       git diff-index [-m] [--cached] [<common diff options>] <tree-ish> [<path>...]

DESCRIPTION
       Compares	the content and	mode of	the blobs found	in a tree object with
       the corresponding tracked files in the working tree, or with the
       corresponding paths in the index. When <path> arguments are present,
       compares	only paths matching those patterns. Otherwise all tracked
       files are compared.

OPTIONS
       -p, -u, --patch
	   Generate patch (see section on generating patches).

       -s, --no-patch
	   Suppress diff output. Useful	for commands like git show that	show
	   the patch by	default, or to cancel the effect of --patch.

       -U<n>, --unified=<n>
	   Generate diffs with <n> lines of context instead of the usual
	   three. Implies -p.

       --raw
	   Generate the	diff in	raw format. This is the	default.

       --patch-with-raw
	   Synonym for -p --raw.

       --indent-heuristic, --no-indent-heuristic
	   These are to	help debugging and tuning experimental heuristics
	   (which are off by default) that shift diff hunk boundaries to make
	   patches easier to read.

       --minimal
	   Spend extra time to make sure the smallest possible diff is
	   produced.

       --patience
	   Generate a diff using the "patience diff" algorithm.

       --histogram
	   Generate a diff using the "histogram	diff" algorithm.

       --diff-algorithm={patience|minimal|histogram|myers}
	   Choose a diff algorithm. The	variants are as	follows:

	   default, myers
	       The basic greedy	diff algorithm.	Currently, this	is the
	       default.

	   minimal
	       Spend extra time	to make	sure the smallest possible diff	is
	       produced.

	   patience
	       Use "patience diff" algorithm when generating patches.

	   histogram
	       This algorithm extends the patience algorithm to	"support
	       low-occurrence common elements".

	   For instance, if you	configured diff.algorithm variable to a
	   non-default value and want to use the default one, then you have to
	   use --diff-algorithm=default	option.

       --stat[=<width>[,<name-width>[,<count>]]]
	   Generate a diffstat.	By default, as much space as necessary will be
	   used	for the	filename part, and the rest for	the graph part.
	   Maximum width defaults to terminal width, or	80 columns if not
	   connected to	a terminal, and	can be overridden by <width>. The
	   width of the	filename part can be limited by	giving another width
	   <name-width>	after a	comma. The width of the	graph part can be
	   limited by using --stat-graph-width=<width> (affects	all commands
	   generating a	stat graph) or by setting diff.statGraphWidth=<width>
	   (does not affect git	format-patch). By giving a third parameter
	   <count>, you	can limit the output to	the first <count> lines,
	   followed by ...  if there are more.

	   These parameters can	also be	set individually with
	   --stat-width=<width>, --stat-name-width=<name-width>	and
	   --stat-count=<count>.

       --numstat
	   Similar to --stat, but shows	number of added	and deleted lines in
	   decimal notation and	pathname without abbreviation, to make it more
	   machine friendly. For binary	files, outputs two - instead of	saying
	   0 0.

       --shortstat
	   Output only the last	line of	the --stat format containing total
	   number of modified files, as	well as	number of added	and deleted
	   lines.

       --dirstat[=<param1,param2,...>]
	   Output the distribution of relative amount of changes for each
	   sub-directory. The behavior of --dirstat can	be customized by
	   passing it a	comma separated	list of	parameters. The	defaults are
	   controlled by the diff.dirstat configuration	variable (see git-
	   config(1)). The following parameters	are available:

	   changes
	       Compute the dirstat numbers by counting the lines that have
	       been removed from the source, or	added to the destination. This
	       ignores the amount of pure code movements within	a file.	In
	       other words, rearranging	lines in a file	is not counted as much
	       as other	changes. This is the default behavior when no
	       parameter is given.

	   lines
	       Compute the dirstat numbers by doing the	regular	line-based
	       diff analysis, and summing the removed/added line counts. (For
	       binary files, count 64-byte chunks instead, since binary	files
	       have no natural concept of lines). This is a more expensive
	       --dirstat behavior than the changes behavior, but it does count
	       rearranged lines	within a file as much as other changes.	The
	       resulting output	is consistent with what	you get	from the other
	       --*stat options.

	   files
	       Compute the dirstat numbers by counting the number of files
	       changed.	Each changed file counts equally in the	dirstat
	       analysis. This is the computationally cheapest --dirstat
	       behavior, since it does not have	to look	at the file contents
	       at all.

	   cumulative
	       Count changes in	a child	directory for the parent directory as
	       well. Note that when using cumulative, the sum of the
	       percentages reported may	exceed 100%. The default
	       (non-cumulative)	behavior can be	specified with the
	       noncumulative parameter.

	   <limit>
	       An integer parameter specifies a	cut-off	percent	(3% by
	       default). Directories contributing less than this percentage of
	       the changes are not shown in the	output.

	   Example: The	following will count changed files, while ignoring
	   directories with less than 10% of the total amount of changed
	   files, and accumulating child directory counts in the parent
	   directories:	--dirstat=files,10,cumulative.

       --summary
	   Output a condensed summary of extended header information such as
	   creations, renames and mode changes.

       --patch-with-stat
	   Synonym for -p --stat.

       -z
	   When	--raw, --numstat, --name-only or --name-status has been	given,
	   do not munge	pathnames and use NULs as output field terminators.

	   Without this	option,	pathnames with "unusual" characters are	quoted
	   as explained	for the	configuration variable core.quotePath (see
	   git-config(1)).

       --name-only
	   Show	only names of changed files.

       --name-status
	   Show	only names and status of changed files.	See the	description of
	   the --diff-filter option on what the	status letters mean.

       --submodule[=<format>]
	   Specify how differences in submodules are shown. When specifying
	   --submodule=short the short format is used. This format just	shows
	   the names of	the commits at the beginning and end of	the range.
	   When	--submodule or --submodule=log is specified, the log format is
	   used. This format lists the commits in the range like git-
	   submodule(1)summary does. When --submodule=diff is specified, the
	   diff	format is used.	This format shows an inline diff of the
	   changes in the submodule contents between the commit	range.
	   Defaults to diff.submodule or the short format if the config	option
	   is unset.

       --color[=<when>]
	   Show	colored	diff.  --color (i.e. without =_when_) is the same as
	   --color=always.  _when_ can be one of always, never,	or auto.

       --no-color
	   Turn	off colored diff. It is	the same as --color=never.

       --word-diff[=<mode>]
	   Show	a word diff, using the <mode> to delimit changed words.	By
	   default, words are delimited	by whitespace; see --word-diff-regex
	   below. The <mode> defaults to plain,	and must be one	of:

	   color
	       Highlight changed words using only colors. Implies --color.

	   plain
	       Show words as [-removed-] and {+added+}.	Makes no attempts to
	       escape the delimiters if	they appear in the input, so the
	       output may be ambiguous.

	   porcelain
	       Use a special line-based	format intended	for script
	       consumption. Added/removed/unchanged runs are printed in	the
	       usual unified diff format, starting with	a +/-/`	` character at
	       the beginning of	the line and extending to the end of the line.
	       Newlines	in the input are represented by	a tilde	~ on a line of
	       its own.

	   none
	       Disable word diff again.

	   Note	that despite the name of the first mode, color is used to
	   highlight the changed parts in all modes if enabled.

       --word-diff-regex=<regex>
	   Use <regex> to decide what a	word is, instead of considering	runs
	   of non-whitespace to	be a word. Also	implies	--word-diff unless it
	   was already enabled.

	   Every non-overlapping match of the <regex> is considered a word.
	   Anything between these matches is considered	whitespace and
	   ignored(!) for the purposes of finding differences. You may want to
	   append |[^[:space:]]	to your	regular	expression to make sure	that
	   it matches all non-whitespace characters. A match that contains a
	   newline is silently truncated(!) at the newline.

	   For example,	--word-diff-regex=.  will treat	each character as a
	   word	and, correspondingly, show differences character by character.

	   The regex can also be set via a diff	driver or configuration
	   option, see gitattributes(5)	or git-config(1). Giving it explicitly
	   overrides any diff driver or	configuration setting. Diff drivers
	   override configuration settings.

       --color-words[=<regex>]
	   Equivalent to --word-diff=color plus	(if a regex was	specified)
	   --word-diff-regex=<regex>.

       --no-renames
	   Turn	off rename detection, even when	the configuration file gives
	   the default to do so.

       --check
	   Warn	if changes introduce conflict markers or whitespace errors.
	   What	are considered whitespace errors is controlled by
	   core.whitespace configuration. By default, trailing whitespaces
	   (including lines that solely	consist	of whitespaces)	and a space
	   character that is immediately followed by a tab character inside
	   the initial indent of the line are considered whitespace errors.
	   Exits with non-zero status if problems are found. Not compatible
	   with	--exit-code.

       --ws-error-highlight=<kind>
	   Highlight whitespace	errors on lines	specified by <kind> in the
	   color specified by color.diff.whitespace. <kind> is a comma
	   separated list of old, new, context.	When this option is not	given,
	   only	whitespace errors in new lines are highlighted.	E.g.
	   --ws-error-highlight=new,old	highlights whitespace errors on	both
	   deleted and added lines.  all can be	used as	a short-hand for
	   old,new,context. The	diff.wsErrorHighlight configuration variable
	   can be used to specify the default behaviour.

       --full-index
	   Instead of the first	handful	of characters, show the	full pre- and
	   post-image blob object names	on the "index" line when generating
	   patch format	output.

       --binary
	   In addition to --full-index,	output a binary	diff that can be
	   applied with	git-apply.

       --abbrev[=<n>]
	   Instead of showing the full 40-byte hexadecimal object name in
	   diff-raw format output and diff-tree	header lines, show only	a
	   partial prefix. This	is independent of the --full-index option
	   above, which	controls the diff-patch	output format. Non default
	   number of digits can	be specified with --abbrev=<n>.

       -B[<n>][/<m>], --break-rewrites[=[<n>][/<m>]]
	   Break complete rewrite changes into pairs of	delete and create.
	   This	serves two purposes:

	   It affects the way a	change that amounts to a total rewrite of a
	   file	not as a series	of deletion and	insertion mixed	together with
	   a very few lines that happen	to match textually as the context, but
	   as a	single deletion	of everything old followed by a	single
	   insertion of	everything new,	and the	number m controls this aspect
	   of the -B option (defaults to 60%).	-B/70% specifies that less
	   than	30% of the original should remain in the result	for Git	to
	   consider it a total rewrite (i.e. otherwise the resulting patch
	   will	be a series of deletion	and insertion mixed together with
	   context lines).

	   When	used with -M, a	totally-rewritten file is also considered as
	   the source of a rename (usually -M only considers a file that
	   disappeared as the source of	a rename), and the number n controls
	   this	aspect of the -B option	(defaults to 50%).  -B20% specifies
	   that	a change with addition and deletion compared to	20% or more of
	   the file's size are eligible	for being picked up as a possible
	   source of a rename to another file.

       -M[<n>],	--find-renames[=<n>]
	   Detect renames. If n	is specified, it is a threshold	on the
	   similarity index (i.e. amount of addition/deletions compared	to the
	   file's size). For example, -M90% means Git should consider a
	   delete/add pair to be a rename if more than 90% of the file hasn't
	   changed. Without a %	sign, the number is to be read as a fraction,
	   with	a decimal point	before it. I.e., -M5 becomes 0.5, and is thus
	   the same as -M50%. Similarly, -M05 is the same as -M5%. To limit
	   detection to	exact renames, use -M100%. The default similarity
	   index is 50%.

       -C[<n>],	--find-copies[=<n>]
	   Detect copies as well as renames. See also --find-copies-harder. If
	   n is	specified, it has the same meaning as for -M<n>.

       --find-copies-harder
	   For performance reasons, by default,	-C option finds	copies only if
	   the original	file of	the copy was modified in the same changeset.
	   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. Giving more than one	-C
	   option has the same effect.

       -D, --irreversible-delete
	   Omit	the preimage for deletes, i.e. print only the header but not
	   the diff between the	preimage and /dev/null.	The resulting patch is
	   not meant to	be applied with	patch or git apply; this is solely for
	   people who want to just concentrate on reviewing the	text after the
	   change. In addition,	the output obviously lack enough information
	   to apply such a patch in reverse, even manually, hence the name of
	   the option.

	   When	used together with -B, omit also the preimage in the deletion
	   part	of a delete/create pair.

       -l<num>
	   The -M and -C options require O(n^2)	processing time	where n	is the
	   number of potential rename/copy targets. This option	prevents
	   rename/copy detection from running if the number of rename/copy
	   targets exceeds the specified number.

       --diff-filter=[(A|C|D|M|R|T|U|X|B)...[*]]
	   Select only files that are Added (A), Copied	(C), Deleted (D),
	   Modified (M), Renamed (R), have their type (i.e. regular file,
	   symlink, submodule, ...) changed (T), are Unmerged (U), are Unknown
	   (X),	or have	had their pairing Broken (B). Any combination of the
	   filter characters (including	none) can be used. When	*
	   (All-or-none) is added to the combination, all paths	are selected
	   if there is any file	that matches other criteria in the comparison;
	   if there is no file that matches other criteria, nothing is
	   selected.

	   Also, these upper-case letters can be downcased to exclude. E.g.
	   --diff-filter=ad excludes added and deleted paths.

       -S<string>
	   Look	for differences	that change the	number of occurrences of the
	   specified string (i.e. addition/deletion) in	a file.	Intended for
	   the scripter's use.

	   It is useful	when you're looking for	an exact block of code (like a
	   struct), and	want to	know the history of that block since it	first
	   came	into being: use	the feature iteratively	to feed	the
	   interesting block in	the preimage back into -S, and keep going
	   until you get the very first	version	of the block.

       -G<regex>
	   Look	for differences	whose patch text contains added/removed	lines
	   that	match <regex>.

	   To illustrate the difference	between	-S<regex> --pickaxe-regex and
	   -G<regex>, consider a commit	with the following diff	in the same
	   file:

	       +    return !regexec(regexp, two->ptr, 1, &regmatch, 0);
	       ...
	       -    hit	= !regexec(regexp, mf2.ptr, 1, &regmatch, 0);

	   While git log -G"regexec\(regexp" will show this commit, git	log
	   -S"regexec\(regexp" --pickaxe-regex will not	(because the number of
	   occurrences of that string did not change).

	   See the pickaxe entry in gitdiffcore(7) for more information.

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

       --pickaxe-regex
	   Treat the <string> given to -S as an	extended POSIX regular
	   expression to match.

       -O<orderfile>
	   Control the order in	which files appear in the output. This
	   overrides the diff.orderFile	configuration variable (see git-
	   config(1)). To cancel diff.orderFile, use -O/dev/null.

	   The output order is determined by the order of glob patterns	in
	   <orderfile>.	All files with pathnames that match the	first pattern
	   are output first, all files with pathnames that match the second
	   pattern (but	not the	first) are output next,	and so on. All files
	   with	pathnames that do not match any	pattern	are output last, as if
	   there was an	implicit match-all pattern at the end of the file. If
	   multiple pathnames have the same rank (they match the same pattern
	   but no earlier patterns), their output order	relative to each other
	   is the normal order.

	   <orderfile> is parsed as follows:

	   o   Blank lines are ignored,	so they	can be used as separators for
	       readability.

	   o   Lines starting with a hash ("#")	are ignored, so	they can be
	       used for	comments. Add a	backslash ("\")	to the beginning of
	       the pattern if it starts	with a hash.

	   o   Each other line contains	a single pattern.

	   Patterns have the same syntax and semantics as patterns used	for
	   fnmantch(3) without the FNM_PATHNAME	flag, except a pathname	also
	   matches a pattern if	removing any number of the final pathname
	   components matches the pattern. For example,	the pattern "foo*bar"
	   matches "fooasdfbar"	and "foo/bar/baz/asdf" but not "foobarx".

       -R
	   Swap	two inputs; that is, show differences from index or on-disk
	   file	to tree	contents.

       --relative[=<path>]
	   When	run from a subdirectory	of the project,	it can be told to
	   exclude changes outside the directory and show pathnames relative
	   to it with this option. When	you are	not in a subdirectory (e.g. in
	   a bare repository), you can name which subdirectory to make the
	   output relative to by giving	a <path> as an argument.

       -a, --text
	   Treat all files as text.

       --ignore-space-at-eol
	   Ignore changes in whitespace	at EOL.

       -b, --ignore-space-change
	   Ignore changes in amount of whitespace. This	ignores	whitespace at
	   line	end, and considers all other sequences of one or more
	   whitespace characters to be equivalent.

       -w, --ignore-all-space
	   Ignore whitespace when comparing lines. This	ignores	differences
	   even	if one line has	whitespace where the other line	has none.

       --ignore-blank-lines
	   Ignore changes whose	lines are all blank.

       --inter-hunk-context=<lines>
	   Show	the context between diff hunks,	up to the specified number of
	   lines, thereby fusing hunks that are	close to each other. Defaults
	   to diff.interHunkContext or 0 if the	config option is unset.

       -W, --function-context
	   Show	whole surrounding functions of changes.

       --exit-code
	   Make	the program exit with codes similar to diff(1).	That is, it
	   exits with 1	if there were differences and 0	means no differences.

       --quiet
	   Disable all output of the program. Implies --exit-code.

       --ext-diff
	   Allow an external diff helper to be executed. If you	set an
	   external diff driver	with gitattributes(5), you need	to use this
	   option with git-log(1) and friends.

       --no-ext-diff
	   Disallow external diff drivers.

       --textconv, --no-textconv
	   Allow (or disallow) external	text conversion	filters	to be run when
	   comparing binary files. See gitattributes(5)	for details. Because
	   textconv filters are	typically a one-way conversion,	the resulting
	   diff	is suitable for	human consumption, but cannot be applied. For
	   this	reason,	textconv filters are enabled by	default	only for git-
	   diff(1) and git-log(1), but not for git-format-patch(1) or diff
	   plumbing commands.

       --ignore-submodules[=<when>]
	   Ignore changes to submodules	in the diff generation.	<when> can be
	   either "none", "untracked", "dirty" or "all", which is the default.
	   Using "none"	will consider the submodule modified when it either
	   contains untracked or modified files	or its HEAD differs from the
	   commit recorded in the superproject and can be used to override any
	   settings of the ignore option in git-config(1) or gitmodules(5).
	   When	"untracked" is used submodules are not considered dirty	when
	   they	only contain untracked content (but they are still scanned for
	   modified content). Using "dirty" ignores all	changes	to the work
	   tree	of submodules, only changes to the commits stored in the
	   superproject	are shown (this	was the	behavior until 1.7.0). Using
	   "all" hides all changes to submodules.

       --src-prefix=<prefix>
	   Show	the given source prefix	instead	of "a/".

       --dst-prefix=<prefix>
	   Show	the given destination prefix instead of	"b/".

       --no-prefix
	   Do not show any source or destination prefix.

       --line-prefix=<prefix>
	   Prepend an additional prefix	to every line of output.

       --ita-invisible-in-index
	   By default entries added by "git add	-N" appear as an existing
	   empty file in "git diff" and	a new file in "git diff	--cached".
	   This	option makes the entry appear as a new file in "git diff" and
	   non-existent	in "git	diff --cached".	This option could be reverted
	   with	--ita-visible-in-index.	Both options are experimental and
	   could be removed in future.

       For more	detailed explanation on	these common options, see also
       gitdiffcore(7).

       <tree-ish>
	   The id of a tree object to diff against.

       --cached
	   do not consider the on-disk file at all

       -m
	   By default, files recorded in the index but not checked out are
	   reported as deleted.	This flag makes	git diff-index say that	all
	   non-checked-out files are up	to date.

RAW OUTPUT FORMAT
       The raw output format from "git-diff-index", "git-diff-tree",
       "git-diff-files"	and "git diff --raw" are very similar.

       These commands all compare two sets of things; what is compared
       differs:

       git-diff-index <tree-ish>
	   compares the	<tree-ish> and the files on the	filesystem.

       git-diff-index --cached <tree-ish>
	   compares the	<tree-ish> and the index.

       git-diff-tree [-r] <tree-ish-1> <tree-ish-2> [<pattern>...]
	   compares the	trees named by the two arguments.

       git-diff-files [<pattern>...]
	   compares the	index and the files on the filesystem.

       The "git-diff-tree" command begins its output by	printing the hash of
       what is being compared. After that, all the commands print one output
       line per	changed	file.

       An output line is formatted this	way:

	   in-place edit  :100644 100644 bcd1234... 0123456... M file0
	   copy-edit	  :100644 100644 abcd123... 1234567... C68 file1 file2
	   rename-edit	  :100644 100644 abcd123... 1234567... R86 file1 file3
	   create	  :000000 100644 0000000... 1234567... A file4
	   delete	  :100644 000000 1234567... 0000000... D file5
	   unmerged	  :000000 000000 0000000... 0000000... U file6

       That is,	from the left to the right:

	1. a colon.

	2. mode	for "src"; 000000 if creation or unmerged.

	3. a space.

	4. mode	for "dst"; 000000 if deletion or unmerged.

	5. a space.

	6. sha1	for "src"; 0{40} if creation or	unmerged.

	7. a space.

	8. sha1	for "dst"; 0{40} if creation, unmerged or "look	at work	tree".

	9. a space.

       10. status, followed by optional	"score"	number.

       11. a tab or a NUL when -z option is used.

       12. path	for "src"

       13. a tab or a NUL when -z option is used; only exists for C or R.

       14. path	for "dst"; only	exists for C or	R.

       15. an LF or a NUL when -z option is used, to terminate the record.

       Possible	status letters are:

       o   A: addition of a file

       o   C: copy of a	file into a new	one

       o   D: deletion of a file

       o   M: modification of the contents or mode of a	file

       o   R: renaming of a file

       o   T: change in	the type of the	file

       o   U: file is unmerged (you must complete the merge before it can be
	   committed)

       o   X: "unknown"	change type (most probably a bug, please report	it)

       Status letters C	and R are always followed by a score (denoting the
       percentage of similarity	between	the source and target of the move or
       copy). Status letter M may be followed by a score (denoting the
       percentage of dissimilarity) for	file rewrites.

       <sha1> is shown as all 0's if a file is new on the filesystem and it is
       out of sync with	the index.

       Example:

	   :100644 100644 5be4a4...... 000000...... M file.c

       Without the -z option, pathnames	with "unusual" characters are quoted
       as explained for	the configuration variable core.quotePath (see git-
       config(1)). Using -z the	filename is output verbatim and	the line is
       terminated by a NUL byte.

DIFF FORMAT FOR	MERGES
       "git-diff-tree",	"git-diff-files" and "git-diff --raw" can take -c or
       --cc option to generate diff output also	for merge commits. The output
       differs from the	format described above in the following	way:

	1. there is a colon for	each parent

	2. there are more "src"	modes and "src"	sha1

	3. status is concatenated status characters for	each parent

	4. no optional "score" number

	5. single path,	only for "dst"

       Example:

	   ::100644 100644 100644 fabadb8... cc95eb0...	4866510... MM	   describe.c

       Note that combined diff lists only files	which were modified from all
       parents.

GENERATING PATCHES WITH	-P
       When "git-diff-index", "git-diff-tree", or "git-diff-files" are run
       with a -p option, "git diff" without the	--raw option, or "git log"
       with the	"-p" option, they do not produce the output described above;
       instead they produce a patch file. You can customize the	creation of
       such patches via	the GIT_EXTERNAL_DIFF and the GIT_DIFF_OPTS
       environment variables.

       What the	-p option produces is slightly different from the traditional
       diff format:

	1. It is preceded with a "git diff" header that	looks like this:

	       diff --git a/file1 b/file2

	   The a/ and b/ filenames are the same	unless rename/copy is
	   involved. Especially, even for a creation or	a deletion, /dev/null
	   is not used in place	of the a/ or b/	filenames.

	   When	rename/copy is involved, file1 and file2 show the name of the
	   source file of the rename/copy and the name of the file that
	   rename/copy produces, respectively.

	2. It is followed by one or more extended header lines:

	       old mode	<mode>
	       new mode	<mode>
	       deleted file mode <mode>
	       new file	mode <mode>
	       copy from <path>
	       copy to <path>
	       rename from <path>
	       rename to <path>
	       similarity index	<number>
	       dissimilarity index <number>
	       index <hash>..<hash> <mode>

	   File	modes are printed as 6-digit octal numbers including the file
	   type	and file permission bits.

	   Path	names in extended headers do not include the a/	and b/
	   prefixes.

	   The similarity index	is the percentage of unchanged lines, and the
	   dissimilarity index is the percentage of changed lines. It is a
	   rounded down	integer, followed by a percent sign. The similarity
	   index value of 100% is thus reserved	for two	equal files, while
	   100%	dissimilarity means that no line from the old file made	it
	   into	the new	one.

	   The index line includes the SHA-1 checksum before and after the
	   change. The <mode> is included if the file mode does	not change;
	   otherwise, separate lines indicate the old and the new mode.

	3. Pathnames with "unusual" characters are quoted as explained for the
	   configuration variable core.quotePath (see git-config(1)).

	4. All the file1 files in the output refer to files before the commit,
	   and all the file2 files refer to files after	the commit. It is
	   incorrect to	apply each change to each file sequentially. For
	   example, this patch will swap a and b:

	       diff --git a/a b/b
	       rename from a
	       rename to b
	       diff --git a/b b/a
	       rename from b
	       rename to a

COMBINED DIFF FORMAT
       Any diff-generating command can take the	-c or --cc option to produce a
       combined	diff when showing a merge. This	is the default format when
       showing merges with git-diff(1) or git-show(1). Note also that you can
       give the	-m option to any of these commands to force generation of
       diffs with individual parents of	a merge.

       A combined diff format looks like this:

	   diff	--combined describe.c
	   index fabadb8,cc95eb0..4866510
	   --- a/describe.c
	   +++ b/describe.c
	   @@@ -98,20 -98,12 +98,20 @@@
		   return (a_date > b_date) ? -1 : (a_date == b_date) ?	0 : 1;
	     }

	   - static void describe(char *arg)
	    -static void describe(struct commit	*cmit, int last_one)
	   ++static void describe(char *arg, int last_one)
	     {
	    +	   unsigned char sha1[20];
	    +	   struct commit *cmit;
		   struct commit_list *list;
		   static int initialized = 0;
		   struct commit_name *n;

	    +	   if (get_sha1(arg, sha1) < 0)
	    +		   usage(describe_usage);
	    +	   cmit	= lookup_commit_reference(sha1);
	    +	   if (!cmit)
	    +		   usage(describe_usage);
	    +
		   if (!initialized) {
			   initialized = 1;
			   for_each_ref(get_name);

	1. It is preceded with a "git diff" header, that looks like this (when
	   -c option is	used):

	       diff --combined file

	   or like this	(when --cc option is used):

	       diff --cc file

	2. It is followed by one or more extended header lines (this example
	   shows a merge with two parents):

	       index <hash>,<hash>..<hash>
	       mode <mode>,<mode>..<mode>
	       new file	mode <mode>
	       deleted file mode <mode>,<mode>

	   The mode <mode>,<mode>..<mode> line appears only if at least	one of
	   the <mode> is different from	the rest. Extended headers with
	   information about detected contents movement	(renames and copying
	   detection) are designed to work with	diff of	two <tree-ish> and are
	   not used by combined	diff format.

	3. It is followed by two-line from-file/to-file	header

	       --- a/file
	       +++ b/file

	   Similar to two-line header for traditional unified diff format,
	   /dev/null is	used to	signal created or deleted files.

	4. Chunk header	format is modified to prevent people from accidentally
	   feeding it to patch -p1. Combined diff format was created for
	   review of merge commit changes, and was not meant for apply.	The
	   change is similar to	the change in the extended index header:

	       @@@ <from-file-range> <from-file-range> <to-file-range> @@@

	   There are (number of	parents	+ 1) @ characters in the chunk header
	   for combined	diff format.

       Unlike the traditional unified diff format, which shows two files A and
       B with a	single column that has - (minus	-- appears in A	but removed in
       B), + (plus -- missing in A but added to	B), or " " (space --
       unchanged) prefix, this format compares two or more files file1,
       file2,... with one file X, and shows how	X differs from each of fileN.
       One column for each of fileN is prepended to the	output line to note
       how X's line is different from it.

       A - character in	the column N means that	the line appears in fileN but
       it does not appear in the result. A + character in the column N means
       that the	line appears in	the result, and	fileN does not have that line
       (in other words,	the line was added, from the point of view of that
       parent).

       In the above example output, the	function signature was changed from
       both files (hence two - removals	from both file1	and file2, plus	++ to
       mean one	line that was added does not appear in either file1 or file2).
       Also eight other	lines are the same from	file1 but do not appear	in
       file2 (hence prefixed with +).

       When shown by git diff-tree -c, it compares the parents of a merge
       commit with the merge result (i.e. file1..fileN are the parents). When
       shown by	git diff-files -c, it compares the two unresolved merge
       parents with the	working	tree file (i.e.	file1 is stage 2 aka "our
       version", file2 is stage	3 aka "their version").

OTHER DIFF FORMATS
       The --summary option describes newly added, deleted, renamed and	copied
       files. The --stat option	adds diffstat(1) graph to the output. These
       options can be combined with other options, such	as -p, and are meant
       for human consumption.

       When showing a change that involves a rename or a copy, --stat output
       formats the pathnames compactly by combining common prefix and suffix
       of the pathnames. For example, a	change that moves arch/i386/Makefile
       to arch/x86/Makefile while modifying 4 lines will be shown like this:

	   arch/{i386 => x86}/Makefile	  |   4	+--

       The --numstat option gives the diffstat(1) information but is designed
       for easier machine consumption. An entry	in --numstat output looks like
       this:

	   1	   2	   README
	   3	   1	   arch/{i386 => x86}/Makefile

       That is,	from left to right:

	1. the number of added lines;

	2. a tab;

	3. the number of deleted lines;

	4. a tab;

	5. pathname (possibly with rename/copy information);

	6. a newline.

       When -z output option is	in effect, the output is formatted this	way:

	   1	   2	   README NUL
	   3	   1	   NUL arch/i386/Makefile NUL arch/x86/Makefile	NUL

       That is:

	1. the number of added lines;

	2. a tab;

	3. the number of deleted lines;

	4. a tab;

	5. a NUL (only exists if renamed/copied);

	6. pathname in preimage;

	7. a NUL (only exists if renamed/copied);

	8. pathname in postimage (only exists if renamed/copied);

	9. a NUL.

       The extra NUL before the	preimage path in renamed case is to allow
       scripts that read the output to tell if the current record being	read
       is a single-path	record or a rename/copy	record without reading ahead.
       After reading added and deleted lines, reading up to NUL	would yield
       the pathname, but if that is NUL, the record will show two paths.

OPERATING MODES
       You can choose whether you want to trust	the index file entirely	(using
       the --cached flag) or ask the diff logic	to show	any files that don't
       match the stat state as being "tentatively changed". Both of these
       operations are very useful indeed.

CACHED MODE
       If --cached is specified, it allows you to ask:

	   show	me the differences between HEAD	and the	current	index
	   contents (the ones I'd write	using 'git write-tree')

       For example, let's say that you have worked on your working directory,
       updated some files in the index and are ready to	commit.	You want to
       see exactly what	you are	going to commit, without having	to write a new
       tree object and compare it that way, and	to do that, you	just do

	   git diff-index --cached HEAD

       Example:	let's say I had	renamed	commit.c to git-commit.c, and I	had
       done an update-index to make that effective in the index	file. git
       diff-files wouldn't show	anything at all, since the index file matches
       my working directory. But doing a git diff-index	does:

	   torvalds@ppc970:~/git> git diff-index --cached HEAD
	   -100644 blob	   4161aecc6700a2eb579e842af0b7f22b98443f74	   commit.c
	   +100644 blob	   4161aecc6700a2eb579e842af0b7f22b98443f74	   git-commit.c

       You can see easily that the above is a rename.

       In fact,	git diff-index --cached	should always be entirely equivalent
       to actually doing a git write-tree and comparing	that. Except this one
       is much nicer for the case where	you just want to check where you are.

       So doing	a git diff-index --cached is basically very useful when	you
       are asking yourself "what have I	already	marked for being committed,
       and what's the difference to a previous tree".

NON-CACHED MODE
       The "non-cached"	mode takes a different approach, and is	potentially
       the more	useful of the two in that what it does can't be	emulated with
       a git write-tree	+ git diff-tree. Thus that's the default mode. The
       non-cached version asks the question:

	   show	me the differences between HEAD	and the	currently checked out
	   tree	- index	contents _and_ files that aren't up-to-date

       which is	obviously a very useful	question too, since that tells you
       what you	could commit. Again, the output	matches	the git	diff-tree -r
       output to a tee,	but with a twist.

       The twist is that if some file doesn't match the	index, we don't	have a
       backing store thing for it, and we use the magic	"all-zero" sha1	to
       show that. So let's say that you	have edited kernel/sched.c, but	have
       not actually done a git update-index on it yet -	there is no "object"
       associated with the new state, and you get:

	   torvalds@ppc970:~/v2.6/linux> git diff-index	--abbrev HEAD
	   :100644 100664 7476bb... 000000...	   kernel/sched.c

       i.e., it	shows that the tree has	changed, and that kernel/sched.c has
       is not up-to-date and may contain new stuff. The	all-zero sha1 means
       that to get the real diff, you need to look at the object in the
       working directory directly rather than do an object-to-object diff.

	   Note
	   As with other commands of this type,	git diff-index does not
	   actually look at the	contents of the	file at	all. So	maybe
	   kernel/sched.c hasn't actually changed, and it's just that you
	   touched it. In either case, it's a note that	you need to git
	   update-index	it to make the index be	in sync.

	   Note
	   You can have	a mixture of files show	up as "has been	updated" and
	   "is still dirty in the working directory" together. You can always
	   tell	which file is in which state, since the	"has been updated"
	   ones	show a valid sha1, and the "not	in sync	with the index"	ones
	   will	always have the	special	all-zero sha1.

GIT
       Part of the git(1) suite

Git 2.13.2			  06/24/2017		     GIT-DIFF-INDEX(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | RAW OUTPUT FORMAT | DIFF FORMAT FOR MERGES | GENERATING PATCHES WITH -P | COMBINED DIFF FORMAT | OTHER DIFF FORMATS | OPERATING MODES | CACHED MODE | NON-CACHED MODE | GIT

Want to link to this manual page? Use this URL:
<https://www.freebsd.org/cgi/man.cgi?query=git-diff-index&sektion=1&manpath=FreeBSD+12.0-RELEASE+and+Ports>

home | help