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GIT-DIFF-INDEX(1) Git Manual GIT-DIFF-INDEX(1)
git-diff-index - Compare a tree to the working tree or index
git diff-index [-m] [--cached] [--merge-base] [<common-diff-options>] <tree-ish> [<path>...]
Compare 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, compare only paths matching those patterns. Otherwise
all tracked files are compared.
-p, -u, --patch
Generate patch (see the section called “GENERATING PATCH TEXT
WITH -P”).
-s, --no-patch
Suppress all output from the diff machinery. Useful for
commands like git show that show the patch by default to
squelch their output, or to cancel the effect of options like
--patch, --stat earlier on the command line in an alias.
-U<n>, --unified=<n>
Generate diffs with <n> lines of context instead of the usual
three. Implies --patch.
--output=<file>
Output to a specific file instead of stdout.
--output-indicator-new=<char>, --output-indicator-old=<char>,
--output-indicator-context=<char>
Specify the character used to indicate new, old or context
lines in the generated patch. Normally they are +, - and ' '
respectively.
--raw
Generate the diff in raw format. This is the default.
--patch-with-raw
Synonym for -p --raw.
--indent-heuristic
Enable the heuristic that shifts diff hunk boundaries to make
patches easier to read. This is the default.
--no-indent-heuristic
Disable the indent heuristic.
--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.
--anchored=<text>
Generate a diff using the "anchored diff" algorithm.
This option may be specified more than once.
If a line exists in both the source and destination, exists
only once, and starts with this text, this algorithm attempts
to prevent it from appearing as a deletion or addition in the
output. It uses the "patience diff" algorithm internally.
--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 the 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 or by setting
diff.statNameWidth=<width>. The width of the graph part can
be limited by using --stat-graph-width=<width> or by setting
diff.statGraphWidth=<width>. Using --stat or
--stat-graph-width affects all commands generating a stat
graph, while setting diff.statNameWidth or
diff.statGraphWidth 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>.
--compact-summary
Output a condensed summary of extended header information
such as file creations or deletions ("new" or "gone",
optionally "+l" if it’s a symlink) and mode changes ("+x" or
"-x" for adding or removing executable bit respectively) in
diffstat. The information is put between the filename part
and the graph part. Implies --stat.
--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.
-X[<param1,param2,...>], --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.
--cumulative
Synonym for --dirstat=cumulative
--dirstat-by-file[=<param1,param2>...]
Synonym for --dirstat=files,<param1>,<param2>...
--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 the name of each changed file in the post-image
tree. The file names are often encoded in UTF-8. For more
information see the discussion about encoding in the
git-log(1) manual page.
--name-status
Show only the name(s) and status of each changed file. See
the description of the --diff-filter option on what the
status letters mean. Just like --name-only the file names are
often encoded in UTF-8.
--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.
--color-moved[=<mode>]
Moved lines of code are colored differently. The <mode>
defaults to no if the option is not given and to zebra if the
option with no mode is given. The mode must be one of:
no
Moved lines are not highlighted.
default
Is a synonym for zebra. This may change to a more
sensible mode in the future.
plain
Any line that is added in one location and was removed in
another location will be colored with
color.diff.newMoved. Similarly color.diff.oldMoved will
be used for removed lines that are added somewhere else
in the diff. This mode picks up any moved line, but it is
not very useful in a review to determine if a block of
code was moved without permutation.
blocks
Blocks of moved text of at least 20 alphanumeric
characters are detected greedily. The detected blocks are
painted using either the color.diff.{old,new}Moved color.
Adjacent blocks cannot be told apart.
zebra
Blocks of moved text are detected as in blocks mode. The
blocks are painted using either the
color.diff.{old,new}Moved color or
color.diff.{old,new}MovedAlternative. The change between
the two colors indicates that a new block was detected.
dimmed-zebra
Similar to zebra, but additional dimming of uninteresting
parts of moved code is performed. The bordering lines of
two adjacent blocks are considered interesting, the rest
is uninteresting. dimmed_zebra is a deprecated synonym.
--no-color-moved
Turn off move detection. This can be used to override
configuration settings. It is the same as --color-moved=no.
--color-moved-ws=<modes>
This configures how whitespace is ignored when performing the
move detection for --color-moved. These modes can be given as
a comma separated list:
no
Do not ignore whitespace when performing move detection.
ignore-space-at-eol
Ignore changes in whitespace at EOL.
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.
ignore-all-space
Ignore whitespace when comparing lines. This ignores
differences even if one line has whitespace where the
other line has none.
allow-indentation-change
Initially ignore any whitespace in the move detection,
then group the moved code blocks only into a block if the
change in whitespace is the same per line. This is
incompatible with the other modes.
--no-color-moved-ws
Do not ignore whitespace when performing move detection. This
can be used to override configuration settings. It is the
same as --color-moved-ws=no.
--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.
--[no-]rename-empty
Whether to use empty blobs as rename source.
--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 consist solely 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 in the context, old or new lines
of the diff. Multiple values are separated by comma, none
resets previous values, default reset the list to new and all
is a shorthand for old,new,context. When this option is not
given, and the configuration variable diff.wsErrorHighlight
is not set, only whitespace errors in new lines are
highlighted. The whitespace errors are colored with
color.diff.whitespace.
--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. Implies --patch.
--abbrev[=<n>]
Instead of showing the full 40-byte hexadecimal object name
in diff-raw format output and diff-tree header lines, show
the shortest prefix that is at least <n> hexdigits long that
uniquely refers the object. In diff-patch output format,
--full-index takes higher precedence, i.e. if --full-index is
specified, full blob names will be shown regardless of
--abbrev. 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 lacks 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 involve some preliminary steps that can
detect subsets of renames/copies cheaply, followed by an
exhaustive fallback portion that compares all remaining
unpaired destinations to all relevant sources. (For renames,
only remaining unpaired sources are relevant; for copies, all
original sources are relevant.) For N sources and
destinations, this exhaustive check is O(N^2). This option
prevents the exhaustive portion of rename/copy detection from
running if the number of source/destination files involved
exceeds the specified number. Defaults to diff.renameLimit.
Note that a value of 0 is treated as unlimited.
--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.
Note that not all diffs can feature all types. For instance,
copied and renamed entries cannot appear if detection for
those types is disabled.
-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.
Binary files are searched as well.
-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 frotz(nitfol, two->ptr, 1, 0);
...
- hit = frotz(nitfol, mf2.ptr, 1, 0);
While git log -G"frotz\(nitfol" will show this commit, git
log -S"frotz\(nitfol" --pickaxe-regex will not (because the
number of occurrences of that string did not change).
Unless --text is supplied patches of binary files without a
textconv filter will be ignored.
See the pickaxe entry in gitdiffcore(7) for more information.
--find-object=<object-id>
Look for differences that change the number of occurrences of
the specified object. Similar to -S, just the argument is
different in that it doesn’t search for a specific string but
for a specific object id.
The object can be a blob or a submodule commit. It implies
the -t option in git-log to also find trees.
--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:
• Blank lines are ignored, so they can be used as
separators for readability.
• 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.
• Each other line contains a single pattern.
Patterns have the same syntax and semantics as patterns used
for fnmatch(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".
--skip-to=<file>, --rotate-to=<file>
Discard the files before the named <file> from the output
(i.e. skip to), or move them to the end of the output (i.e.
rotate to). These options were invented primarily for the use
of the git difftool command, and may not be very useful
otherwise.
-R
Swap two inputs; that is, show differences from index or
on-disk file to tree contents.
--relative[=<path>], --no-relative
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. --no-relative can be used to
countermand both diff.relative config option and previous
--relative.
-a, --text
Treat all files as text.
--ignore-cr-at-eol
Ignore carriage-return at the end of line when doing a
comparison.
--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.
-I<regex>, --ignore-matching-lines=<regex>
Ignore changes whose all lines match <regex>. This option may
be specified more than once.
--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 function as context lines for each change. The
function names are determined in the same way as git diff
works out patch hunk headers (see Defining a custom
hunk-header in gitattributes(5)).
--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.
--default-prefix
Use the default source and destination prefixes ("a/" and
"b/"). This overrides configuration variables such as
diff.noprefix, diff.srcPrefix, diff.dstPrefix, and
diff.mnemonicPrefix (see git-config(1)).
--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.
--merge-base
Instead of comparing <tree-ish> directly, use the merge base
between <tree-ish> and HEAD instead. <tree-ish> must be a
commit.
-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.
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 deletion, unmerged or "work tree out
of sync with the index".
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:
• A: addition of a file
• C: copy of a file into a new one
• D: deletion of a file
• M: modification of the contents or mode of a file
• R: renaming of a file
• T: change in the type of the file (regular file, symbolic
link or submodule)
• U: file is unmerged (you must complete the merge before it
can be committed)
• 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.
The sha1 for "dst" is shown as all 0’s if a file on the
filesystem is out of sync with the index.
Example:
:100644 100644 5be4a4a 0000000 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.
"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. tab-separated pathname(s) of the file
For -c and --cc, only the destination or final path is shown even
if the file was renamed on any side of history. With
--combined-all-paths, the name of the path in each parent is
shown followed by the name of the path in the merge commit.
Examples for -c and --cc without --combined-all-paths:
::100644 100644 100644 fabadb8 cc95eb0 4866510 MM desc.c
::100755 100755 100755 52b7a2d 6d1ac04 d2ac7d7 RM bar.sh
::100644 100644 100644 e07d6c5 9042e82 ee91881 RR phooey.c
Examples when --combined-all-paths added to either -c or --cc:
::100644 100644 100644 fabadb8 cc95eb0 4866510 MM desc.c desc.c desc.c
::100755 100755 100755 52b7a2d 6d1ac04 d2ac7d7 RM foo.sh bar.sh bar.sh
::100644 100644 100644 e07d6c5 9042e82 ee91881 RR fooey.c fuey.c phooey.c
Note that combined diff lists only files which were modified from
all parents.
Running git-diff(1), git-log(1), git-show(1), git-diff-index(1),
git-diff-tree(1), or git-diff-files(1) with the -p option
produces patch text. You can customize the creation of patch text
via the GIT_EXTERNAL_DIFF and the GIT_DIFF_OPTS environment
variables (see git(1)), and the diff attribute (see
gitattributes(5)).
What the -p option produces is slightly different from the
traditional diff format:
1. It is preceded by 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 a 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 the 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 blob object names 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
5. Hunk headers mention the name of the function to which the
hunk applies. See "Defining a custom hunk-header" in
gitattributes(5) for details of how to tailor this to
specific languages.
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 suitable --diff-merges option to any of
these commands to force generation of diffs in a specific format.
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 by a "git diff" header, that looks like this
(when the -c option is used):
diff --combined file
or like this (when the --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 content movement
(renames and copying detection) are designed to work with the
diff of two <tree-ish> and are not used by combined diff
format.
3. It is followed by a two-line from-file/to-file header:
--- a/file
+++ b/file
Similar to the two-line header for the traditional unified
diff format, /dev/null is used to signal created or deleted
files.
However, if the --combined-all-paths option is provided,
instead of a two-line from-file/to-file, you get an N+1 line
from-file/to-file header, where N is the number of parents in
the merge commit:
--- a/file
--- a/file
--- a/file
+++ b/file
This extended format can be useful if rename or copy
detection is active, to allow you to see the original name of
the file in different parents.
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 to be applied. 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").
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.
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.
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 000000 4161aecc6700a2eb579e842af0b7f22b98443f74 0000000000000000000000000000000000000000 D commit.c
:000000 100644 0000000000000000000000000000000000000000 4161aecc6700a2eb579e842af0b7f22b98443f74 A 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".
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 100644 7476bb5ba 000000000 M kernel/sched.c
i.e., it shows that the tree has changed, and that kernel/sched.c
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.
Part of the git(1) suite
This page is part of the git (Git distributed version control
system) project. Information about the project can be found at
⟨http://git-scm.com/⟩. If you have a bug report for this manual
page, see ⟨http://git-scm.com/community⟩. This page was obtained
from the project's upstream Git repository
⟨https://github.com/git/git.git⟩ on 2024-06-14. (At that time,
the date of the most recent commit that was found in the
repository was 2024-06-12.) If you discover any rendering
problems in this HTML version of the page, or you believe there
is a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
[email protected]
Git 2.45.2.492.gd63586 2024-06-12 GIT-DIFF-INDEX(1)
Pages that refer to this page: git(1), git-diff(1), git-diff-files(1), git-diff-index(1), git-diff-tree(1), git-log(1), git-show(1), gitdiffcore(7)
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