From Linux Man Pages
git-diff-files - Compares files in the working tree and the index
git-diff-files [-q] [-0|-1|-2|-3|-c|--cc] [<common diff options>] [<path>...]
DESCRIPTION
Compares the files in the working tree and the index. When paths are specified, compares only those named paths.
Otherwise all entries in the index are compared. The output format is the same as "git-diff-index" and
"git-diff-tree".
OPTIONS
-p
Generate patch (see section on generating patches)
-u
Synonym for "-p".
--raw
Generate the raw format.
--patch-with-raw
Synonym for "-p --raw".
--stat[=width[,name-width]]
Generate a diffstat. You can override the default output width for 80-column terminal by "--stat=width". The
width of the filename part can be controlled by giving another width to it separated by a comma.
--summary
Output a condensed summary of extended header information such as creations, renames and mode changes.
--patch-with-stat
Synonym for "-p --stat".
-z
\0 line termination on output
--name-only
Show only names of changed files.
--name-status
Show only names and status of changed files.
--color
Show colored diff.
--no-color
Turn off colored diff, even when the configuration file gives the default to color output.
--color-words
Show colored word diff, i.e. color words which have changed.
--no-renames
Turn off rename detection, even when the configuration file gives the default to do so.
--full-index
Instead of the first handful characters, show full object name of pre- and post-image blob on the "index"
line when generating a patch format output.
--binary
In addition to --full-index, output "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 handful hexdigits prefix. This is independent of --full-index option above, which controls
the diff-patch output format. Non default number of digits can be specified with --abbrev=<n>.
-B
Break complete rewrite changes into pairs of delete and create.
-M
Detect renames.
-C
Detect copies as well as renames.
--diff-filter=[ACDMRTUXB*]
Select only files that are Added (A), Copied (C), Deleted (D), Modified (M), Renamed (R), have their type
(mode) changed (T), are Unmerged (U), are Unknown (X), or have had their pairing Broken (B). Any combination
of the filter characters may 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.
--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.
-l<num>
-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.
-S<string>
Look for differences that contain the change in <string>.
--pickaxe-all
When -S finds a change, show all the changes in that changeset, not just the files that contain the change in
<string>.
--pickaxe-regex
Make the <string> not a plain string but an extended POSIX regex to match.
-O<orderfile>
Output the patch in the order specified in the <orderfile>, which has one shell glob pattern per line.
-R
Swap two inputs; that is, show differences from index or on-disk file to tree contents.
--text
Treat all files as text.
-a
Shorthand for "--text".
For more detailed explanation on these common options, see also diffcore documentation[1].
-1 -2 -3 or --base --ours --theirs, and -0
Diff against the "base" version, "our branch" or "their branch" respectively. With these options, diffs for
merged entries are not shown.
The default is to diff against our branch (-2) and the cleanly resolved paths. The option -0 can be given to
omit diff output for unmerged entries and just show "Unmerged".
-c,--cc
This compares stage 2 (our branch), stage 3 (their branch) and the working tree file and outputs a combined
diff, similar to the way diff-tree shows a merge commit with these flags.
-q
Remain silent even on nonexistent files
OUTPUT FORMAT
The output format from "git-diff-index", "git-diff-tree" and "git-diff-files" 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.
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. <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
When -z option is not used, TAB, LF, and backslash characters in pathnames are represented as \t, 0 and \\,
respectively.
GENERATING PATCHES WITH -P
When "git-diff-index", "git-diff-tree", or "git-diff-files" are run with a -p option, they do not produce the
output described above; instead they produce a patch file.
The patch generation can be customized at two levels.
1. When the environment variable GIT_EXTERNAL_DIFF is not set, these commands internally invoke "diff" like
this:
diff -L a/<path> -L b/<path> -pu <old> <new>
For added files, /dev/null is used for <old>. For removed files, /dev/null is used for <new>
The "diff" formatting options can be customized via the environment variable GIT_DIFF_OPTS. For example, if you
prefer context diff:
GIT_DIFF_OPTS=-c git-diff-index -p HEAD
2. When the environment variable GIT_EXTERNAL_DIFF is set, the program named by it is called, instead of the
diff invocation described above.
For a path that is added, removed, or modified, GIT_EXTERNAL_DIFF is called with 7 parameters:
path old-file old-hex old-mode new-file new-hex new-mode
where:
tab(:); l l l l l l. T{ <old|new>-file T}:T{ are files GIT_EXTERNAL_DIFF can use to read the contents of
<old|new>, T} T{ <old|new>-hex T}:T{ are the 40-hexdigit SHA1 hashes, T} T{ <old|new>-mode T}:T{ are the octal
representation of the file modes. T}
The file parameters can point at the user's working file (e.g. new-file in "git-diff-files"), /dev/null (e.g.
old-file when a new file is added), or a temporary file (e.g. old-file in the index). GIT_EXTERNAL_DIFF should
not worry about unlinking the temporary file --- it is removed when GIT_EXTERNAL_DIFF exits. For a path that is
unmerged, GIT_EXTERNAL_DIFF is called with 1 parameter, <path>.
GIT SPECIFIC EXTENSION TO DIFF FORMAT
What -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 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>
3. TAB, LF, double quote and backslash characters in pathnames are represented as \t, 0 \" and \\, respectively.
If there is need for such substitution then the whole pathname is put in double quotes.
COMBINED DIFF FORMAT
git-diff-tree and git-diff-files can take -c or --cc option to produce combined diff, which 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 --c 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 diferent 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 last file, 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 nor file2). Also two
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").
DOCUMENTATION
Documentation by David Greaves, Junio C Hamano and the git-list <git@vger.kernel.org>.
GIT
Part of the git(7) suite
REFERENCES
1. diffcore documentation
diffcore.html
CATEGORY