(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) status, followed by optional "score" number.
- (10) a tab or a NUL when '-z' option is used.
- (11) path for "src"
- (12) a tab or a NUL when '-z' option is used; only exists for C or R.
- (13) path for "dst"; only exists for C or R.
- (14) an LF or a NUL when '-z' option is used, to terminate the record.
+ (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 new is a file on the filesystem
and it is out of sync with the cache. Example:
--------------------------
When "git-diff-cache", "git-diff-tree", or "git-diff-files" are run
-with a '-p' option, they do not produce the output described above
+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. This
1. When the environment variable 'GIT_EXTERNAL_DIFF' is not set,
these commands internally invoke "diff" like this:
- diff -L a/<path> -L
a/<path> -pu <old> <new>
+ 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>
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 preceeded 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/ filename.
+
+ When rename/copy is involved, file1 and file2 shows 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 extended header lines that are one or
+ more of:
+
+ 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>