X-Git-Url: https://git.verplant.org/?a=blobdiff_plain;f=Documentation%2Fdiff-format.txt;h=6e9fa8cdb70faead4649f71aea4fff8f50d17271;hb=deca7e8c591608c9ffd0bf0aaf10b379da9f6d6e;hp=7e9a515ad74b16c3f82eba71a9503c6696c77503;hpb=81e50eabf06dd68e8e62a9b697eaf60904c58b22;p=git.git

diff --git a/Documentation/diff-format.txt b/Documentation/diff-format.txt
index 7e9a515a..6e9fa8cd 100644
--- a/Documentation/diff-format.txt
+++ b/Documentation/diff-format.txt
@@ -1,13 +1,13 @@
-The output format from "git-diff-cache", "git-diff-tree" and
-"git-diff-files" is very similar.
+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 are
 compared are different:
 
-git-diff-cache <tree-ish>::
+git-diff-index <tree-ish>::
         compares the <tree-ish> and the files on the filesystem.
 
-git-diff-cache --cached <tree-ish>::
+git-diff-index --cached <tree-ish>::
         compares the <tree-ish> and the cache.
 
 git-diff-tree [-r] <tree-ish-1> <tree-ish-2> [<pattern>...]::
@@ -19,43 +19,55 @@ git-diff-files [<pattern>...]::
 
 An output line is formatted this way:
 
-  ':' <mode> ' ' <mode> ' ' <sha1> ' ' <sha1> I <path> I <path> L
-
-By default, I and L are '\t' and '\n' respectively.  When '-z'
-flag is in effect, both I and L are '\0'.
-
-In each <mode>, <sha1> and <path> pair, left hand side describes
-the left hand side of what is being compared (<tree-ish> in
-git-diff-cache, <tree-ish-1> in git-diff-tree, cache contents in
-git-diff-files).  Non-existence is shown by having 000000 in the
-<mode> column.  That is, 000000 appears as the first <mode> for
-newly created files, and as the second <mode> for deleted files.
-
-Usually two <path> are the same.  When rename/copy detection is
-used, however, an "create" and another "delete" records can be
-merged into a single record that has two <path>, old name and
-new name.
+------------------------------------------------
+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:
+
+. a colon.
+. mode for "src"; 000000 if creation or unmerged.
+. a space.
+. mode for "dst"; 000000 if deletion or unmerged.
+. a space.
+. sha1 for "src"; 0\{40\} if creation or unmerged.
+. a space.
+. sha1 for "dst"; 0\{40\} if creation, unmerged or "look at work tree".
+. a space.
+. status, followed by optional "score" number.
+. a tab or a NUL when '-z' option is used.
+. path for "src"
+. a tab or a NUL when '-z' option is used; only exists for C or R.
+. path for "dst"; only exists for C or R.
+. 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:
+and it is out of sync with the cache.
 
-  :100644 100644 5be4a4...... 000000......    file.c    file.c
+Example:
 
+------------------------------------------------
+:100644 100644 5be4a4...... 000000...... M file.c
+------------------------------------------------
 
 Generating patches with -p
 --------------------------
 
-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
+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.  This
-customization also applies to "git-diff-helper".
+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 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>
@@ -64,7 +76,7 @@ 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-cache -p $(cat .git/HEAD)
+      GIT_DIFF_OPTS=-c git-diff-index -p $(cat .git/HEAD)
 
 
 2. When the environment variable 'GIT_EXTERNAL_DIFF' is set, the
@@ -92,3 +104,37 @@ 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 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/` filenames.
++
+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>