X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=Documentation%2Fdiff-format.txt;h=617d8f526f914360c612d2e2822f1c883c9f5115;hb=HEAD;hp=9298d79e51bf87ccff66357227c7df4db4c820c4;hpb=3f81fc82743ccd4fd7157f1f1db41605eb018fb9;p=git.git diff --git a/Documentation/diff-format.txt b/Documentation/diff-format.txt index 9298d79e..617d8f52 100644 --- a/Documentation/diff-format.txt +++ b/Documentation/diff-format.txt @@ -1,63 +1,73 @@ -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: +These commands all compare two sets of things; what is +compared differs: -git-diff-cache :: +git-diff-index :: compares the and the files on the filesystem. -git-diff-cache --cached :: - compares the and the cache. +git-diff-index --cached :: + compares the and the index. git-diff-tree [-r] [...]:: compares the trees named by the two arguments. git-diff-files [...]:: - compares the cache and the files on the filesystem. + 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... N file4 +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. - - is shown as all 0's if new is a file on the filesystem -and it is out of sync with the cache. Example: - - :100644 100644 5be4a4...... 000000...... M file.c +. 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. + + 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`, `\n`, and `\\`, +respectively. + Generating patches with -p -------------------------- -When "git-diff-cache", "git-diff-tree", or "git-diff-files" are run +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: @@ -71,7 +81,7 @@ 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 HEAD 2. When the environment variable 'GIT_EXTERNAL_DIFF' is set, the @@ -86,7 +96,7 @@ For a path that is added, removed, or modified, where: -file:: are files GIT_EXTERNAL_DIFF can use to read the - contents of , + contents of , -hex:: are the 40-hexdigit SHA1 hashes, -mode:: are the octal representation of the file modes. @@ -94,34 +104,33 @@ where: 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 -cache). 'GIT_EXTERNAL_DIFF' should not worry about unlinking 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, . -Git specific extension to diff format +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 +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. - 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: +2. It is followed by one or more extended header lines: old mode new mode @@ -133,3 +142,56 @@ traditional diff format. rename to similarity index dissimilarity index + index .. + +3. TAB, LF, and backslash characters in pathnames are + represented as `\t`, `\n`, and `\\`, respectively. + + +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 +@@@ +98,7 @@@ + 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; +------------ + +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 last file. A `+` character +in the column N means that the line appears in the last file, +and fileN does not have that line. + +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"). +