X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=Documentation%2Fgit-blame.txt;h=5c9888d0143ec8e6c8f7c6782139cde38a25ff17;hb=55a643ed1b9b9af4d3bd9dc934dfccd142d1c632;hp=9891c1d3779185c200345c0e6d92763aa155a169;hpb=66d0ff1bd35530f84c2b73e2b0e367637805217a;p=git.git diff --git a/Documentation/git-blame.txt b/Documentation/git-blame.txt index 9891c1d37..5c9888d01 100644 --- a/Documentation/git-blame.txt +++ b/Documentation/git-blame.txt @@ -7,7 +7,9 @@ git-blame - Show what revision and author last modified each line of a file SYNOPSIS -------- -'git-blame' [-c] [-l] [-t] [-f] [-n] [-p] [-S ] [--] [] +[verse] +'git-blame' [-c] [-l] [-t] [-f] [-n] [-p] [--incremental] [-L n,m] [-S ] + [-M] [-C] [-C] [--since=] [ | --contents ] [--] DESCRIPTION ----------- @@ -15,12 +17,14 @@ DESCRIPTION Annotates each line in the given file with information from the revision which last modified the line. Optionally, start annotating from the given revision. +Also it can limit the range of lines annotated. + This report doesn't tell you anything about lines which have been deleted or replaced; you need to use a tool such as gitlink:git-diff[1] or the "pickaxe" interface briefly mentioned in the following paragraph. Apart from supporting file annotation, git also supports searching the -development history for when a code snippet occured in a change. This makes it +development history for when a code snippet occurred in a change. This makes it possible to track when a code snippet was added to a file, moved or copied between files, and eventually deleted or replaced. It works by searching for a text string in the diff. A small example: @@ -36,6 +40,9 @@ OPTIONS -c, --compatibility:: Use the same output mode as gitlink:git-annotate[1] (Default: off). +-L n,m:: + Annotate only the specified line range (lines count from 1). + -l, --long:: Show long rev (Default: off). @@ -56,6 +63,35 @@ OPTIONS -p, --porcelain:: Show in a format designed for machine consumption. +--incremental:: + Show the result incrementally in a format designed for + machine consumption. + +--contents :: + When is not specified, the command annotates the + changes starting backwards from the working tree copy. + This flag makes the command pretend as if the working + tree copy has the contents of he named file (specify + `-` to make the command read from the standard input). + +-M:: + Detect moving lines in the file as well. When a commit + moves a block of lines in a file (e.g. the original file + has A and then B, and the commit changes it to B and + then A), traditional 'blame' algorithm typically blames + the lines that were moved up (i.e. B) to the parent and + assigns blame to the lines that were moved down (i.e. A) + to the child commit. With this option, both groups of + lines are blamed on the parent. + +-C:: + In addition to `-M`, detect lines copied from other + files that were modified in the same commit. This is + useful when you reorganize your program and move code + around across files. When this option is given twice, + the command looks for copies from all other files in the + parent for the commit that creates the file in addition. + -h, --help:: Show help message. @@ -64,7 +100,7 @@ THE PORCELAIN FORMAT -------------------- In this format, each line is output after a header; the -header at the minumum has the first line which has: +header at the minimum has the first line which has: - 40-byte SHA-1 of the commit the line is attributed to; - the line number of the line in the original file; @@ -86,13 +122,101 @@ The contents of the actual line is output after the above header, prefixed by a TAB. This is to allow adding more header elements later. + +SPECIFYING RANGES +----------------- + +Unlike `git-blame` and `git-annotate` in older git, the extent +of annotation can be limited to both line ranges and revision +ranges. When you are interested in finding the origin for +ll. 40-60 for file `foo`, you can use `-L` option like these +(they mean the same thing -- both ask for 21 lines starting at +line 40): + + git blame -L 40,60 foo + git blame -L 40,+21 foo + +Also you can use regular expression to specify the line range. + + git blame -L '/^sub hello {/,/^}$/' foo + +would limit the annotation to the body of `hello` subroutine. + +When you are not interested in changes older than the version +v2.6.18, or changes older than 3 weeks, you can use revision +range specifiers similar to `git-rev-list`: + + git blame v2.6.18.. -- foo + git blame --since=3.weeks -- foo + +When revision range specifiers are used to limit the annotation, +lines that have not changed since the range boundary (either the +commit v2.6.18 or the most recent commit that is more than 3 +weeks old in the above example) are blamed for that range +boundary commit. + +A particularly useful way is to see if an added file have lines +created by copy-and-paste from existing files. Sometimes this +indicates that the developer was being sloppy and did not +refactor the code properly. You can first find the commit that +introduced the file with: + + git log --diff-filter=A --pretty=short -- foo + +and then annotate the change between the commit and its +parents, using `commit{caret}!` notation: + + git blame -C -C -f $commit^! -- foo + + +INCREMENTAL OUTPUT +------------------ + +When called with `--incremental` option, the command outputs the +result as it is built. The output generally will talk about +lines touched by more recent commits first (i.e. the lines will +be annotated out of order) and is meant to be used by +interactive viewers. + +The output format is similar to the Porcelain format, but it +does not contain the actual lines from the file that is being +annotated. + +. Each blame entry always starts with a line of: + + <40-byte hex sha1> ++ +Line numbers count from 1. + +. The first time that commit shows up in the stream, it has various + other information about it printed out with a one-word tag at the + beginning of each line about that "extended commit info" (author, + email, committer, dates, summary etc). + +. Unlike Porcelain format, the filename information is always + given and terminates the entry: + + "filename" ++ +and thus it's really quite easy to parse for some line- and word-oriented +parser (which should be quite natural for most scripting languages). ++ +[NOTE] +For people who do parsing: to make it more robust, just ignore any +lines in between the first and last one ("" and "filename" lines) +where you don't recognize the tag-words (or care about that particular +one) at the beginning of the "extended information" lines. That way, if +there is ever added information (like the commit encoding or extended +commit commentary), a blame viewer won't ever care. + + SEE ALSO -------- gitlink:git-annotate[1] AUTHOR ------ -Written by Fredrik Kuivinen . +Written by Junio C Hamano GIT ---