You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
195 lines
6.4 KiB
195 lines
6.4 KiB
git-blame(1) |
|
============ |
|
|
|
NAME |
|
---- |
|
git-blame - Show what revision and author last modified each line of a file |
|
|
|
SYNOPSIS |
|
-------- |
|
[verse] |
|
'git-blame' [-c] [-b] [-l] [--root] [-t] [-f] [-n] [-s] [-p] [-w] [--incremental] [-L n,m] |
|
[-S <revs-file>] [-M] [-C] [-C] [--since=<date>] |
|
[<rev> | --contents <file>] [--] <file> |
|
|
|
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 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: |
|
|
|
----------------------------------------------------------------------------- |
|
$ git log --pretty=oneline -S'blame_usage' |
|
5040f17eba15504bad66b14a645bddd9b015ebb7 blame -S <ancestry-file> |
|
ea4c7f9bf69e781dd0cd88d2bccb2bf5cc15c9a7 git-blame: Make the output |
|
----------------------------------------------------------------------------- |
|
|
|
OPTIONS |
|
------- |
|
include::blame-options.txt[] |
|
|
|
-c:: |
|
Use the same output mode as gitlink:git-annotate[1] (Default: off). |
|
|
|
--score-debug:: |
|
Include debugging information related to the movement of |
|
lines between files (see `-C`) and lines moved within a |
|
file (see `-M`). The first number listed is the score. |
|
This is the number of alphanumeric characters detected |
|
to be moved between or within files. This must be above |
|
a certain threshold for git-blame to consider those lines |
|
of code to have been moved. |
|
|
|
-f, --show-name:: |
|
Show filename in the original commit. By default |
|
filename is shown if there is any line that came from a |
|
file with different name, due to rename detection. |
|
|
|
-n, --show-number:: |
|
Show line number in the original commit (Default: off). |
|
|
|
-s:: |
|
Suppress author name and timestamp from the output. |
|
|
|
-w:: |
|
Ignore whitespace when comparing parent's version and |
|
child's to find where the lines came from. |
|
|
|
|
|
THE PORCELAIN FORMAT |
|
-------------------- |
|
|
|
In this format, each line is output after a header; the |
|
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; |
|
- the line number of the line in the final file; |
|
- on a line that starts a group of line from a different |
|
commit than the previous one, the number of lines in this |
|
group. On subsequent lines this field is absent. |
|
|
|
This header line is followed by the following information |
|
at least once for each commit: |
|
|
|
- author name ("author"), email ("author-mail"), time |
|
("author-time"), and timezone ("author-tz"); similarly |
|
for committer. |
|
- filename in the commit the line is attributed to. |
|
- the first line of the commit log message ("summary"). |
|
|
|
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> <sourceline> <resultline> <num_lines> |
|
+ |
|
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" <whitespace-quoted-filename-goes-here> |
|
+ |
|
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 ("<sha1>" 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 Junio C Hamano <junkio@cox.net> |
|
|
|
GIT |
|
--- |
|
Part of the gitlink:git[7] suite
|
|
|