NAME
git-blame - Show what revision and author last modified each line of a fileSYNOPSIS
git blame [-c] [-b] [-l] [--root] [-t] [-f] [-n] [-s] [-e] [-p] [-w] [--incremental] [-L <range>] [-S <revs-file>] [-M] [-C] [-C] [-C] [--since=<date>] [--ignore-rev <rev>] [--ignore-revs-file <file>] [--color-lines] [--color-by-age] [--progress] [--abbrev=<n>] [<rev> | --contents <file> | --reverse <rev>..<rev>] [--] <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.$ git log --pretty=oneline -S'blame_usage' 5040f17eba15504bad66b14a645bddd9b015ebb7 blame -S <ancestry-file> ea4c7f9bf69e781dd0cd88d2bccb2bf5cc15c9a7 git-blame: Make the output
OPTIONS
-bShow blank SHA-1 for boundary commits. This
can also be controlled via the blame.blankBoundary config option.
--root
Do not treat root commits as boundaries. This
can also be controlled via the blame.showRoot config option.
--show-stats
Include additional statistics at the end of
blame output.
-L <start>,<end>, -L :<funcname>
Annotate only the line range given by
<start>,<end>, or by the function name regex
<funcname>. May be specified multiple times. Overlapping ranges
are allowed.
<start> and <end> are optional. -L
<start> or -L <start>, spans from <start>
to end of file. -L ,<end> spans from start of file to
<end>.
<start> and <end> can take one of these forms:
If :<funcname> is given in place of <start> and
<end>, it is a regular expression that denotes the range from the
first funcname line that matches <funcname>, up to the next
funcname line. :<funcname> searches from the end of the previous
-L range, if any, otherwise from the start of file.
^:<funcname> searches from the start of file. The function names
are determined in the same way as git diff works out patch hunk headers
(see Defining a custom hunk-header in gitattributes(5)).
-l
•number
If <start> or <end> is a number, it specifies an
absolute line number (lines count from 1).
•/regex/
This form will use the first line matching the given POSIX regex. If
<start> is a regex, it will search from the end of the previous
-L range, if any, otherwise from the start of file. If
<start> is ^/regex/, it will search from the start of
file. If <end> is a regex, it will search starting at the line
given by <start>.
•+offset or -offset
This is only valid for <end> and will specify a number of lines
before or after the line given by <start>.
Show long rev (Default: off).
-t
Show raw timestamp (Default: off).
-S <revs-file>
Use revisions from revs-file instead of
calling git-rev-list(1).
--reverse <rev>..<rev>
Walk history forward instead of backward.
Instead of showing the revision in which a line appeared, this shows the last
revision in which a line has existed. This requires a range of revision like
START..END where the path to blame exists in START. git blame --reverse
START is taken as git blame --reverse START..HEAD for
convenience.
--first-parent
Follow only the first parent commit upon
seeing a merge commit. This option can be used to determine when a line was
introduced to a particular integration branch, rather than when it was
introduced to the history overall.
-p, --porcelain
Show in a format designed for machine
consumption.
--line-porcelain
Show the porcelain format, but output commit
information for each line, not just the first time a commit is referenced.
Implies --porcelain.
--incremental
Show the result incrementally in a format
designed for machine consumption.
--encoding=<encoding>
Specifies the encoding used to output author
names and commit summaries. Setting it to none makes blame output
unconverted data. For more information see the discussion about encoding in
the git-log(1) manual page.
--contents <file>
When <rev> 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 the
named file (specify - to make the command read from the standard
input).
--date <format>
Specifies the format used to output dates. If
--date is not provided, the value of the blame.date config variable is used.
If the blame.date config variable is also not set, the iso format is used. For
supported values, see the discussion of the --date option at
git-log(1).
--[no-]progress
Progress status is reported on the standard
error stream by default when it is attached to a terminal. This flag enables
progress reporting even if not attached to a terminal. Can’t use
--progress together with --porcelain or
--incremental.
-M[<num>]
Detect moved or copied lines within a file.
When a commit moves or copies a block of lines (e.g. the original file has A
and then B, and the commit changes it to B and then A), the traditional
blame algorithm notices only half of the movement and 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 by running extra passes of
inspection.
<num> is optional but it is the lower bound on the number of alphanumeric
characters that Git must detect as moving/copying within a file for it to
associate those lines with the parent commit. The default value is 20.
-C[<num>]
In addition to -M, detect lines moved
or 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 additionally looks for copies
from other files in the commit that creates the file. When this option is
given three times, the command additionally looks for copies from other files
in any commit.
<num> is optional but it is the lower bound on the number of alphanumeric
characters that Git must detect as moving/copying between files for it to
associate those lines with the parent commit. And the default value is 40. If
there are more than one -C options given, the <num> argument of
the last -C will take effect.
--ignore-rev <rev>
Ignore changes made by the revision when
assigning blame, as if the change never happened. Lines that were changed or
added by an ignored commit will be blamed on the previous commit that changed
that line or nearby lines. This option may be specified multiple times to
ignore more than one revision. If the blame.markIgnoredLines config
option is set, then lines that were changed by an ignored commit and
attributed to another commit will be marked with a ? in the blame
output. If the blame.markUnblamableLines config option is set, then
those lines touched by an ignored commit that we could not attribute to
another revision are marked with a *.
--ignore-revs-file <file>
Ignore revisions listed in file, which
must be in the same format as an fsck.skipList. This option may be
repeated, and these files will be processed after any files specified with the
blame.ignoreRevsFile config option. An empty file name,
"", will clear the list of revs from previously processed
files.
--color-lines
Color line annotations in the default format
differently if they come from the same commit as the preceding line. This
makes it easier to distinguish code blocks introduced by different commits.
The color defaults to cyan and can be adjusted using the
color.blame.repeatedLines config option.
--color-by-age
Color line annotations depending on the age of
the line in the default format. The color.blame.highlightRecent config
option controls what color is used for each range of age.
-h
Show help message.
-c
Use the same output mode as
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 as having been 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 the filename in the original commit. By
default the filename is shown if there is any line that came from a file with
a different name, due to rename detection.
-n, --show-number
Show the line number in the original commit
(Default: off).
-s
Suppress the author name and timestamp from
the output.
-e, --show-email
Show the author email instead of author name
(Default: off). This can also be controlled via the blame.showEmail
config option.
-w
Ignore whitespace when comparing the
parent’s version and the child’s to find where the lines came
from.
--abbrev=<n>
Instead of using the default 7+1 hexadecimal
digits as the abbreviated object name, use <m>+1 digits, where <m>
is at least <n> but ensures the commit object names are unique. Note
that 1 column is used for a caret to mark the boundary commit.
THE DEFAULT FORMAT
When neither --porcelain nor --incremental option is specified, git blame will output annotation for each line with:•abbreviated object name for the commit
the line came from;
•author ident (by default author name
and date, unless -s or -e is specified); and
•line number
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 lines
from a different commit than the previous one, the number of lines in this
group. On subsequent lines this field is absent.
•the author name ("author"),
email ("author-mail"), time ("author-time"), and time zone
("author-tz"); similarly for committer.
•the filename in the commit that the
line is attributed to.
•the first line of the commit log
message ("summary").
# count the number of lines attributed to each author git blame --line-porcelain file | sed -n 's/^author //p' | sort | uniq -c | sort -rn
SPECIFYING RANGES
Unlike git blame and git annotate in older versions of git, the extent of the annotation can be limited to both line ranges and revision ranges. The -L option, which limits annotation to a range of lines, may be specified multiple times.git blame -L 40,60 foo git blame -L 40,+21 foo
git blame -L '/^sub hello {/,/^}$/' foo
git blame v2.6.18.. -- foo git blame --since=3.weeks -- foo
git log --diff-filter=A --pretty=short -- foo
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. 1.Each blame entry always starts with a line
of:
Line numbers count from 1.
<40-byte hex sha1> <sourceline> <resultline> <num_lines>
2.The first time that a 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 describing the extra commit
information (author, email, committer, dates, summary, etc.).
3.Unlike the Porcelain format, the filename
information is always given and terminates the entry:
and thus it is 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 between
the first and last one ("<sha1>" and "filename"
lines) where you do not 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 will not care.
"filename" <whitespace-quoted-filename-goes-here>
MAPPING AUTHORS
See gitmailmap(5).CONFIGURATION
Everything below this line in this section is selectively included from the git-config(1) documentation. The content is the same as what’s found there: blame.blankBoundaryShow blank commit object name for boundary
commits in . This option defaults to false.
blame.coloring
This determines the coloring scheme to be
applied to blame output. It can be repeatedLines,
highlightRecent, or none which is the default.
blame.date
Specifies the format used to output dates in
. If unset the iso format is used. For supported values,
see the discussion of the --date option at git-log(1).
blame.showEmail
Show the author email instead of author name
in . This option defaults to false.
blame.showRoot
Do not treat root commits as boundaries in
. This option defaults to false.
blame.ignoreRevsFile
Ignore revisions listed in the file, one
unabbreviated object name per line, in . Whitespace and
comments beginning with # are ignored. This option may be repeated
multiple times. Empty file names will reset the list of ignored revisions.
This option will be handled before the command line option
--ignore-revs-file.
blame.markUnblamableLines
Mark lines that were changed by an ignored
revision that we could not attribute to another commit with a * in the
output of .
blame.markIgnoredLines
Mark lines that were changed by an ignored
revision that we attributed to another commit with a ? in the output of
.
SEE ALSO
git-annotate(1)GIT
Part of the git(1) suite02/28/2023 | Git 2.39.2 |