git log for a portion of a file

Question

I would like to see all the git commits that affected what are currently lines x - y in one of my files. Is there a way I can do that?

Answer 1

Now git log supports the -L option like git blame. This was added in Git v1.8.4.

 -L <start>,<end>:<file>
 -L :<regex>:<file>

 Trace the evolution of the line range given by "<start>,<end>" (or
 the funcname regex <regex>) within the <file>. You may not give any
 pathspec limiters. This is currently limited to a walk starting from a
 single revision, i.e., you may only give zero or one positive revision
 arguments. You can specify this option more than once.

(git-log documentation)

Answer 2

You can use git blame with the -L option:

-L <start>,<end> 

 Annotate only the given line range. <start> and <end> can take one of these forms: 

 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 <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>.

So it will be something like below:

git blame -L 40,60 foobar

Note that git blame shows the latest revision for each line. You can also try with the --reverse option:

--reverse

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.

http://www.kernel.org/pub/software/scm/git/docs/git-blame.html

You can probably also use

gitk foobar