How can I calculate the number of lines changed between two commits in git?

Question

Is there any easy way to calculate the number of lines changed between two commits in git? I know I can do a git diff, and count the lines, but this seems tedious. I'd also like to know how I can do this, including only my own commits in the linecounts.

Answer 1

git diff --stat commit1 commit2

EDIT: You have to specify the commits as well (without parameters it compares the working directory against the index). E.g.

git diff --stat HEAD^ HEAD

to compare the parent of HEAD with HEAD.

Answer 2

You want the --stat option of git diff, or if you're looking to parse this in a script, the --numstat option.

git diff --stat <commit-ish> <commit-ish>

--stat produces the human-readable output you're used to seeing after merges; --numstat produces a nice table layout that scripts can easily interpret.

I somehow missed that you were looking for doing this on multiple commits at the same time - that's a task for git log. Ron DeVera touches on this, but you can actually do a lot more than what he mentions. Since git log internally calls the diff machinery in order to print requested information, you can give it any of the diff stat options - not just --shortstat. The one single most likely answer you want is:

git log --author="Your name" --stat <commit1>..<commit2>

but you can use --numstat or --shortstat as well. git log can also select commits in a variety other ways - have a look at the documentation. You might be interested in things like --since (rather than specifying commit ranges, just select commits since last week) and --no-merges (merge commits don't actually introduce changes), as well as the pretty output options (--pretty=oneline, short, medium, full...).

Here's a one-liner to get total changes instead of per-commit changes from git log (change the commit selection options as desired - this is commits by you, from commit1 to commit2):

git log --numstat --pretty="%H" --author="Your Name" commit1..commit2 | awk 'NF==3 {plus+=$1; minus+=$2} END {printf("+%d, -%d\n", plus, minus)}'

(you have to let git log print some identifying information about the commit; I arbitrarily chose the hash, then used awk to only pick out the lines with three fields, which are the ones with the stat information)

Answer 3

Assuming that you want to compare all of your commits between abcd123 and wxyz789, inclusive:

git log abcd123^..wxyz789 --oneline --shortstat --author="Mike Surname"

This gives succinct output like:

abcd123 Made things better
 3 files changed, 14 insertions(+), 159 deletions(-)
wxyz789 Made things more betterer
 26 files changed, 53 insertions(+), 58 deletions(-)