Applying Patches

First, take a look at what changes are in the patch. You can do this easily with git apply

Note that this command does not apply the patch, but only shows you the stats about what it’ll do. After peeking into the patch file with your favorite editor, you can see what the actual changes are.

Next, you’re interested in how troublesome the patch is going to be. Git allows you to test the patch before you actually apply it.

If you don’t get any errors, the patch has no conflicts. Otherwise you may see what trouble you’ll run into.

To apply a clean patch (adding the items and commit/signoff in a single step), use git am:

This preserves the original author’s commit message.

However, this can fail if the patch file does not contain the original committers email address. In this case you will need to abort the am session:

and continue on by applying a non-clean patch, as described next.

If the patch does not apply cleanly, then the original authors commit message cannot be preserved. This sequence in this case is:

Fix up any issues. The add and commit as usual

The --signoff simply adds a line to the commit message indicating you have signed off the commit.

Information adapted from this blog post and this wiki page.

If a diff file has been provided instead of a patch, then use for example the eGit’s wizards (Eclipse’s Git integration).