From f94baa4d9395b7635768f5548d800132ff36958d Mon Sep 17 00:00:00 2001 From: Jacob Keller Date: Wed, 15 Feb 2017 16:22:12 -0800 Subject: reset: add an example of how to split a commit into two It is often useful to break a commit into multiple parts that are more logical separations. This can be tricky to learn how to do without the brute-force method if re-writing code or commit messages from scratch. Add a section to the git-reset documentation which shows an example process for how to use git add -p and git commit -c HEAD@{1} to interactively break a commit apart and re-use the original commit message as a starting point when making the new commit message. Signed-off-by: Jacob Keller Signed-off-by: Junio C Hamano diff --git a/Documentation/git-reset.txt b/Documentation/git-reset.txt index 25432d9..8a21198 100644 --- a/Documentation/git-reset.txt +++ b/Documentation/git-reset.txt @@ -292,6 +292,54 @@ $ git reset --keep start <3> <3> But you can use "reset --keep" to remove the unwanted commit after you switched to "branch2". +Split a commit apart into a sequence of commits:: ++ +Suppose that you have created lots of logically separate changes and commited +them together. Then, later you decide that it might be better to have each +logical chunk associated with its own commit. You can use git reset to rewind +history without changing the contents of your local files, and then successively +use `git add -p` to interactively select which hunks to include into each commit, +using `git commit -c` to pre-populate the commit message. ++ +------------ +$ git reset -N HEAD^ <1> +$ git add -p <2> +$ git diff --cached <3> +$ git commit -c HEAD@{1} <4> +... <5> +$ git add ... <6> +$ git diff --cached <7> +$ git commit ... <8> +------------ ++ +<1> First, reset the history back one commit so that we remove the original + commit, but leave the working tree with all the changes. The -N ensures + that any new files added with HEAD are still marked so that git add -p + will find them. +<2> Next, we interactively select diff hunks to add using the git add -p + facility. This will ask you about each diff hunk in sequence and you can + use simple commands such as "yes, include this", "No don't include this" + or even the very powerful "edit" facility. +<3> Once satisfied with the hunks you want to include, you should verify what + has been prepared for the first commit by using git diff --cached. This + shows all the changes that have been moved into the index and are about + to be committed. +<4> Next, commit the changes stored in the index. The -c option specifies to + pre-populate the commit message from the original message that you started + with in the first commit. This is helpful to avoid retyping it. The HEAD@{1} + is a special notation for the commit that HEAD used to be at prior to the + original reset commit (1 change ago). See linkgit:git-reflog[1] for more + details. You may also use any other valid commit reference. +<5> You can repeat steps 2-4 multiple times to break the original code into + any number of commits. +<6> Now you've split out many of the changes into their own commits, and might + no longer use the patch mode of git add, in order to select all remaining + uncommitted changes. +<7> Once again, check to verify that you've included what you want to. You may + also wish to verify that git diff doesn't show any remaining changes to be + committed later. +<8> And finally create the final commit. + DISCUSSION ---------- -- cgit v0.10.2-6-g49f6