Version Control with Git

Working with Merge Conflicts

As demonstrated by the previous example, there are instances when conflicting changes can’t be merged automatically.

Let’s create another scenario with a merge conflict to explore the tools Git provides to help resolve disparities. Starting with a common hello with just the contents “hello,” let’s create two different branches with two different variants of the file:

$ git init
Initialized empty Git repository in /tmp/conflict/.git/

$ echo hello > hello
$ git add hello
$ git commit -m"Initial hello file"
Created initial commit b8725ac: Initial hello file
 1 files changed, 1 insertions(+), 0 deletions(-)
 create mode 100644 hello

$ git checkout -b alt
Switched to a new branch "alt"
$ echo world >> hello
$ echo 'Yay!' >> hello
$ git commit -a -m"One world"
Created commit d03e77f: One world
 1 files changed, 2 insertions(+), 0 deletions(-)

$ git checkout master
$ echo worlds >> hello
$ echo 'Yay!' >> hello
$ git commit -a -m"All worlds"
Created commit eddcb7d: All worlds
 1 files changed, 2 insertions(+), 0 deletions(-)

One branch says world, while the other says worlds—a deliberate difference.

As in the earlier example, if you check out master and try to merge the alt branch into it, a conflict arises:

$ git merge alt
Auto-merged hello
CONFLICT (content): Merge conflict in hello
Automatic merge failed; fix conflicts and then commit the result.

As expected, Git warns you about the conflict found in the hello file.

Locating Conflicted Files

But what if Git’s helpful ...