Git Branch Merge
Merging Branches
We have the emergency fix ready, and so let's merge the master and emergency-fix branches. First, we need to change to the master branch:
Switched to branch 'master'
Now we merge the current branch (master) with emergency-fix:
Updating 09f4acd..dfa79db
Fast-forward
index.html | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
Since the emergency-fix branch came directly from master, and no other changes had been made to master while we were working, Git sees this as a continuation of master. So it can "Fast-forward", just pointing both master and emergency-fix to the same commit.
As master and emergency-fix are essentially the same now, we can delete emergency-fix, as it is no longer needed:
Deleted branch emergency-fix (was dfa79db).
Merge Conflict
Now we can move over to hello-world-images and keep working. Add another image file (img_hello_git.jpg) and change index.html, so it shows it:
Switched to branch 'hello-world-images'
<html>
<head>
<title>Hello World!</title>
<link rel="stylesheet" href="bluestyle.css"/>
</head>
<body>
<h1>Hello world!</h1>
<div>
<img src="img_hello_world.jpg" alt="Hello World from Space" style="width: 100%; max-width: 960px"/>
</div>
<p>This is the first file in my new Git Repo.</p>
<p>A new line in our file!</p>
<div>
<img src="img_hello_git.jpg" alt="Hello Git" style="width: 100%; max-width: 640px"/>
</div>
</body>
</html>
Now, we are done with our work here and can stage and commit for this branch:
$ git commit -m "added new image"
[hello-world-images 1f1584e] added new image
2 files changed, 1 insertion(+)
create mode 100644 img_hello_git.jpg
We see that index.html has been changed in both branches. Now we are ready to merge hello-world-images into master. But what will happen to the changes we recently made in master?
$ git merge hello-world-images
Auto-merging index.html
CONFLICT (content): Merge conflict in index.html
Automatic merge failed; fix conflicts and then commit the result.
The merge failed, as there is conflict between the versions for index.html. Let us check the status:
On branch master
You have unmerged paths.
(fix conflicts and run "git commit")
(use "git merge --abort" to abort the merge)
Changes to be committed:
new file: img_hello_git.jpg
new file: img_hello_world.jpg
Unmerged paths:
(use "git add ..." to mark resolution)
both modified: index.html
<!DOCTYPE html>
<html>
<head>
<title>Hello World!</title>
<link rel="stylesheet" href="bluestyle.css"/>
</head>
<body>
<h1>Hello world!</h1>
<div><img src="img_hello_world.jpg" alt="Hello World from
Space" style="width:100%;max-width:960px"></div>
<p>This is the first file in my new Git Repo.</p>
<<<<<<< HEAD
<p>This line is here to show how merging works.</p>
=======
<p>A new line in our file!</p>
<div><img src="img_hello_git.jpg" alt="Hello Git"
style="width:100%;max-width:640px"></div>
>>>>>>> hello-world-images
</body>
</html>
We can see the differences between the versions and edit it like we want:
<!DOCTYPE html>
<html>
<head>
<title>Hello World!</title>
<link rel="stylesheet" href="bluestyle.css"/>
</head>
<body>
<h1>Hello world!</h1>
<div><img src="img_hello_world.jpg" alt="Hello World from
Space" style="width:100%;max-width:960px"></div>
<p>This is the first file in my new Git Repo.</p>
<p>This line is here to show how merging works.</p>
<div>
<img src="img_hello_git.jpg" alt="Hello Git"
style="width:100%;max-width:640px">
</div>
</body>
</html>
Now we can stage index.html and check the status:
$ git status
On branch master
All conflicts fixed but you are still merging.
(use "git commit" to conclude merge)
Changes to be committed:
new file: img_hello_git.jpg
new file: img_hello_world.jpg
modified: index.html
The conflict has been fixed, and we can use commit to conclude the merge:
[master e0b6038] merged with hello-world-images after fixing conflicts
And delete the hello-world-images branch:
Deleted branch hello-world-images (was 1f1584e).
Now you have a better understanding of how branches and merging works. Time to start working with a remote repository!