How do I merge selected changes in a Git branch?

Question

I have two branches for development and deployment. I made committed some changes to the deployment branch which I wanted to merge into the development branch. Now I expected the merge command to show a conflict in such cases -

//development
$path = 'localhost';

and

//deployment
$path = 'example.com';

Instead what happens is that the deployment branch line just replaces the development branch line. I can cherry pick the commits and apply them to the development branch or make the changes manually but I thought there must be a better way to do this.

Answer 1

It will only conflict if you had of changed it in the development branch as well. So because you only changed it in Deployment its just a normal version change.

Simply don't commit that particular file in your changeset. (assuming that you made no other changes in that file)

Answer 2

Since that configuration file varies a lot, it is best to completely avoid any merge issue for this type of file.

You should versions the values of that config file in separate files:

• config_dev.values
• config_depl.values

And you would have only one versioned config.template file with placeholder for the values:

// server name for dev or deployment or other environments
$path = '@@SERVER_NAME@@'

That way, this template file doesn't change and won't be merged.
You would also version a script able to, on checkout, generate the actual config file (which wouldn't be versioned, remaining "private", ie only local to your current working directory)

If you declare that script as a content filter driver in a .gitattributes file, it will be executed automatically on git checkout, and will look for a file it recognizes as your config.template file (the script isn't pass any file name or file path, it only gets the content of each checked-out files)