Install git by following the instructions for your operating system here
Open a terminal and navigate to the folder you want to create the repository in.
cd <path-to-folder>
Create a folder there and enter it:
mkdir <folder-name>
cd <folder-name>
Then initialize the repository:
git init
Find the folder in the file explorer and add a README text file. When we write
git status
we can see that the file is untracked. type:
git add README.txt
to stage the file. "Write the lego instructions for it"
git status
shows us that the file is now green
git commit
This will open a text editor, and you will need to write a message to describe why you made the change and then save it. Then git will commit it and gives it a hash. "Stores all the instructions in a booklet"
TEXT EDITOR HELP. You may be in a new type of editor called vim. To write here, type
ito be start writing the message. Then hitescto exit the insert mode. type:wqto save and quit.
Type git status to see that no changes are there.
This process can be repeated a lot. People usually commit too seldom. This can be done very often. It is better with too many commits than too few, as it is easier to combine them later, rather than splitting them up.
After you have done some more changes to the source code/README file, and committed this, you can push it. Always push your work after a work session, so that other people can get hold of it.
Normally this can be done with
git push
but the first time you have to set the remote("cloud destination") of where to push to. "What cloud to upload to."
For that we need to create the project/repository in the cloud. Go to the github and create a new repository and fill in the name(refered to as <repo-name>). You can leave everything else as is.
After creating the repository, look for the url that will look like https://github.com/<your username>/<repo-name>.git and copy it(referred to as <url-to-repo>)
Go back to the termial and add the remote. Remember to paste in the url to the repository.
git remote add origin <url-to-repo>
This will add a remote that is called origin, which points to the repository to the cloud.
We then need to establish that there is a branch called master ("a shelf") where we want to place the commits("instruction books") and push to it.
git push --set-upstream origin master
When you refresh the project page, you will see that your README file is now visible.
For later pushes on the same branch, you only need to type git push
Cloning To be able to download someone elses repository, you can write
git clone https://github.com/<username>/<repo-name>.git. Then you can do the same git commands.
When implementing a new feature, you normally create a new branch so that you don't disturb anyone else and you can easily revert if something goes wrong. Type
git branch
to see the available branches and the star indicates which branch you are on.
git checkout -b <new-branch-name>
creates a new branch called <new-branch-name> and switches to it. It is the -b that signifies that you are creating a new branch. Type
git branch
to see that you have created a new branch and switched to it(by looking at the star). Type
git checkout master
to switch back to the original branch. git branch will then show you that you are on master. However we want to go to the new branch and make a change, so type
git checkout <new-branch-name>
And commit some changes(like swapping out some words) to the readme file and push it to the new branch. Again we now need to say that there is a new branch in the cloud that we want to push to. This is only done once for each new branch.
git push --set-upstream origin <new-branch-name>
Meanwhile, your partner(user2) continues on the master branch. They will do some other changes in the same location in the readme file(swapping the same words for other words). Make sure they call git branch so they know that they are doing changes to the correct branch commit and push this to master.
When both have made the changes, committed them, and pushed them, it is time to merge the two branches together.
git fetch
gets all the updates from the cloud, on other branches as well.
git branch
should show the branch created by user1. change to the branch with
git checkout <new-branch-name>
and type
git pull
to update the branch. Then switch back to the master branch by typing
git checkout master
Then we want to merge the changes into master by typing
git merge <new-branch-name>
And there will (hopefully) be a conflict. You will need to resolve this in a code editor and then stage and commit it. For more details look at these instructions from point 5 to 7.
We will have push restrictions on master branches, so that you can't push to the master branches. So to be able to merge new changes into branches by create merge requests.
Merge requests enable other users to review the code and leave comments to improve the code before merging.
Start by creating a new branch, and make some changes to it
Then push it to the cloud. Go into the repository page, and click on PUll Request in the sidebar.
Click on New Pull Request and select the source branch.
This is the branch that has the new changes.
The target branch is the branch you want to make changes to.
Click Compare branches and continue.
Write a title and description.
Here you describe why you want to change, and what areas are of special interest and request feedback for.
You can then click Submit pull request.
Now the merge request is available for others to see and comment. The other partner can try out commenting the changes. They can also add commits to the same branch and the merge request can be updated.
When all the comments are resolved, you can merge the request and the changes will appear in the target branch.
To get more familiar with branching, you can go to these sites:
https://learngitbranching.js.org/