git
Working with Git
Git is the most popular version control system in the world. It is used to manage code, track changes, and collaborate with others. Understanding how to work with git is essential to collaborating with teams and projects around the world.
- See git for details, documentation and downloads.
- Scott Hanselman has some great explainer videos for git on his YouTube channel playlist Things they didn’t teach you at school
Git 101
I won’t try and cover it here, I’ll let Scott do the talking.
Merging Branches
- A parent branch such as master or main has been branched to develop a fix or feature
- Since the branch was made changes have been committed back onto the parent branch
- e.g. another member of the team merged changes to add a different fix or feature
- There are now changes to files on the parent branch which now block the feature branch from being successfully merged back in via a pull request
Solution
- Prior to creating a pull request changes from the parent can be merged into the feature branch as follows
git checkout <parent_branch> # could be master/main etc.
git pull # ensure that the local parent is fully up to date
git checkout <feature_branch> # switch back to working branch
git merge <parent_branch>
Auto-merging <file(s)>
CONFLICT (content): Merge conflict in <file(s)>
Automatic merge failed; fix conflicts and then commit the result. # automatic merge has failed
git mergetool # this will open the merge tool/editor configured in ~/.gitconfig
## use the editor to resolve conflicts and/or correct issues as required
## save changes and close editor
git commit # add and commit files as usual
Notes
-
Caution: when working with encrypred files such as
ansible-vaultfiles it is important to ensure that the file is decrypted before merging and then re-encrypted after the merge is complete - A good, visual, editor such as VS Code is recommended for resolving merge conflicts as it can help to identify the changes and make it easier to resolve the conflicts
Multiple Branches
Sometimes it may be necessary to work with more than one branch of a repo at the same time; for example when preparing a release branch while also working on current development features, or switching to fix a bug in one branch while continuing to work on another.
While options such as stashing and switching branches are available, it is often easier to work with multiple branches using git worktree.
Git Worktrees
git worktree allows you to checkout existing branches, or a new branch linked to the same repo
Below is an example adding a new worktree for the release/1.4.0 branch of a given repository. Notice in the prompt where when the directory is ~/Development/tooling-devops the branch shows master however when the directory is ~/Development/release-1-4 the branch shows as release/1.4.0
(~/Development/tooling-devops)
(10:35:37 on master)> git worktree add ../release-1-4 release/1.4.0
Preparing worktree (checking out 'release/1.4.0')
Updating files: 100% (696/696), done.
HEAD is now at 78cf56d Nodemonitoring Service Scaled to 5 pods
(~/Development/tooling-devops)
(10:44:47 on master)> cd ../release-1-4
(~/Development/release-1-4)
(10:45:00 on release/1.4.0)> git worktree list
/Users/grwatts/Development/toolingdevops 1ca9082 [master]
/Users/grwatts/Development/release-1-4 78cf56d [release/1.4.0]
