Git Worktree — Concurrent Development

Sometimes you have to sit on two chairs at the same time. No, I don’t mean to give you east-European political advice. I mean developing things in two concurrent branches can be a pain with the constant switching.

In my case I need to develop a stylesheet for both gtk3 and gtk4 at the same time, usually having to compare the two running concurrently. Matthias recently introduced me to the secret cabal of people knowing about git worktree. Thanks to it you can have two branches of the same project checked out at the same time, not only saving you the (cheap) drive space, but keeping a single history so cherry picking and diffing between the two doesn’t need to involve refreshing remotes or jumping through other hoops.

So let’s take a look at my scenario. I have gtk checked out in Builder, by default going to ~/Projects/gtk. The master branch equates to the new goodness of gtk4. Pushing the run button will build me gtk4-widget-factory ready to test the stylesheet. But to have the gtk3 equivalent run side by side, I don’t use a duplicate of the repo, but instead created a worktree copy:

cd ~/Projects/gtk
git checkout -tb gtk-3-24 origin/gtk-3-24 
git checkout master 
git worktree add ../gtk3 gtk-3-24

At this point you can open the gtk3 project in Builder and works as if those were not closely interconnected. But every commit is ‘visible’ in the other project.