Git flow - create feature branch off another feature branch
I having been using git flow for a while now. I am curious to learn about a specific use case.
For one of my projects I have a ticket for a new website feature. This ticket depends on many sub-tasks. I would like to create a feature branch for the main ticket, and then for each sub-task create a feature branch off of the parent feature branch.
Let's assume I have a ticket PROJ-500 and I create a feature branch for it
git flow feature start PROJ-500
Then I want to integrate tickets PROJ-501 through PROJ-515 into PROJ-500 before integrating the whole thing into develop. Is there a way for me to do something like
git flow feature start PROJ-511 -b PROJ-500
Then over time these sub-tasks get completed and when their feature is finished, the branch is merged into PROJ-500.
git flow feature finish PROJ-511
The above command would merge PROJ-511 into PROJ-500
And once all sub-tasks are completed then PROJ-500 will be finished and merged into develop.
This way the new website feature is integrate into develop as a single unit rather than piecemeal.
Answer
You can create a sub-feature branch via
git flow feature start PROJ-511 feature/PROJ-500
But you cannot use the GitFlow tool to merge the branch back into the main feature branch because if you do
git flow feature finish PROJ-511
the feature will be merged into develop. Ergo sub-features are not supported, you need to do it manually.
Alternatives: The requirement is not new, though. There is an open issue as well as a fork project claiming to support finishing features into branches other than develop. I also found a pull request with an implementation of that feature. You might want to try that modification and see if you are happy with it.
Update 2019-12-13: As user Matěj Kříž just mentioned in his comment, user Tony Chemit has written an answer here a few months after mine, pointing to gitflow-avh as an alternative to the original gitflow product. It supports sub-features out of the box with the syntax shown above. Some years have passed by and nowadays the AVH edition is part of the normal installation of Git for Windows, I just verified this on my local box and tested the sub-feature option. I.e. for Windows users it just works right after Git installation.