Branch squash-merged to master, and merged back to branch

Question

My git workflow consists in feature branches squash-merged to master after they have been validated. However, I am unaware of the consequences of these squashed commits being brought back to the same branch they came from, via merge master without squash into branch.

If the merge to master weren't squashed, the merge of master back to that same branch would be trivial as many commits are the same ones.

Answer 1

This will add a new commit on your feature branch, show as be graphs:

1.master and feature branch before merge

A---B---C---D    master
     \
      E---F---G  feature

2.merge feature branch into master by squash (H is the squash commit on master):

A---B---C---D---H   master
     \
      E---F---G     feature

3.Merge master back into feature branch

 A---B---C---D---H      master
     \             \
      E---F---G-----I   feature

The new commit I is added in feature branch and the merge relationship are also create between master and feature.

If you want go back to the history structure as the second picture shows and undo the unawareness merge, you can use

git checkout feature 
git reset --hard HEAD~