Merge. One of the values of a VCS is to preserve history in detail, and merge is the only method that does that. Also, it’s easy to foul a remote branch with the other methods if someone has already pushed changes to branch 1.
Shared branches should always only move forward. Most Git-* systems support stuff like protected branches.
I personally like tidying up your own feature branch with rebasing and then merging it into main (preferably using only FF merges). However this is not scalable for some larger projects, and for example monorepos also make this hard to accomplish. In those cases the solution ends up being squash+merge.
The extra information about the squashed commits is usually persisted to these systems (GitHub PRs, GitLab MRs, etc) so you don’t really lose much, I guess. Although I do prefer keeping it all in plain git.
Merge. One of the values of a VCS is to preserve history in detail, and merge is the only method that does that. Also, it’s easy to foul a remote branch with the other methods if someone has already pushed changes to branch 1.
Shared branches should always only move forward. Most Git-* systems support stuff like protected branches.
I personally like tidying up your own feature branch with rebasing and then merging it into main (preferably using only FF merges). However this is not scalable for some larger projects, and for example monorepos also make this hard to accomplish. In those cases the solution ends up being squash+merge.
The extra information about the squashed commits is usually persisted to these systems (GitHub PRs, GitLab MRs, etc) so you don’t really lose much, I guess. Although I do prefer keeping it all in plain git.