To use this hook:
prepare-commit-msg file at .git/hooks/prepare-commit-msg and edit as neededchmod +x .git/hooks/prepare-commit-msggit config branch.master.mergeoptions "--no-ff"NOTE: after a failed merge from a forbidden branch, the working tree will still be in a MERGING state. To discard the local working copy state, run:
git reset --merge
| #!/usr/bin/env ruby | |
| # This git hook will prevent merging specific branches into master | |
| # Put this file in your local repo, in the .git/hooks folder | |
| # and make sure it is executable. | |
| # The name of the file *must* be "prepare-commit-msg" for Git to pick it up. | |
| FORBIDDEN_BRANCHES = ["staging"] | |
| def merge? | |
| ARGV[1] == "merge" | |
| end | |
| def into_master? | |
| current_branch = `git branch | grep '*' | sed 's/* //'`.chop | |
| current_branch == "master" | |
| end | |
| def merge_msg | |
| @msg ||= `cat .git/MERGE_MSG` | |
| end | |
| def from_branch | |
| @from_branch = merge_msg.match(/Merge branch '(.*?)'/)[1] | |
| end | |
| def from_forbidden_branch? | |
| FORBIDDEN_BRANCHES.include?(from_branch) | |
| end | |
| if merge? && into_master? && from_forbidden_branch? | |
| out = `git reset --merge` | |
| puts | |
| puts " STOP THE PRESSES!" | |
| puts " You are trying to merge #{from_branch} into the *master* branch." | |
| puts " Surely you don't mean that?" | |
| puts | |
| puts " run the following command now to discard your working tree changes:" | |
| puts | |
| puts " git reset --merge" | |
| puts | |
| exit 1 | |
| end |
If you are interested, I wrote the same in Bash, as sayd.
My purpose was different: avoid merge from remote branches other than master to master, so the logic is a bit different.
https://gist.github.com/hujuice/9ff2fd4221e2135f946931dbb512bfc6#file-prepare-commit-msg
Note that I've found three types of MERGE_MSG.
What I hate and I cannot resolve is the suggestion provided by git at the end: git encourages to perform the commit.
Git says «Not committing merge; use 'git commit' to complete the merge.» as very last line. Git has the last world, grrr.
Do you have ideas about?