Git hook prepare-commit-msg 以防止合并禁止的分支 - 将 Ruby 转换为 Bash

Question

I'm trying to implement a git hook to prevent users from merging our environment branches (other than main) into ticket branches. This hook is exactly what I need, except for that it's written in Ruby. I need my hook to be in bash or shell so that it's easy for all of our devs to adopt without having to modify their machines. The issue is I'm struggling with figuring out how to translate it since I'm not experienced with bash scripting for git.

Here is the script in Ruby:

#!/usr/bin/env ruby
FORBIDDEN_BRANCHES = ["uat", "support"]

def merge?
  ARGV[1] == "merge"
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? && from_forbidden_branch?
  out = `git reset --merge`
  puts
  puts " STOP THE PRESSES!"
  puts " You are trying to merge #{from_branch} into your 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

This is what I've got so far... I've figured out how to set the FORBIDDEN_BRANCHES array, and check if the current action being executed is a merge. What I'm missing is how to get the actual FROM_BRANCH (it's currently hardcoded to "support")

#!/bin/bash
FORBIDDEN_BRANCHES=("uat" "support" "develop")
FROM_BRANCH="support"
FROM_FORBIDDEN=0

for i in ${!FORBIDDEN_BRANCHES[@]}; do
  if test ${FORBIDDEN_BRANCHES[$i]} = $FROM_BRANCH
  then
    echo "Merging from $FROM_BRANCH is forbidden"
    FROM_FORBIDDEN=1
  fi
done

echo $FROM_FORBIDDEN

if test "$2" = "merge"
then
    if test $FROM_FORBIDDEN = 1
    then
        echo "STOP!"
        exit 1
    else
        echo "FROM_FORBIDDEN != 1, continuing"
    fi
else
    echo "Not merging"
fi

echo "Got to the end without errors..."

Answer 1

I didn't get an answer but I did come up with a solution of my own, if anyone else needs this hook. It could surely be better, since I'm not experienced in bash scripting but it accomplishes the goal of preventing merging from a forbidden branch into any other branch

#!/bin/bash
FORBIDDEN_BRANCHES=("uat" "support" "develop" "origin/uat" "origin/support" "origin/develop")
FROM_BRANCH="null"

MSG=`cat .git/MERGE_MSG`

[[ $MSG =~ ^'Merge branch '(.*) ]] && FROM_BRANCH=${BASH_REMATCH[1]}

if test $FROM_BRANCH != "null"
then
    FROM_BRANCH=$(echo $FROM_BRANCH | cut -f 1 -d " ")
    eval BRANCH=$FROM_BRANCH
else
    [[ $MSG =~ ^'Merge remote-tracking branch '(.*) ]] && FROM_BRANCH=${BASH_REMATCH[1]}
    FROM_BRANCH=$(echo $FROM_BRANCH | cut -f 1 -d " ")
    eval BRANCH=$FROM_BRANCH
fi

if test $FROM_BRANCH != "null"
then
    for i in ${!FORBIDDEN_BRANCHES[@]}; do
      if test ${FORBIDDEN_BRANCHES[$i]} = $BRANCH
      then
        echo "Merging from $BRANCH is forbidden"
        echo "Reset your branch using \"git reset --merge\""
        exit 1
      fi
    done
else
    "NOT COMITTING: FROM_BRANCH = $FROM_BRANCH"
fi