#!/bin/sh
# Check for "DELME" in commit messages of about-to-be-pushed commits
####################################################################
# This hook script is triggered by `git push` right after a connection to the remote
# was established and its initial response was received, and right before generating
# and pushing a pack-file.
# The operation will be aborted when exiting with a non-zero status.
#
# The following arguments are provided:
#
# $1 - The symbolic name of the remote to push to, like "origin" or the URL like "https://github.com/Byron/gitoxide" if there is no such name.
# $2 - The URL of the remote to push to, like "https://github.com/Byron/gitoxide".
#
# The hook should then read from standard input in a line-by-line fashion and split the following space-separated fields:
#
# * local ref - the left side of a ref-spec, i.e. "local" of the "local:refs/heads/remote" ref-spec
# * local hash - the hash of the commit pointed to by `local ref`
# * remote ref - the right side of a ref-spec, i.e. "refs/heads/remote" of the "local:refs/heads/remote" ref-spec
# * remote hash - the hash of the commit pointed to by `remote ref`
#
# In this example, we abort the push if any of the about-to-be-pushed commits have "DELME" in their commit message.
#
# To enable this hook remove the `.sample` suffix from this file entirely.

remote="$1"
url="$2"

# Check each commit being pushed
while read _local_ref local_hash _remote_ref _remote_hash; do
  # Skip if the local hash is all zeroes (deletion)
  zero_sha=$(printf "%0${#local_hash}d" 0)
  if [ "$local_hash" = "$zero_sha" ]; then
    continue
  fi
  # Get the commit message
  commit_msg=$(git log --format=%s -n 1 "$local_hash")

  # Check if the commit message contains "DELME"
  if echo "$commit_msg" | grep -iq "DELME"; then
    echo "Error: Found commit with 'DELME' in message. Push aborted to $remote ($url) aborted." 1>&2
    exit 1
  fi
done

# If no commit with "DELME" found, allow the push
exit 0