Reset branch

reset.sh

#!/bin/bash

# Resets the `staging` branch to the contents of the `production` branch,
# all while maintaining history of both trees, harshly.

PRODUCTION="${1}"
STAGING="${2}"

if [ -z "${PRODUCTION}" -o -z "${STAGING}" ]; then
    echo "Usage: reset.sh <production> <staging>"
    exit 1
fi

if git diff --exit-code "${PRODUCTION}"..."${STAGING}" > /dev/null; then
    echo "No diff between branches"
    exit 0
fi

# Create a new lineage, from the tree that we want to keep
git switch -c "new-${STAGING}" "${PRODUCTION}"

# Merge, keeping history of both branches, but discarding any diffs in STAGING
git merge -s ours "${STAGING}" -m "Resetting ${STAGING} to ${PRODUCTION}"

# STAGING is obsolete, can be easily removed
git branch -d "${STAGING}"
# so that "new-STAGING" becomes "STAGING"
git branch -m "${STAGING}"