cherry-pick.sh

#!/usr/bin/env bash

# See HACKING.md for usage
source "$(dirname "${BASH_SOURCE}")/lib/init.sh"

repo="${UPSTREAM_REPO:-k8s.io/kubernetes}"
UPSTREAM_REPO_LOCATION="${UPSTREAM_REPO_LOCATION:-../../../${repo}}"

if [[ "$#" -ne 1 ]]; then
  echo "You must supply a pull request by number or a Git range in the upstream ${repo} project" 1>&2
  exit 1
fi

pr="$1"

os::build::require_clean_tree # Origin tree must be clean

patch="${TMPDIR:-/tmp}/patch"
rm -rf "${patch}"
mkdir -p "${patch}"
patch="${patch}/cherry-pick"

if [[ ! -d "${UPSTREAM_REPO_LOCATION}" ]]; then
  echo "Expected ${UPSTREAM_REPO_LOCATION} to exist" 1>&2
  exit 1
fi

pushd "${UPSTREAM_REPO_LOCATION}" > /dev/null
os::build::require_clean_tree

remote="${UPSTREAM_REMOTE:-origin}"
downstream_remote="${DOWNSTREAM_REMOTE:-openshift}"
git fetch ${remote}
git fetch ${downstream_remote}

lastrev="${NO_REBASE-}"
if [[ -z "${NO_REBASE-}" ]]; then
  lastrev=$(python -c 'import yaml,sys; x=[i["version"] for i in yaml.safe_load(sys.stdin)["import"] if i["package"] == "'"${repo}"'"]; print(x[0] if len(x) > 0 else "")' < ${OS_ROOT}/glide.yaml)
  # resolve qualify branches from ${remote}
  if [ -z "${lastrev}" ]; then
    echo "Cannot find version of ${repo} in ${OS_ROOT}/glide.lock"
    exit 1
  fi
  if git rev-parse --verify "${downstream_remote}/${lastrev}" &>/dev/null; then
    lastrev=$(git rev-parse "${downstream_remote}/${lastrev}")
  fi
fi

if [[ "${1}" == *".."* ]]; then
  selector=$1
  pr="TODO"
elif [[ -n "${APPLY_PR_COMMITS-}" ]]; then
  selector="$(os::build::commit_range $pr ${remote}/${UPSTREAM_BRANCH:-master})"
else
  pr_commit="$(git rev-parse ${remote}/pr/$1)"
  echo "++ PR merge commit on branch ${UPSTREAM_BRANCH:-master}: ${pr_commit}"
  selector="${pr_commit}^1..${pr_commit}"
fi

if [[ -z "${NO_REBASE-}" ]]; then
  echo "++ Generating patch for ${selector} onto ${lastrev} ..." 2>&1
  if git rev-parse last_upstream_branch > /dev/null 2>&1; then
    git branch -d last_upstream_branch
  fi
  git checkout -b last_upstream_branch "${lastrev}"
  git diff -p --raw --binary "${selector}" > "${patch}"
  if ! git apply -3 "${patch}"; then
    git rerere # record pre state
    echo 2>&1
    echo "++ Merge conflicts when generating patch, please resolve conflicts and then press ENTER to continue" 1>&2
    read
  fi
  git rerere # record post state
  # stage any new files
  git add . > /dev/null
  # construct a new patch
  git diff --cached -p --raw --binary --{src,dst}-prefix=a/vendor/${repo}/ > "${patch}"
  # cleanup the current state
  git reset HEAD --hard > /dev/null
  git checkout master > /dev/null
  git branch -D last_upstream_branch > /dev/null
else
  echo "++ Generating patch for ${selector} without rebasing ..." 2>&1
  git diff -p --raw --binary --{src,dst}-prefix=a/vendor/${repo}/ "${selector}" > "${patch}"
fi

popd > /dev/null

echo "++ Applying patch ..." 2>&1
echo 2>&1
set +e
git apply --reject "${patch}"
if [[ $? -ne 0 ]]; then
  echo "++ Not all patches applied, merge *.rej into your files or rerun with REBASE=1"
  exit 1
fi

commit_message="UPSTREAM: $pr: Cherry-picked"
if [ "$repo" != "k8s.io/kubernetes" ]; then
  commit_message="UPSTREAM: $repo: $pr: Cherry-picked"
fi

set -o errexit
git add .
git commit -m "$commit_message" > /dev/null
git commit --amend
echo 2>&1
echo "++ Done" 2>&1