#!/usr/bin/env bash

# Copyright 2018 The Kubernetes Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# This script checks whether mutable global feature gate is invocated correctly
# in `*_test.go` files.
# Usage: `hack/verify-test-featuregates.sh`.

set -o errexit
set -o nounset
set -o pipefail

KUBE_ROOT=$(dirname "${BASH_SOURCE[0]}")/..
source "${KUBE_ROOT}/hack/lib/init.sh"

cd "${KUBE_ROOT}"

rc=0

# find test files accessing the mutable global feature gate or interface
direct_sets=$(git grep MutableFeatureGate -- '*_test.go') || true
if [[ -n "${direct_sets}" ]]; then
  echo "Test files may not access mutable global feature gates directly:" >&2
  echo "${direct_sets}" >&2
  echo >&2
  echo "Use this invocation instead:" >&2
  echo "  defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.<FeatureName>, <value>)()" >&2
  echo >&2
  rc=1
fi

# find test files calling SetFeatureGateDuringTest and not calling the result
missing_defers=$(git grep "\\.SetFeatureGateDuringTest" -- '*_test.go' | grep -E -v "defer .*\\)\\(\\)$") || true
if [[ -n "${missing_defers}" ]]; then
  echo "Invalid invocations of featuregatetesting.SetFeatureGateDuringTest():" >&2
  echo "${missing_defers}" >&2
  echo >&2
  echo "Always make a deferred call to the returned function to ensure the feature gate is reset:" >&2
  echo "  defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.<FeatureName>, <value>)()" >&2
  echo >&2
  rc=1
fi

exit $rc
