You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: locking_test.go
    path of file: ./repos/cockroach/pkg/kv/kvserver/concurrency/lock
    
    the code of the file until where you have to start completion: // Copyright 2023 The Cockroach Authors.
//
// Use of this software is governed by the Business Source License
// included in the file licenses/BSL.txt.
//
// As of the Change Date specified in that file, in accordance with
// the Business Source License, use of this software will be governed
// by the Apache License, Version 2.0, included in the file
// licenses/APL.txt.

package lock_test

import (
	"context"
	"fmt"
	"testing"

	"github.com/cockroachdb/cockroach/pkg/kv/kvserver/concurrency/isolation"
	"github.com/cockroachdb/cockroach/pkg/kv/kvserver/concurrency/lock"
	"github.com/cockroachdb/cockroach/pkg/settings/cluster"
	"github.com/cockroachdb/cockroach/pkg/util/hlc"
	"github.com/cockroachdb/cockroach/pkg/util/leaktest"
	"github.com/cockroachdb/cockroach/pkg/util/log"
	"github.com/stretchr/testify/require"
)

func makeTS(nanos int64) hlc.Timestamp {
	retur
    
func TestCheckLockConflicts_NoneWithExclusive(t *testing.T) {
	defer leaktest.AfterTest(t)()
	defer log.Scope(t).Close(t)

	tsBelow := makeTS(1)
	tsLock := makeTS(2)
	tsAbove := makeTS(3)

	ctx := context.Background()
	for _, isoLock := range isolation.Levels() {
		for _, isoRead := range isolation.Levels() {
			for i, readTS := range []hlc.Timestamp{tsBelow, tsLock, tsAbove} {
				exclusiveLock := lock.MakeModeExclusive(tsLock, isoLock)
				nonLockingRead := lock.MakeModeNone(readTS, isoRead)

				expConflicts := isoLock == isolation.Serializable &&
					isoRead == isolation.Serializable && (readTS == tsLock || readTS == tsAbove)

				st := cluster.MakeTestingClusterSettings()
				// Test with the ExclusiveLocksBlockNonLockingReads cluster setting
				// enabled.
				lock.ExclusiveLocksBlockNonLockingReads.Override(ctx, &st.SV, true)
				testCheckLockConflicts(
					t,
					fmt.Sprintf("#%d non-locking read(%s) exclusive(%s)", i, isoRead, isoLock),
					nonLockingRead,
					exclusiveLock,
					st,
					expConflicts,
				)

				// Now, test with the ExclusiveLocksBlockNonLockingReads cluster setting
				// disabled, and ensure the two lock modes do not conflict.
				lock.ExclusiveLocksBlockNonLockingReads.Override(ctx, &st.SV, false)
				testCheckLockConflicts(
					t,
					fmt.Sprintf("#%d non-locking read(%s) exclusive(%s)", i, isoRead, isoLock),
					nonLockingRead,
					exclusiveLock,
					st,
					false, // should not conflict
				)
			}
		}
	}
}