github.com/yinchengtsinghua/golang-Eos-dpos-Ethereum@v0.0.0-20190121132951-92cc4225ed8e/consensus/ethash/ethash_test.go

//此源码被清华学神尹成大魔王专业翻译分析并修改
//尹成QQ77025077
//尹成微信18510341407
//尹成所在QQ群721929980
//尹成邮箱 yinc13@mails.tsinghua.edu.cn
//尹成毕业于清华大学,微软区块链领域全球最有价值专家
//https://mvp.microsoft.com/zh-cn/PublicProfile/4033620
//版权所有2017 Go Ethereum作者
//此文件是Go以太坊库的一部分。
//
//Go-Ethereum库是免费软件：您可以重新分发它和/或修改
//根据GNU发布的较低通用公共许可证的条款
//自由软件基金会，或者许可证的第3版，或者
//（由您选择）任何更高版本。
//
//Go以太坊图书馆的发行目的是希望它会有用，
//但没有任何保证；甚至没有
//适销性或特定用途的适用性。见
//GNU较低的通用公共许可证，了解更多详细信息。
//
//你应该收到一份GNU较低级别的公共许可证副本
//以及Go以太坊图书馆。如果没有，请参见<http://www.gnu.org/licenses/>。

package ethash

import (
	"io/ioutil"
	"math/big"
	"math/rand"
	"os"
	"sync"
	"testing"
	"time"

	"github.com/ethereum/go-ethereum/common"
	"github.com/ethereum/go-ethereum/common/hexutil"
	"github.com/ethereum/go-ethereum/core/types"
)

//测试ethash在测试模式下是否正常工作。
func TestTestMode(t *testing.T) {
	header := &types.Header{Number: big.NewInt(1), Difficulty: big.NewInt(100)}

	ethash := NewTester(nil)
	defer ethash.Close()

	block, err := ethash.Seal(nil, types.NewBlockWithHeader(header), nil)
	if err != nil {
		t.Fatalf("failed to seal block: %v", err)
	}
	header.Nonce = types.EncodeNonce(block.Nonce())
	header.MixDigest = block.MixDigest()
	if err := ethash.VerifySeal(nil, header); err != nil {
		t.Fatalf("unexpected verification error: %v", err)
	}
}

//此测试检查高速缓存LRU逻辑在负载下是否崩溃。
//它复制了https://github.com/ethereum/go-ethereum/issues/14943
func TestCacheFileEvict(t *testing.T) {
	tmpdir, err := ioutil.TempDir("", "ethash-test")
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(tmpdir)
	e := New(Config{CachesInMem: 3, CachesOnDisk: 10, CacheDir: tmpdir, PowMode: ModeTest}, nil)
	defer e.Close()

	workers := 8
	epochs := 100
	var wg sync.WaitGroup
	wg.Add(workers)
	for i := 0; i < workers; i++ {
		go verifyTest(&wg, e, i, epochs)
	}
	wg.Wait()
}

func verifyTest(wg *sync.WaitGroup, e *Ethash, workerIndex, epochs int) {
	defer wg.Done()

	const wiggle = 4 * epochLength
	r := rand.New(rand.NewSource(int64(workerIndex)))
	for epoch := 0; epoch < epochs; epoch++ {
		block := int64(epoch)*epochLength - wiggle/2 + r.Int63n(wiggle)
		if block < 0 {
			block = 0
		}
		header := &types.Header{Number: big.NewInt(block), Difficulty: big.NewInt(100)}
		e.VerifySeal(nil, header)
	}
}

func TestRemoteSealer(t *testing.T) {
	ethash := NewTester(nil)
	defer ethash.Close()

	api := &API{ethash}
	if _, err := api.GetWork(); err != errNoMiningWork {
		t.Error("expect to return an error indicate there is no mining work")
	}
	header := &types.Header{Number: big.NewInt(1), Difficulty: big.NewInt(100)}
	block := types.NewBlockWithHeader(header)

//推动新的工作。
	ethash.Seal(nil, block, nil)

	var (
		work [3]string
		err  error
	)
	if work, err = api.GetWork(); err != nil || work[0] != block.HashNoNonce().Hex() {
		t.Error("expect to return a mining work has same hash")
	}

	if res := api.SubmitWork(types.BlockNonce{}, block.HashNoNonce(), common.Hash{}); res {
		t.Error("expect to return false when submit a fake solution")
	}
//
	header = &types.Header{Number: big.NewInt(1), Difficulty: big.NewInt(1000)}
	block = types.NewBlockWithHeader(header)
	ethash.Seal(nil, block, nil)

	if work, err = api.GetWork(); err != nil || work[0] != block.HashNoNonce().Hex() {
		t.Error("expect to return the latest pushed work")
	}
//推压块具有更高的块编号。
	newHead := &types.Header{Number: big.NewInt(2), Difficulty: big.NewInt(100)}
	newBlock := types.NewBlockWithHeader(newHead)
	ethash.Seal(nil, newBlock, nil)

	if res := api.SubmitWork(types.BlockNonce{}, block.HashNoNonce(), common.Hash{}); res {
		t.Error("expect to return false when submit a stale solution")
	}
}

func TestHashRate(t *testing.T) {
	var (
		hashrate = []hexutil.Uint64{100, 200, 300}
		expect   uint64
		ids      = []common.Hash{common.HexToHash("a"), common.HexToHash("b"), common.HexToHash("c")}
	)
	ethash := NewTester(nil)
	defer ethash.Close()

	if tot := ethash.Hashrate(); tot != 0 {
		t.Error("expect the result should be zero")
	}

	api := &API{ethash}
	for i := 0; i < len(hashrate); i += 1 {
		if res := api.SubmitHashRate(hashrate[i], ids[i]); !res {
			t.Error("remote miner submit hashrate failed")
		}
		expect += uint64(hashrate[i])
	}
	if tot := ethash.Hashrate(); tot != float64(expect) {
		t.Error("expect total hashrate should be same")
	}
}

func TestClosedRemoteSealer(t *testing.T) {
	ethash := NewTester(nil)
time.Sleep(1 * time.Second) //确保出口频道正在收听
	ethash.Close()

	api := &API{ethash}
	if _, err := api.GetWork(); err != errEthashStopped {
		t.Error("expect to return an error to indicate ethash is stopped")
	}

	if res := api.SubmitHashRate(hexutil.Uint64(100), common.HexToHash("a")); res {
		t.Error("expect to return false when submit hashrate to a stopped ethash")
	}
}