core: Leader Selector. (#80)

1 files changed, 123 insertions, 0 deletions

diff --git a/core/leader-selector_test.go b/core/leader-selector_test.go
new file mode 100644
index 0000000..f6028c0
--- /dev/null
+++ b/core/leader-selector_test.go
@@ -0,0 +1,123 @@
+// Copyright 2018 The dexon-consensus-core Authors
+// This file is part of the dexon-consensus-core library.
+//
+// The dexon-consensus-core library is free software: you can redistribute it
+// and/or modify it under the terms of the GNU Lesser General Public License as
+// published by the Free Software Foundation, either version 3 of the License,
+// or (at your option) any later version.
+//
+// The dexon-consensus-core library is distributed in the hope that it will be
+// useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
+// General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the dexon-consensus-core library. If not, see
+// <http://www.gnu.org/licenses/>.
+
+package core
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/suite"
+
+	"github.com/dexon-foundation/dexon-consensus-core/common"
+	"github.com/dexon-foundation/dexon-consensus-core/core/types"
+	"github.com/dexon-foundation/dexon-consensus-core/crypto/eth"
+)
+
+type LeaderSelectorTestSuite struct {
+	suite.Suite
+}
+
+func (s *LeaderSelectorTestSuite) newLeader() *leaderSelector {
+	return newGenesisLeaderSelector("DEXON 🚀", eth.SigToPub)
+}
+
+func (s *LeaderSelectorTestSuite) TestDistance() {
+	leader := s.newLeader()
+	hash := common.NewRandomHash()
+	prv, err := eth.NewPrivateKey()
+	s.Require().Nil(err)
+	sig, err := prv.Sign(hash)
+	s.Require().Nil(err)
+	dis := leader.distance(sig)
+	s.True(dis.Cmp(maxHash) == -1)
+}
+
+func (s *LeaderSelectorTestSuite) TestProbability() {
+	leader := s.newLeader()
+	prv1, err := eth.NewPrivateKey()
+	s.Require().Nil(err)
+	prv2, err := eth.NewPrivateKey()
+	s.Require().Nil(err)
+	for {
+		hash := common.NewRandomHash()
+		sig1, err := prv1.Sign(hash)
+		s.Require().Nil(err)
+		sig2, err := prv2.Sign(hash)
+		s.Require().Nil(err)
+		dis1 := leader.distance(sig1)
+		dis2 := leader.distance(sig2)
+		prob1 := leader.probability(sig1)
+		prob2 := leader.probability(sig2)
+		s.True(prob1 <= 1 && prob1 >= 0)
+		s.True(prob2 <= 1 && prob2 >= 0)
+		cmp := dis1.Cmp(dis2)
+		if cmp == 0 {
+			s.True(dis1.Cmp(dis2) == 0)
+			continue
+		}
+		if cmp == 1 {
+			s.True(prob2 > prob1)
+		} else if cmp == -1 {
+			s.True(prob2 < prob1)
+		}
+		break
+	}
+}
+
+func (s *LeaderSelectorTestSuite) TestLeaderBlockHash() {
+	leader := s.newLeader()
+	blocks := make(map[common.Hash]*types.Block)
+	for i := 0; i < 10; i++ {
+		prv, err := eth.NewPrivateKey()
+		s.Require().Nil(err)
+		block := &types.Block{
+			ProposerID: types.NewValidatorID(prv.PublicKey()),
+			Hash:       common.NewRandomHash(),
+		}
+		s.Require().Nil(leader.prepareBlock(block, prv))
+		s.Require().Nil(leader.processBlock(block))
+		blocks[block.Hash] = block
+	}
+	blockHash := leader.leaderBlockHash()
+	leaderBlock, exist := blocks[blockHash]
+	s.Require().True(exist)
+	leaderDist := leader.distance(leaderBlock.CRSSignature)
+	for _, block := range blocks {
+		if block == leaderBlock {
+			continue
+		}
+		dist := leader.distance(block.CRSSignature)
+		s.True(leaderDist.Cmp(dist) == -1)
+	}
+}
+
+func (s *LeaderSelectorTestSuite) TestPrepareBlock() {
+	leader := s.newLeader()
+	prv, err := eth.NewPrivateKey()
+	s.Require().Nil(err)
+	block := &types.Block{
+		ProposerID: types.NewValidatorID(prv.PublicKey()),
+	}
+	s.Require().Nil(leader.prepareBlock(block, prv))
+	s.Nil(leader.processBlock(block))
+	block.Height++
+	s.Error(ErrIncorrectCRSSignature, leader.processBlock(block))
+}
+
+func TestLeaderSelector(t *testing.T) {
+	suite.Run(t, new(LeaderSelectorTestSuite))
+}