[test] add resharding in testnet

Signed-off-by: Leo Chen <leo@harmony.one>

internal/configs/sharding/testnet.go

@@ -12,8 +12,17 @@ var TestnetSchedule testnetSchedule
 
 type testnetSchedule struct{}
 
+const (
+	testnetV1Epoch = 1
+	testnetV2Epoch = 2
+)
+
 func (testnetSchedule) InstanceForEpoch(epoch *big.Int) Instance {
 	switch {
+	case epoch.Cmp(big.NewInt(testnetV2Epoch)) >= 0:
+		return testnetV2
+	case epoch.Cmp(big.NewInt(testnetV1Epoch)) >= 0:
+		return testnetV1
 	default: // genesis
 		return testnetV0
 	}
@@ -24,5 +33,8 @@ func (testnetSchedule) BlocksPerEpoch() uint64 {
 	return 10800
 }
 
-var testnetReshardingEpoch = make([]*big.Int, 0)
-var testnetV0 = MustNewInstance(2, 150, 150, genesis.TNHarmonyAccounts, genesis.FoundationalNodeAccounts, testnetReshardingEpoch)
+var testnetReshardingEpoch = []*big.Int{big.NewInt(0), big.NewInt(testnetV1Epoch), big.NewInt(testnetV2Epoch)}
+
+var testnetV0 = MustNewInstance(2, 150, 150, genesis.TNHarmonyAccounts, genesis.TNFoundationalAccounts, testnetReshardingEpoch)
+var testnetV1 = MustNewInstance(2, 160, 150, genesis.TNHarmonyAccounts, genesis.TNFoundationalAccounts, testnetReshardingEpoch)
+var testnetV2 = MustNewInstance(2, 170, 150, genesis.TNHarmonyAccounts, genesis.TNFoundationalAccounts, testnetReshardingEpoch)