R4R: Distr-PR-2 Truncate Decimal Functionality

PENDING.md

@@ -51,6 +51,7 @@ BREAKING CHANGES
     * [codec] \#2324 All referrences to wire have been renamed to codec. Additionally, wire.NewCodec is now codec.New().
     * [types] \#2343 Make sdk.Msg have a names field, to facilitate automatic tagging.
     * [baseapp] \#2366 Automatically add action tags to all messages
+    * [x/staking] \#2244 staking now holds a consensus-address-index instead of a consensus-pubkey-index
 
 * Tendermint
 

docs/spec/staking/state.md

@@ -43,12 +43,13 @@ type Params struct {
 Validators are identified according to the `OperatorAddr`, an SDK validator
 address for the operator of the validator.
 
-Validators also have a `ConsPubKey`, the public key of the validator.
-
-Validators are indexed in the store using the following maps:
+Validators also have a `ConsPubKey`, the public key of the validator used in
+Tendermint consensus. The validator can be retrieved from it's `ConsPubKey`
+once it can be converted into the corresponding `ConsAddr`. Validators are
+indexed in the store using the following maps:
 
 - Validators: `0x02 | OperatorAddr -> amino(validator)`
-- ValidatorsByPubKey: `0x03 | ConsPubKey -> OperatorAddr`
+- ValidatorsByConsAddr: `0x03 | ConsAddr -> OperatorAddr`
 - ValidatorsByPower: `0x05 | power | blockHeight | blockTx  -> OperatorAddr`
 
 `Validators` is the primary index - it ensures that each operator can have only one
@@ -69,7 +70,7 @@ validator.
 
 ```golang
 type Validator struct {
-    ConsensusPubKey crypto.PubKey  // Tendermint consensus pubkey of validator
+    ConsPubKey      crypto.PubKey  // Tendermint consensus pubkey of validator
     Jailed          bool           // has the validator been jailed?
 
     Status          sdk.BondStatus // validator status (bonded/unbonding/unbonded)

examples/democoin/mock/validator.go

@@ -24,7 +24,12 @@ func (v Validator) GetOperator() sdk.ValAddress {
 }
 
 // Implements sdk.Validator
-func (v Validator) GetPubKey() crypto.PubKey {
+func (v Validator) GetConsPubKey() crypto.PubKey {
+	return nil
+}
+
+// Implements sdk.Validator
+func (v Validator) GetConsAddr() sdk.ConsAddress {
 	return nil
 }
 
@@ -88,7 +93,12 @@ func (vs *ValidatorSet) Validator(ctx sdk.Context, addr sdk.ValAddress) sdk.Vali
 }
 
 // ValidatorByPubKey implements sdk.ValidatorSet
-func (vs *ValidatorSet) ValidatorByPubKey(ctx sdk.Context, pubkey crypto.PubKey) sdk.Validator {
+func (vs *ValidatorSet) ValidatorByConsPubKey(_ sdk.Context, _ crypto.PubKey) sdk.Validator {
+	panic("not implemented")
+}
+
+// ValidatorByPubKey implements sdk.ValidatorSet
+func (vs *ValidatorSet) ValidatorByConsAddr(_ sdk.Context, _ sdk.ConsAddress) sdk.Validator {
 	panic("not implemented")
 }
 
@@ -122,21 +132,21 @@ func (vs *ValidatorSet) RemoveValidator(addr sdk.AccAddress) {
 }
 
 // Implements sdk.ValidatorSet
-func (vs *ValidatorSet) Slash(ctx sdk.Context, pubkey crypto.PubKey, height int64, power int64, amt sdk.Dec) {
+func (vs *ValidatorSet) Slash(_ sdk.Context, _ sdk.ConsAddress, _ int64, _ int64, _ sdk.Dec) {
 	panic("not implemented")
 }
 
 // Implements sdk.ValidatorSet
-func (vs *ValidatorSet) Jail(ctx sdk.Context, pubkey crypto.PubKey) {
+func (vs *ValidatorSet) Jail(_ sdk.Context, _ sdk.ConsAddress) {
 	panic("not implemented")
 }
 
 // Implements sdk.ValidatorSet
-func (vs *ValidatorSet) Unjail(ctx sdk.Context, pubkey crypto.PubKey) {
+func (vs *ValidatorSet) Unjail(_ sdk.Context, _ sdk.ConsAddress) {
 	panic("not implemented")
 }
 
 // Implements sdk.ValidatorSet
-func (vs *ValidatorSet) Delegation(ctx sdk.Context, addrDel sdk.AccAddress, addrVal sdk.ValAddress) sdk.Delegation {
+func (vs *ValidatorSet) Delegation(_ sdk.Context, _ sdk.AccAddress, _ sdk.ValAddress) sdk.Delegation {
 	panic("not implemented")
 }

types/decimal.go

@@ -323,6 +323,32 @@ func (d Dec) RoundInt() Int {
 
 //___________________________________________________________________________________
 
+// similar to chopPrecisionAndRound, but always rounds down
+func chopPrecisionAndTruncate(d *big.Int) *big.Int {
+	return d.Quo(d, precisionReuse)
+}
+
+func chopPrecisionAndTruncateNonMutative(d *big.Int) *big.Int {
+	tmp := new(big.Int).Set(d)
+	return chopPrecisionAndTruncate(tmp)
+}
+
+// RoundInt64 rounds the decimal using bankers rounding
+func (d Dec) TruncateInt64() int64 {
+	chopped := chopPrecisionAndTruncateNonMutative(d.Int)
+	if !chopped.IsInt64() {
+		panic("Int64() out of bound")
+	}
+	return chopped.Int64()
+}
+
+// RoundInt round the decimal using bankers rounding
+func (d Dec) TruncateInt() Int {
+	return NewIntFromBigInt(chopPrecisionAndTruncateNonMutative(d.Int))
+}
+
+//___________________________________________________________________________________
+
 // reuse nil values
 var (
 	nilAmino string

types/decimal_test.go

@@ -202,6 +202,32 @@ func TestBankerRoundChop(t *testing.T) {
 	}
 }
 
+func TestTruncate(t *testing.T) {
+	tests := []struct {
+		d1  Dec
+		exp int64
+	}{
+		{mustNewDecFromStr(t, "0"), 0},
+		{mustNewDecFromStr(t, "0.25"), 0},
+		{mustNewDecFromStr(t, "0.75"), 0},
+		{mustNewDecFromStr(t, "1"), 1},
+		{mustNewDecFromStr(t, "1.5"), 1},
+		{mustNewDecFromStr(t, "7.5"), 7},
+		{mustNewDecFromStr(t, "7.6"), 7},
+		{mustNewDecFromStr(t, "7.4"), 7},
+		{mustNewDecFromStr(t, "100.1"), 100},
+		{mustNewDecFromStr(t, "1000.1"), 1000},
+	}
+
+	for tcIndex, tc := range tests {
+		resNeg := tc.d1.Neg().TruncateInt64()
+		require.Equal(t, -1*tc.exp, resNeg, "negative tc %d", tcIndex)
+
+		resPos := tc.d1.TruncateInt64()
+		require.Equal(t, tc.exp, resPos, "positive tc %d", tcIndex)
+	}
+}
+
 func TestToLeftPadded(t *testing.T) {
 	tests := []struct {
 		dec    Dec

types/stake.go

@@ -37,22 +37,23 @@ func (b BondStatus) Equal(b2 BondStatus) bool {
 
 // validator for a delegated proof of stake system
 type Validator interface {
-	GetJailed() bool          // whether the validator is jailed
-	GetMoniker() string       // moniker of the validator
-	GetStatus() BondStatus    // status of the validator
-	GetOperator() ValAddress  // operator address to receive/return validators coins
-	GetPubKey() crypto.PubKey // validation pubkey
-	GetPower() Dec            // validation power
-	GetTokens() Dec           // validation tokens
-	GetDelegatorShares() Dec  // Total out standing delegator shares
-	GetBondHeight() int64     // height in which the validator became active
+	GetJailed() bool              // whether the validator is jailed
+	GetMoniker() string           // moniker of the validator
+	GetStatus() BondStatus        // status of the validator
+	GetOperator() ValAddress      // operator address to receive/return validators coins
+	GetConsPubKey() crypto.PubKey // validation consensus pubkey
+	GetConsAddr() ConsAddress     // validation consensus address
+	GetPower() Dec                // validation power
+	GetTokens() Dec               // validation tokens
+	GetDelegatorShares() Dec      // Total out standing delegator shares
+	GetBondHeight() int64         // height in which the validator became active
 }
 
 // validator which fulfills abci validator interface for use in Tendermint
 func ABCIValidator(v Validator) abci.Validator {
 	return abci.Validator{
-		PubKey:  tmtypes.TM2PB.PubKey(v.GetPubKey()),
-		Address: v.GetPubKey().Address(),
+		PubKey:  tmtypes.TM2PB.PubKey(v.GetConsPubKey()),
+		Address: v.GetConsPubKey().Address(),
 		Power:   v.GetPower().RoundInt64(),
 	}
 }
@@ -67,14 +68,15 @@ type ValidatorSet interface {
 	IterateValidatorsBonded(Context,
 		func(index int64, validator Validator) (stop bool))
 
-	Validator(Context, ValAddress) Validator            // get a particular validator by operator
-	ValidatorByPubKey(Context, crypto.PubKey) Validator // get a particular validator by signing PubKey
-	TotalPower(Context) Dec                             // total power of the validator set
+	Validator(Context, ValAddress) Validator                // get a particular validator by operator address
+	ValidatorByConsPubKey(Context, crypto.PubKey) Validator // get a particular validator by consensus PubKey
+	ValidatorByConsAddr(Context, ConsAddress) Validator     // get a particular validator by consensus address
+	TotalPower(Context) Dec                                 // total power of the validator set
 
 	// slash the validator and delegators of the validator, specifying offence height, offence power, and slash fraction
-	Slash(Context, crypto.PubKey, int64, int64, Dec)
-	Jail(Context, crypto.PubKey)   // jail a validator
-	Unjail(Context, crypto.PubKey) // unjail a validator
+	Slash(Context, ConsAddress, int64, int64, Dec)
+	Jail(Context, ConsAddress)   // jail a validator
+	Unjail(Context, ConsAddress) // unjail a validator
 
 	// Delegation allows for getting a particular delegation for a given validator
 	// and delegator outside the scope of the staking module.
@@ -87,7 +89,7 @@ type ValidatorSet interface {
 type Delegation interface {
 	GetDelegator() AccAddress // delegator AccAddress for the bond
 	GetValidator() ValAddress // validator operator address
-	GetBondShares() Dec       // amount of validator's shares
+	GetShares() Dec           // amount of validator's shares held in this delegation
 }
 
 // properties for the set of all delegations for a particular