From 8fad09a659903046bae29241bcdfbe89509b24f7 Mon Sep 17 00:00:00 2001
From: Christopher Goes <cwgoes@protonmail.ch>
Date: Mon, 2 Apr 2018 15:48:10 +0200
Subject: [PATCH] Implement InitGenesis for x/stake (closes #737)

---
 x/stake/keeper.go      | 18 +++++++++++++++---
 x/stake/test_common.go | 33 +++++++++++++++++++++++++++++++++
 x/stake/types.go       | 28 +++++-----------------------
 3 files changed, 53 insertions(+), 26 deletions(-)

diff --git a/x/stake/keeper.go b/x/stake/keeper.go
index 95eb85e76..1bd70feb7 100644
--- a/x/stake/keeper.go
+++ b/x/stake/keeper.go
@@ -2,6 +2,8 @@ package stake
 
 import (
 	"bytes"
+	"encoding/json"
+	"errors"
 
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	"github.com/cosmos/cosmos-sdk/wire"
@@ -28,6 +30,17 @@ func NewKeeper(ctx sdk.Context, cdc *wire.Codec, key sdk.StoreKey, ck bank.CoinK
 	return keeper
 }
 
+// InitGenesis - store genesis parameters
+func (k Keeper) InitGenesis(ctx sdk.Context, data json.RawMessage) error {
+	var state GenesisState
+	if err := json.Unmarshal(data, &state); err != nil {
+		return err
+	}
+	k.setPool(ctx, state.Pool)
+	k.setParams(ctx, state.Params)
+	return nil
+}
+
 //_________________________________________________________________________
 
 // get a single candidate
@@ -343,8 +356,7 @@ func (k Keeper) GetParams(ctx sdk.Context) (params Params) {
 	store := ctx.KVStore(k.storeKey)
 	b := store.Get(ParamKey)
 	if b == nil {
-		k.params = defaultParams()
-		return k.params
+		panic(errors.New("Stored params should not have been nil"))
 	}
 
 	err := k.cdc.UnmarshalBinary(b, &params)
@@ -374,7 +386,7 @@ func (k Keeper) GetPool(ctx sdk.Context) (gs Pool) {
 	store := ctx.KVStore(k.storeKey)
 	b := store.Get(PoolKey)
 	if b == nil {
-		return initialPool()
+		panic(errors.New("Stored pool should not have been nil"))
 	}
 	err := k.cdc.UnmarshalBinary(b, &gs)
 	if err != nil {
diff --git a/x/stake/test_common.go b/x/stake/test_common.go
index 03f9fe92c..c90c68b2c 100644
--- a/x/stake/test_common.go
+++ b/x/stake/test_common.go
@@ -2,6 +2,7 @@ package stake
 
 import (
 	"encoding/hex"
+	"encoding/json"
 	"testing"
 
 	"github.com/stretchr/testify/require"
@@ -52,6 +53,31 @@ var (
 	emptyPubkey crypto.PubKey
 )
 
+// default params for testing
+func defaultParams() Params {
+	return Params{
+		InflationRateChange: sdk.NewRat(13, 100),
+		InflationMax:        sdk.NewRat(20, 100),
+		InflationMin:        sdk.NewRat(7, 100),
+		GoalBonded:          sdk.NewRat(67, 100),
+		MaxValidators:       100,
+		BondDenom:           "fermion",
+	}
+}
+
+// initial pool for testing
+func initialPool() Pool {
+	return Pool{
+		TotalSupply:       0,
+		BondedShares:      sdk.ZeroRat,
+		UnbondedShares:    sdk.ZeroRat,
+		BondedPool:        0,
+		UnbondedPool:      0,
+		InflationLastTime: 0,
+		Inflation:         sdk.NewRat(7, 100),
+	}
+}
+
 // XXX reference the common declaration of this function
 func subspace(prefix []byte) (start, end []byte) {
 	end = make([]byte, len(prefix))
@@ -123,6 +149,13 @@ func createTestInput(t *testing.T, sender sdk.Address, isCheckTx bool, initCoins
 	)
 	ck := bank.NewCoinKeeper(accountMapper)
 	keeper := NewKeeper(ctx, cdc, keyStake, ck)
+	encoded, err := json.Marshal(GenesisState{initialPool(), defaultParams()})
+	if err != nil {
+		panic(err)
+	}
+	if err = keeper.InitGenesis(ctx, encoded); err != nil {
+		panic(err)
+	}
 
 	// fill all the addresses with some coins
 	for _, addr := range addrs {
diff --git a/x/stake/types.go b/x/stake/types.go
index 4ba7c59d0..9dfeeca20 100644
--- a/x/stake/types.go
+++ b/x/stake/types.go
@@ -16,19 +16,6 @@ type Params struct {
 	BondDenom     string `json:"bond_denom"`     // bondable coin denomination
 }
 
-// XXX do we want to allow for default params even or do we want to enforce that you
-// need to be explicit about defining all params in genesis?
-func defaultParams() Params {
-	return Params{
-		InflationRateChange: sdk.NewRat(13, 100),
-		InflationMax:        sdk.NewRat(20, 100),
-		InflationMin:        sdk.NewRat(7, 100),
-		GoalBonded:          sdk.NewRat(67, 100),
-		MaxValidators:       100,
-		BondDenom:           "fermion",
-	}
-}
-
 //_________________________________________________________________________
 
 // Pool - dynamic parameters of the current state
@@ -42,16 +29,11 @@ type Pool struct {
 	Inflation         sdk.Rat `json:"inflation"`           // current annual inflation rate
 }
 
-func initialPool() Pool {
-	return Pool{
-		TotalSupply:       0,
-		BondedShares:      sdk.ZeroRat,
-		UnbondedShares:    sdk.ZeroRat,
-		BondedPool:        0,
-		UnbondedPool:      0,
-		InflationLastTime: 0,
-		Inflation:         sdk.NewRat(7, 100),
-	}
+// GenesisState - all staking state that must be provided at genesis
+
+type GenesisState struct {
+	Pool   Pool   `json:"pool"`
+	Params Params `json:"params"`
 }
 
 //_______________________________________________________________________________________________________