From e21a04ca573b574108f3a7ef0419bfc72ba26d4d Mon Sep 17 00:00:00 2001
From: Kevin Davis <karzak@users.noreply.github.com>
Date: Wed, 10 Mar 2021 10:56:23 -0700
Subject: [PATCH] fix: set previous block time correctly on block one (#868)

* fix: set previous block time correctly on block one

* fix failing tests
---
 x/validator-vesting/abci.go               | 10 ++++------
 x/validator-vesting/abci_test.go          |  3 ++-
 x/validator-vesting/genesis.go            |  5 ++++-
 x/validator-vesting/keeper/keeper.go      |  6 +++---
 x/validator-vesting/keeper/keeper_test.go |  9 ++++++---
 5 files changed, 19 insertions(+), 14 deletions(-)

diff --git a/x/validator-vesting/abci.go b/x/validator-vesting/abci.go
index ac714946..1bebce04 100644
--- a/x/validator-vesting/abci.go
+++ b/x/validator-vesting/abci.go
@@ -2,9 +2,6 @@ package validatorvesting
 
 import (
 	"bytes"
-	"time"
-
-	tmtime "github.com/tendermint/tendermint/types/time"
 
 	sdk "github.com/cosmos/cosmos-sdk/types"
 
@@ -15,9 +12,10 @@ import (
 
 // BeginBlocker updates the vote signing information for each validator vesting account, updates account when period changes, and updates the previousBlockTime value in the store.
 func BeginBlocker(ctx sdk.Context, req abci.RequestBeginBlock, k keeper.Keeper) {
-	previousBlockTime := tmtime.Canonical(time.Unix(0, 0))
-	if ctx.BlockHeight() > 1 {
-		previousBlockTime = k.GetPreviousBlockTime(ctx)
+	previousBlockTime, found := k.GetPreviousBlockTime(ctx)
+	if !found {
+		k.SetPreviousBlockTime(ctx, ctx.BlockTime())
+		return
 	}
 
 	currentBlockTime := ctx.BlockTime()
diff --git a/x/validator-vesting/abci_test.go b/x/validator-vesting/abci_test.go
index 60d3a050..6c97ae78 100644
--- a/x/validator-vesting/abci_test.go
+++ b/x/validator-vesting/abci_test.go
@@ -69,7 +69,7 @@ func TestBeginBlockerZeroHeight(t *testing.T) {
 			}},
 		},
 	}
-
+	vvk.SetPreviousBlockTime(ctx, now)
 	BeginBlocker(ctx, req, vvk)
 
 	vva = vvk.GetAccountFromAuthKeeper(ctx, vva.Address)
@@ -147,6 +147,7 @@ func TestBeginBlockerSignedBlock(t *testing.T) {
 		},
 	}
 
+	vvk.SetPreviousBlockTime(ctx, now)
 	BeginBlocker(ctx, req, vvk)
 	height++
 	blockTime = addHour(blockTime)
diff --git a/x/validator-vesting/genesis.go b/x/validator-vesting/genesis.go
index 00b6fd5f..fb083f44 100644
--- a/x/validator-vesting/genesis.go
+++ b/x/validator-vesting/genesis.go
@@ -22,6 +22,9 @@ func InitGenesis(ctx sdk.Context, keeper Keeper, accountKeeper types.AccountKeep
 
 // ExportGenesis returns empty genesis state because auth exports all the genesis state we need.
 func ExportGenesis(ctx sdk.Context, keeper Keeper) types.GenesisState {
-	prevBlockTime := keeper.GetPreviousBlockTime(ctx)
+	prevBlockTime, found := keeper.GetPreviousBlockTime(ctx)
+	if !found {
+		prevBlockTime = ctx.BlockTime()
+	}
 	return NewGenesisState(prevBlockTime)
 }
diff --git a/x/validator-vesting/keeper/keeper.go b/x/validator-vesting/keeper/keeper.go
index 5469578a..3357eb7c 100644
--- a/x/validator-vesting/keeper/keeper.go
+++ b/x/validator-vesting/keeper/keeper.go
@@ -43,14 +43,14 @@ func (k Keeper) Logger(ctx sdk.Context) log.Logger {
 }
 
 // GetPreviousBlockTime get the blocktime for the previous block
-func (k Keeper) GetPreviousBlockTime(ctx sdk.Context) (blockTime time.Time) {
+func (k Keeper) GetPreviousBlockTime(ctx sdk.Context) (blockTime time.Time, found bool) {
 	store := ctx.KVStore(k.storeKey)
 	b := store.Get(types.BlocktimeKey)
 	if b == nil {
-		panic("Previous block time not set")
+		return time.Time{}, false
 	}
 	k.cdc.MustUnmarshalBinaryLengthPrefixed(b, &blockTime)
-	return blockTime
+	return blockTime, true
 }
 
 // SetPreviousBlockTime set the time of the previous block
diff --git a/x/validator-vesting/keeper/keeper_test.go b/x/validator-vesting/keeper/keeper_test.go
index 4f15b003..736c5864 100644
--- a/x/validator-vesting/keeper/keeper_test.go
+++ b/x/validator-vesting/keeper/keeper_test.go
@@ -67,19 +67,22 @@ func TestGetSetPreviousBlock(t *testing.T) {
 	now := tmtime.Now()
 
 	// require panic if the previous blocktime was never set
-	require.Panics(t, func() { keeper.GetPreviousBlockTime(ctx) })
+	_, found := keeper.GetPreviousBlockTime(ctx)
+	require.False(t, found)
 
 	// require that passing a valid time to SetPreviousBlockTime does not panic
 	require.NotPanics(t, func() { keeper.SetPreviousBlockTime(ctx, now) })
 
 	// require that the value from GetPreviousBlockTime equals what was set
-	bpt := keeper.GetPreviousBlockTime(ctx)
+	bpt, found := keeper.GetPreviousBlockTime(ctx)
+	require.True(t, found)
 	require.Equal(t, now, bpt)
 
 	// require that the zero value is safe
 	require.NotPanics(t, func() { keeper.SetPreviousBlockTime(ctx, tmtime.Canonical(time.Unix(0, 0))) })
 
-	bpt = keeper.GetPreviousBlockTime(ctx)
+	bpt, found = keeper.GetPreviousBlockTime(ctx)
+	require.True(t, found)
 	require.Equal(t, tmtime.Canonical(time.Unix(0, 0)), bpt)
 
 }