From a83535aef34443180c7769a3a2ed7ad04b0ef7ca Mon Sep 17 00:00:00 2001
From: Christopher Goes <cwgoes@pluranimity.org>
Date: Fri, 12 Oct 2018 21:09:23 +0200
Subject: [PATCH] Greater than to greater than or equal to

---
 docs/spec/slashing/begin-block.md |  2 +-
 x/slashing/keeper.go              |  2 +-
 x/slashing/keeper_test.go         | 85 +++++++++++++++++++++++++++++++
 3 files changed, 87 insertions(+), 2 deletions(-)

diff --git a/docs/spec/slashing/begin-block.md b/docs/spec/slashing/begin-block.md
index fb7d04e5dc..2d03fb6a7f 100644
--- a/docs/spec/slashing/begin-block.md
+++ b/docs/spec/slashing/begin-block.md
@@ -109,7 +109,7 @@ for val in block.Validators:
   // included in 50% of the recent LastCommits
   minHeight = signInfo.StartHeight + SIGNED_BLOCKS_WINDOW
   maxMissed = SIGNED_BLOCKS_WINDOW / 2
-  if height > minHeight AND signInfo.MissedBlocksCounter > maxMissed:
+  if height >= minHeight AND signInfo.MissedBlocksCounter > maxMissed:
     signInfo.JailedUntil = block.Time + DOWNTIME_UNBOND_DURATION
 
     slash & unbond the validator
diff --git a/x/slashing/keeper.go b/x/slashing/keeper.go
index 23e30fe1ec..1e0725ae8e 100644
--- a/x/slashing/keeper.go
+++ b/x/slashing/keeper.go
@@ -128,7 +128,7 @@ func (k Keeper) handleValidatorSignature(ctx sdk.Context, addr crypto.Address, p
 	}
 	minHeight := signInfo.StartHeight + k.SignedBlocksWindow(ctx)
 	maxMissed := k.SignedBlocksWindow(ctx) - k.MinSignedPerWindow(ctx)
-	if height > minHeight && signInfo.MissedBlocksCounter > maxMissed {
+	if height >= minHeight && signInfo.MissedBlocksCounter > maxMissed {
 		validator := k.validatorSet.ValidatorByConsAddr(ctx, consAddr)
 		if validator != nil && !validator.GetJailed() {
 			// Downtime confirmed: slash and jail the validator
diff --git a/x/slashing/keeper_test.go b/x/slashing/keeper_test.go
index 32469b6d30..9dcaae6e5b 100644
--- a/x/slashing/keeper_test.go
+++ b/x/slashing/keeper_test.go
@@ -364,3 +364,88 @@ func TestHandleAlreadyJailed(t *testing.T) {
 	require.Equal(t, amtInt-1, validator.GetTokens().RoundInt64())
 
 }
+
+// Test a validator dipping in and out of the validator set
+// Ensure that missed blocks are tracked correctly
+func TestValidatorDippingInAndOut(t *testing.T) {
+
+	// initial setup
+	ctx, _, sk, _, keeper := createTestInput(t)
+	params := sk.GetParams(ctx)
+	params.MaxValidators = 1
+	sk.SetParams(ctx, params)
+	amtInt := int64(100)
+	addr, val, amt := addrs[0], pks[0], sdk.NewInt(amtInt)
+	sh := stake.NewHandler(sk)
+	got := sh(ctx, newTestMsgCreateValidator(addr, val, amt))
+	require.True(t, got.IsOK())
+	validatorUpdates := stake.EndBlocker(ctx, sk)
+	keeper.AddValidators(ctx, validatorUpdates)
+
+	// 100 first blocks OK
+	height := int64(0)
+	for ; height < int64(100); height++ {
+		ctx = ctx.WithBlockHeight(height)
+		keeper.handleValidatorSignature(ctx, val.Address(), amtInt, true)
+	}
+
+	// validator kicked out of validator set
+	newAmt := int64(101)
+	got = sh(ctx, newTestMsgCreateValidator(addrs[1], pks[1], sdk.NewInt(newAmt)))
+	require.True(t, got.IsOK())
+	validatorUpdates = stake.EndBlocker(ctx, sk)
+	require.Equal(t, 2, len(validatorUpdates))
+	keeper.AddValidators(ctx, validatorUpdates)
+	validator, _ := sk.GetValidator(ctx, addr)
+	require.Equal(t, sdk.Unbonding, validator.Status)
+
+	// 600 more blocks happened
+	height = int64(700)
+	ctx = ctx.WithBlockHeight(height)
+
+	// validator added back in
+	got = sh(ctx, newTestMsgDelegate(sdk.AccAddress(addrs[2]), addrs[0], sdk.NewInt(2)))
+	require.True(t, got.IsOK())
+	validatorUpdates = stake.EndBlocker(ctx, sk)
+	require.Equal(t, 2, len(validatorUpdates))
+	validator, _ = sk.GetValidator(ctx, addr)
+	require.Equal(t, sdk.Bonded, validator.Status)
+	newAmt = int64(102)
+
+	// validator misses a block
+	keeper.handleValidatorSignature(ctx, val.Address(), newAmt, false)
+	height++
+
+	// shouldn't be jailed/kicked yet
+	validator, _ = sk.GetValidator(ctx, addr)
+	require.Equal(t, sdk.Bonded, validator.Status)
+
+	// validator misses 500 blocks
+	for ; height < int64(1202); height++ {
+		ctx = ctx.WithBlockHeight(height)
+		keeper.handleValidatorSignature(ctx, val.Address(), newAmt, false)
+	}
+
+	// should not yet be jailed & kicked
+	stake.EndBlocker(ctx, sk)
+	validator, _ = sk.GetValidator(ctx, addr)
+	require.Equal(t, sdk.Bonded, validator.Status)
+
+	// validator signs 500 blocks
+	for ; height < int64(1701); height++ {
+		ctx = ctx.WithBlockHeight(height)
+		keeper.handleValidatorSignature(ctx, val.Address(), newAmt, true)
+	}
+
+	// should have exceeded threshold
+	signingInfo, found := keeper.getValidatorSigningInfo(ctx, sdk.ConsAddress(val.Address()))
+	require.True(t, found)
+	require.Equal(t, int64(700), signingInfo.StartHeight)
+	require.Equal(t, int64(1101), signingInfo.IndexOffset)
+	require.Equal(t, int64(501), signingInfo.MissedBlocksCounter)
+
+	// should be jailed & kicked
+	stake.EndBlocker(ctx, sk)
+	validator, _ = sk.GetValidator(ctx, addr)
+	require.Equal(t, sdk.Unbonding, validator.Status)
+}