From 1dd874afdcb32da535ade6498b531466efd4916f Mon Sep 17 00:00:00 2001
From: Alex Peters <alpe@users.noreply.github.com>
Date: Wed, 6 Apr 2022 11:19:44 +0200
Subject: [PATCH] Add more tests for event edge cases

---
 x/wasm/keeper/events_test.go       | 16 ++++++++++
 x/wasm/keeper/gas_register_test.go | 47 ++++++++++++++++++++++++++++++
 2 files changed, 63 insertions(+)

diff --git a/x/wasm/keeper/events_test.go b/x/wasm/keeper/events_test.go
index 8c59516343..e10074a0c2 100644
--- a/x/wasm/keeper/events_test.go
+++ b/x/wasm/keeper/events_test.go
@@ -183,6 +183,13 @@ func TestNewCustomEvents(t *testing.T) {
 				sdk.NewAttribute("_contract_address", myContract.String()),
 				sdk.NewAttribute("my Key", "myVal"))},
 		},
+		"empty event elements": {
+			src:     make(wasmvmtypes.Events, 10),
+			isError: true,
+		},
+		"nil": {
+			exp: sdk.Events{},
+		},
 	}
 	for name, spec := range specs {
 		t.Run(name, func(t *testing.T) {
@@ -240,6 +247,15 @@ func TestNewWasmModuleEvent(t *testing.T) {
 				sdk.NewAttribute("_contract_address", myContract.String()),
 				sdk.NewAttribute("my-real-key", "some-val"))},
 		},
+		"empty elements": {
+			src:     make([]wasmvmtypes.EventAttribute, 10),
+			isError: true,
+		},
+		"nil": {
+			exp: sdk.Events{sdk.NewEvent("wasm",
+				sdk.NewAttribute("_contract_address", myContract.String()),
+			)},
+		},
 	}
 	for name, spec := range specs {
 		t.Run(name, func(t *testing.T) {
diff --git a/x/wasm/keeper/gas_register_test.go b/x/wasm/keeper/gas_register_test.go
index 1ecabc5fba..b3ca5b9c86 100644
--- a/x/wasm/keeper/gas_register_test.go
+++ b/x/wasm/keeper/gas_register_test.go
@@ -283,6 +283,26 @@ func TestReplyCost(t *testing.T) {
 			srcConfig: DefaultGasRegisterConfig(),
 			exp:       sdk.Gas(DefaultInstanceCost + 3*DefaultContractMessageDataCost),
 		},
+		"subcall response with empty events": {
+			src: wasmvmtypes.Reply{
+				Result: wasmvmtypes.SubcallResult{
+					Ok: &wasmvmtypes.SubcallResponse{
+						Events: make([]wasmvmtypes.Event, 10),
+					},
+				},
+			},
+			srcConfig: DefaultGasRegisterConfig(),
+			exp:       DefaultInstanceCost,
+		},
+		"subcall response with events unset": {
+			src: wasmvmtypes.Reply{
+				Result: wasmvmtypes.SubcallResult{
+					Ok: &wasmvmtypes.SubcallResponse{},
+				},
+			},
+			srcConfig: DefaultGasRegisterConfig(),
+			exp:       DefaultInstanceCost,
+		},
 	}
 	for name, spec := range specs {
 		t.Run(name, func(t *testing.T) {
@@ -298,6 +318,33 @@ func TestReplyCost(t *testing.T) {
 	}
 }
 
+func TestEventCosts(t *testing.T) {
+	// most cases are covered in TestReplyCost already. This ensures some edge cases
+	specs := map[string]struct {
+		srcAttrs  []wasmvmtypes.EventAttribute
+		srcEvents wasmvmtypes.Events
+		expGas    sdk.Gas
+	}{
+		"empty events": {
+			srcEvents: make([]wasmvmtypes.Event, 1),
+			expGas:    DefaultPerCustomEventCost,
+		},
+		"empty attributes": {
+			srcAttrs: make([]wasmvmtypes.EventAttribute, 1),
+			expGas:   DefaultPerAttributeCost,
+		},
+		"both nil": {
+			expGas: 0,
+		},
+	}
+	for name, spec := range specs {
+		t.Run(name, func(t *testing.T) {
+			gotGas := NewDefaultWasmGasRegister().EventCosts(spec.srcAttrs, spec.srcEvents)
+			assert.Equal(t, spec.expGas, gotGas)
+		})
+	}
+}
+
 func TestToWasmVMGasConversion(t *testing.T) {
 	specs := map[string]struct {
 		src       storetypes.Gas