From a36397e21a4a95c19aafc8b9c99d4924bd538b15 Mon Sep 17 00:00:00 2001
From: Conner Fromknecht <conner@lightning.engineering>
Date: Fri, 26 Apr 2019 17:21:05 -0700
Subject: [PATCH] watchtower/wtdb/codec_test: encode/decode quick checks

---
 watchtower/wtdb/codec_test.go | 86 +++++++++++++++++++++++++++++++++++
 1 file changed, 86 insertions(+)
 create mode 100644 watchtower/wtdb/codec_test.go

diff --git a/watchtower/wtdb/codec_test.go b/watchtower/wtdb/codec_test.go
new file mode 100644
index 00000000..948ec4ee
--- /dev/null
+++ b/watchtower/wtdb/codec_test.go
@@ -0,0 +1,86 @@
+package wtdb_test
+
+import (
+	"bytes"
+	"io"
+	"reflect"
+	"testing"
+	"testing/quick"
+
+	"github.com/lightningnetwork/lnd/watchtower/wtdb"
+)
+
+// dbObject is abstract object support encoding and decoding.
+type dbObject interface {
+	Encode(io.Writer) error
+	Decode(io.Reader) error
+}
+
+// TestCodec serializes and deserializes wtdb objects in order to test that that
+// the codec understands all of the required field types. The test also asserts
+// that decoding an object into another results in an equivalent object.
+func TestCodec(t *testing.T) {
+	mainScenario := func(obj dbObject) bool {
+		// Ensure encoding the object succeeds.
+		var b bytes.Buffer
+		err := obj.Encode(&b)
+		if err != nil {
+			t.Fatalf("unable to encode: %v", err)
+			return false
+		}
+
+		var obj2 dbObject
+		switch obj.(type) {
+		case *wtdb.SessionInfo:
+			obj2 = &wtdb.SessionInfo{}
+		case *wtdb.SessionStateUpdate:
+			obj2 = &wtdb.SessionStateUpdate{}
+		default:
+			t.Fatalf("unknown type: %T", obj)
+			return false
+		}
+
+		// Ensure decoding the object succeeds.
+		err = obj2.Decode(bytes.NewReader(b.Bytes()))
+		if err != nil {
+			t.Fatalf("unable to decode: %v", err)
+			return false
+		}
+
+		// Assert the original and decoded object match.
+		if !reflect.DeepEqual(obj, obj2) {
+			t.Fatalf("encode/decode mismatch, want: %v, "+
+				"got: %v", obj, obj2)
+			return false
+		}
+
+		return true
+	}
+
+	tests := []struct {
+		name     string
+		scenario interface{}
+	}{
+		{
+			name: "SessionInfo",
+			scenario: func(obj wtdb.SessionInfo) bool {
+				return mainScenario(&obj)
+			},
+		},
+		{
+			name: "SessionStateUpdate",
+			scenario: func(obj wtdb.SessionStateUpdate) bool {
+				return mainScenario(&obj)
+			},
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			if err := quick.Check(test.scenario, nil); err != nil {
+				t.Fatalf("fuzz checks for msg=%s failed: %v",
+					test.name, err)
+			}
+		})
+	}
+}