Add kv1 -> kv3 test

ValveKeyValue/ValveKeyValue.Test/Test Data/TextKV3/array_from_kv1.kv3

@@ -0,0 +1,41 @@
+<!-- kv3 encoding:text:version{e21c7f3c-8a33-41c5-9977-a76d3a32aa0d} format:generic:version{7412167c-06e9-4698-aff2-e63eb59037e7} -->
+{
+	arrayValue = {
+		0 = "a"
+		1 = "b"
+	}
+	arrayOnSingleLine = {
+		0 = 16.7551
+		1 = 20.3763
+		2 = 19.6448
+	}
+	arrayNoSpace = {
+		0 = 1.3763
+		1 = 19.6448
+	}
+	arrayMixedTypes = {
+		0 = "a"
+		1 = "1"
+		2 = "True"
+		3 = "False"
+		4 = ""
+		5 = {
+			foo = "bar"
+		}
+		6 = {
+			0 = "1"
+			1 = "3"
+			2 = "3"
+			3 = "7"
+		}
+		7 = "11 FF"
+		8 = "hello.world"
+		9 = """
+multiline
+string
+"""
+		10 = -69.42
+	}
+	test = "success"
+	test = "success"
+}

ValveKeyValue/ValveKeyValue.Test/Test Data/TextKV3/flagged_value_from_kv1.kv3

@@ -0,0 +1,20 @@
+<!-- kv3 encoding:text:version{e21c7f3c-8a33-41c5-9977-a76d3a32aa0d} format:generic:version{7412167c-06e9-4698-aff2-e63eb59037e7} -->
+{
+	foo = "bar"
+	bar = "foo"
+	uppercase = "foo"
+	flaggedNumber = "-1234"
+	multipleFlags = "cool value"
+	soundEvent = "event sound"
+	noFlags = "5"
+	flaggedObject = {
+		1 = "test1"
+		2 = "test2"
+		3 = {
+			0 = "test3"
+		}
+		4 = "test4"
+	}
+	test = "success"
+	test = "success"
+}

ValveKeyValue/ValveKeyValue.Test/TextKV3/Kv1ToKv3TestCase.cs

@@ -0,0 +1,59 @@
+using System;
+using System.IO;
+using NUnit.Framework;
+
+namespace ValveKeyValue.Test.TextKV3
+{
+    class Kv1ToKv3TestCase
+    {
+        [Test]
+        public void SerializesBasicObjects()
+        {
+            using var stream = TestDataHelper.OpenResource("TextKV3.flagged_value_kv1.vdf");
+            var expected = TestDataHelper.ReadTextResource("TextKV3.flagged_value_from_kv1.kv3");
+
+            var kv1 = KVSerializer.Create(KVSerializationFormat.KeyValues1Text);
+            var kv3 = KVSerializer.Create(KVSerializationFormat.KeyValues3Text);
+            var data = kv1.Deserialize(stream);
+
+            data.Add(new KVObject("test", "success"));
+
+            string text;
+            using (var ms = new MemoryStream())
+            {
+                kv3.Serialize(ms, data);
+
+                ms.Seek(0, SeekOrigin.Begin);
+                using var reader = new StreamReader(ms);
+                text = reader.ReadToEnd();
+            }
+
+            Assert.That(text, Is.EqualTo(expected));
+        }
+
+        [Test]
+        public void SerializesAndKeepsLinearObjects() // TODO: Perhaps in the future KV1 arrays can use the KVArray type so it can be emitted as an array
+        {
+            using var stream = TestDataHelper.OpenResource("TextKV3.array_kv1.vdf");
+            var expected = TestDataHelper.ReadTextResource("TextKV3.array_from_kv1.kv3");
+
+            var kv1 = KVSerializer.Create(KVSerializationFormat.KeyValues1Text);
+            var kv3 = KVSerializer.Create(KVSerializationFormat.KeyValues3Text);
+            var data = kv1.Deserialize(stream);
+
+            data.Add(new KVObject("test", "success"));
+
+            string text;
+            using (var ms = new MemoryStream())
+            {
+                kv3.Serialize(ms, data);
+
+                ms.Seek(0, SeekOrigin.Begin);
+                using var reader = new StreamReader(ms);
+                text = reader.ReadToEnd();
+            }
+
+            Assert.That(text, Is.EqualTo(expected));
+        }
+    }
+}