Add unit test for negative integers.

YamlDotNet.Test/Serialization/SerializationTests.cs

@@ -1020,10 +1020,10 @@ public void SpecialFloatsAreDeserializedCorrectly()
 		[Fact]
 		public void SpecialFloatsAreSerializedCorrectly()
 		{
-			var deserializer = new Serializer();
+			var serializer = new Serializer();
 
 			var buffer = new StringWriter();
-			deserializer.Serialize(buffer, new double[]
+			serializer.Serialize(buffer, new double[]
 			{
 				double.NaN,
 				double.PositiveInfinity,
@@ -1037,6 +1037,17 @@ public void SpecialFloatsAreSerializedCorrectly()
 			Assert.Contains("- -.inf", text);
 		}
 
+		[Fact]
+		public void NegativeIntegersCanBeDeserialized()
+		{
+			var deserializer = new Deserializer();
+
+			var value = deserializer.Deserialize<int>(Yaml.ReaderForText(@"
+				'-123'
+			"));
+			Assert.Equal(-123, value);
+		}
+
 		#region Test Dictionary that implements IDictionary<,>, but not IDictionary
 		public class GenericTestDictionary<TKey, TValue> : IDictionary<TKey, TValue>
 		{