Add cached boxed boolean values to BooleanType

src/NHibernate.Test/Async/TypesTest/BooleanTypeFixture.cs

@@ -8,8 +8,10 @@
 //------------------------------------------------------------------------------
 
 
-using System;
+using System.Data.Common;
+using NHibernate.Engine;
 using NHibernate.Type;
+using NSubstitute;
 using NUnit.Framework;
 
 namespace NHibernate.Test.TypesTest
@@ -21,10 +23,7 @@ namespace NHibernate.Test.TypesTest
 	[TestFixture]
 	public class BooleanTypeFixtureAsync : TypeFixtureBase
 	{
-		protected override string TypeName
-		{
-			get { return "Boolean"; }
-		}
+		protected override string TypeName => "Boolean";
 
 		[Test]
 		public async Task ReadWriteAsync()
@@ -48,4 +47,4 @@ public async Task ReadWriteAsync()
 			s.Close();
 		}
 	}
-}
+}

src/NHibernate.Test/TypesTest/BooleanTypeFixture.cs

@@ -1,5 +1,7 @@
-using System;
+using System.Data.Common;
+using NHibernate.Engine;
 using NHibernate.Type;
+using NSubstitute;
 using NUnit.Framework;
 
 namespace NHibernate.Test.TypesTest
@@ -10,10 +12,7 @@ namespace NHibernate.Test.TypesTest
 	[TestFixture]
 	public class BooleanTypeFixture : TypeFixtureBase
 	{
-		protected override string TypeName
-		{
-			get { return "Boolean"; }
-		}
+		protected override string TypeName => "Boolean";
 
 		/// <summary>
 		/// Verify Equals will correctly determine when the property
@@ -22,7 +21,7 @@ protected override string TypeName
 		[Test]
 		public void Equals()
 		{
-			BooleanType type = (BooleanType) NHibernateUtil.Boolean;
+			BooleanType type = NHibernateUtil.Boolean;
 
 			Assert.IsTrue(type.IsEqual(true, true));
 			Assert.IsTrue(type.IsEqual(false, false));
@@ -50,5 +49,65 @@ public void ReadWrite()
 			s.Flush();
 			s.Close();
 		}
+
+		[Theory]
+		public void GetByIndex(bool expected)
+		{
+			const int index0 = 0;
+			const int index1 = 1;
+			BooleanType type = NHibernateUtil.Boolean;
+			var session = Substitute.For<ISessionImplementor>();
+			var reader = Substitute.For<DbDataReader>();
+			reader[index0].Returns(expected);
+			reader[index1].Returns(expected);
+
+			var result0 = type.Get(reader, index0, session);
+			var result1 = type.Get(reader, index1, session);
+
+			Assert.AreEqual(expected, (bool) result0);
+			Assert.AreSame(result0, result1);
+		}
+
+		[Theory]
+		public void GetByName(bool expected)
+		{
+			const string name0 = "name0";
+			const string name1 = "name1";
+			BooleanType type = NHibernateUtil.Boolean;
+			var session = Substitute.For<ISessionImplementor>();
+			var reader = Substitute.For<DbDataReader>();
+			reader[name0].Returns(expected);
+			reader[name1].Returns(expected);
+
+			var result0 = type.Get(reader, name0, session);
+			var result1 = type.Get(reader, name1, session);
+
+			Assert.AreEqual(expected, (bool) result0);
+			Assert.AreSame(result0, result1);
+		}
+
+		[Test]
+		public void DefaultValue()
+		{
+			BooleanType type = NHibernateUtil.Boolean;
+
+			var result0 = type.DefaultValue;
+			var result1 = type.DefaultValue;
+
+			Assert.IsFalse((bool) result0);
+			Assert.AreSame(result0, result1);
+		}
+
+		[Theory]
+		public void StringToObject(bool expected)
+		{
+			BooleanType type = NHibernateUtil.Boolean;
+
+			var result0 = type.StringToObject(expected.ToString());
+			var result1 = type.StringToObject(expected.ToString());
+
+			Assert.AreEqual(expected, result0);
+			Assert.AreSame(result0, result1);
+		}
 	}
-}
+}

src/NHibernate.Test/TypesTest/CharBooleanTypeFixture.cs

@@ -0,0 +1,71 @@
+using System.Data.Common;
+using NHibernate.Engine;
+using NHibernate.SqlTypes;
+using NHibernate.Type;
+using NSubstitute;
+using NUnit.Framework;
+
+namespace NHibernate.Test.TypesTest
+{
+	[TestFixture]
+	public sealed class CharBooleanTypeFixture
+	{
+		[Theory]
+		public void GetByIndex(bool expected)
+		{
+			const int index0 = 0;
+			const int index1 = 1;
+			CharBooleanType type =new CharBooleanTypeStub();
+			var session = Substitute.For<ISessionImplementor>();
+			var reader = Substitute.For<DbDataReader>();
+			reader[index0].Returns(expected.ToString());
+			reader[index1].Returns(expected.ToString());
+
+			var result0 = type.Get(reader, index0, session);
+			var result1 = type.Get(reader, index1, session);
+
+			Assert.AreEqual(expected, (bool) result0);
+			Assert.AreSame(result0, result1);
+		}
+
+		[Theory]
+		public void GetByName(bool value)
+		{
+			const string name = "0";
+			const int index = 0;
+			object expected = value;
+			CharBooleanType type = Substitute.ForPartsOf<CharBooleanTypeStub>();
+			var session = Substitute.For<ISessionImplementor>();
+			var reader = Substitute.For<DbDataReader>();
+			reader.GetOrdinal(name).Returns(index);
+			type.Get(reader, index, Arg.Any<ISessionImplementor>()).Returns(expected);
+
+			var result = type.Get(reader, name, session);
+
+			Assert.AreSame(expected, result);
+		}
+
+		[Theory]
+		public void StringToObject(bool expected)
+		{
+			CharBooleanType type = new CharBooleanTypeStub();
+
+			var result0 = type.StringToObject(expected.ToString());
+			var result1 = type.StringToObject(expected.ToString());
+
+			Assert.AreEqual(expected, result0);
+			Assert.AreSame(result0, result1);
+		}
+
+		public class CharBooleanTypeStub : CharBooleanType
+		{
+			public CharBooleanTypeStub() : base(new AnsiStringFixedLengthSqlType())
+			{
+			}
+
+			protected override string TrueString => true.ToString();
+
+			protected override string FalseString => false.ToString();
+		}
+	}
+}

src/NHibernate/Type/BooleanType.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Data;
 using System.Data.Common;
+using System.Runtime.CompilerServices;
 using NHibernate.Engine;
 using NHibernate.SqlTypes;
 
@@ -13,6 +14,9 @@ namespace NHibernate.Type
 	[Serializable]
 	public class BooleanType : PrimitiveType, IDiscriminatorType
 	{
+		protected static readonly object TrueObject = true;
+		protected static readonly object FalseObject = false;
+
 		/// <summary>
 		/// Initialize a new instance of the BooleanType
 		/// </summary>
@@ -36,38 +40,26 @@ public BooleanType(AnsiStringFixedLengthSqlType sqlType) : base(sqlType)
 
 		public override object Get(DbDataReader rs, int index, ISessionImplementor session)
 		{
-			return Convert.ToBoolean(rs[index]);
+			return GetBooleanAsObject(Convert.ToBoolean(rs[index]));
 		}
 
 		public override object Get(DbDataReader rs, string name, ISessionImplementor session)
 		{
-			return Convert.ToBoolean(rs[name]);
+			return GetBooleanAsObject(Convert.ToBoolean(rs[name]));
 		}
 
-		public override System.Type PrimitiveClass
-		{
-			get { return typeof(bool); }
-		}
+		public override System.Type PrimitiveClass => typeof(bool);
 
-		public override System.Type ReturnedClass
-		{
-			get { return typeof(bool); }
-		}
+		public override System.Type ReturnedClass => typeof(bool);
 
 		public override void Set(DbCommand cmd, object value, int index, ISessionImplementor session)
 		{
 			cmd.Parameters[index].Value = (bool) value;
 		}
 
-		public override string Name
-		{
-			get { return "Boolean"; }
-		}
+		public override string Name => "Boolean";
 
-		public override object DefaultValue
-		{
-			get { return false; }
-		}
+		public override object DefaultValue => FalseObject;
 
 		public override string ObjectToSQLString(object value, Dialect.Dialect dialect)
 		{
@@ -89,7 +81,13 @@ public virtual object StringToObject(string xml)
 		[Obsolete("This method has no more usages and will be removed in a future version.")]
 		public override object FromStringValue(string xml)
 		{
-			return bool.Parse(xml);
+			return GetBooleanAsObject(bool.Parse(xml));
+		}
+
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		internal static object GetBooleanAsObject(bool value)
+		{
+			return value ? TrueObject : FalseObject;
 		}
 	}
 }

src/NHibernate/Type/CharBooleanType.cs

@@ -3,7 +3,6 @@
 using System.Data.Common;
 using NHibernate.Engine;
 using NHibernate.SqlTypes;
-using NHibernate.Util;
 
 namespace NHibernate.Type
 {
@@ -37,7 +36,7 @@ public override object Get(DbDataReader rs, int index, ISessionImplementor sessi
 			}
 			else
 			{
-				return code.Equals(TrueString, StringComparison.InvariantCultureIgnoreCase);
+				return GetBooleanAsObject(code.Equals(TrueString, StringComparison.InvariantCultureIgnoreCase));
 			}
 		}
 
@@ -68,11 +67,11 @@ public override object StringToObject(String xml)
 		{
 			if (string.Equals(TrueString, xml, StringComparison.InvariantCultureIgnoreCase))
 			{
-				return true;
+				return TrueObject;
 			}
 			else if (string.Equals(FalseString, xml, StringComparison.InvariantCultureIgnoreCase))
 			{
-				return false;
+				return FalseObject;
 			}
 			else
 			{