Improvement to projection list syntax in QueryOver.

(Thanks to maciejk for suggesting improvement in NH-Forge blog reply)

SVN: trunk@4921

Author: FlukeFan

src/NHibernate.Test/Criteria/Lambda/IntegrationFixture.cs

@@ -231,9 +231,7 @@ public void SubQuery()
 
 				QueryOver<Child> averageChildAge =
 					QueryOver.Of<Child>()
-						.SelectList
-							.SelectAvg(c => c.Age)
-							.EndSelect;
+						.Select(p => p.SelectAvg(c => c.Age));
 
 				QueryOver<Child> childCountQuery =
 					QueryOver.Of<Child>()
@@ -243,11 +241,10 @@ public void SubQuery()
 				var nameAndChildCount =
 					s.QueryOver<Person>(() => personAlias)
 						.WithSubquery.Where(p => p.Age <= averageChildAge.As<int>())
-						.SelectList
+						.Select(list => list
 							.Select(p => p.Name)
-							.SelectSubQuery(childCountQuery).WithAlias(() => childCountAlias)
-							.EndSelect
-							.OrderBy(() => childCountAlias).Desc
+							.SelectSubQuery(childCountQuery).WithAlias(() => childCountAlias))
+						.OrderBy(() => childCountAlias).Desc
 						.List<object[]>()
 						.Select(props => new {
 							Name = (string)props[0],

src/NHibernate.Test/Criteria/Lambda/ProjectionsFixture.cs

@@ -114,7 +114,7 @@ public void InlineProjectionList()
 			Person personAgeProjectionAlias = null;
 			var actual =
 				CreateTestQueryOver<Person>(() => personAlias)
-					.SelectList
+					.Select(list => list
 						.SelectAvg(p => p.Age).WithAlias(() => personAgeProjectionAlias)
 						.Select(Projections.Avg("Age")) // allows private properties
 						.SelectAvg(() => personAlias.Age)
@@ -132,8 +132,7 @@ public void InlineProjectionList()
 						.Select(() => personAlias.Age)
 						.SelectSubQuery(DetachedQueryOverAge)
 						.SelectSum(p => p.Age)
-						.SelectSum(() => personAlias.Age)
-						.EndSelect;
+						.SelectSum(() => personAlias.Age));
 
 			AssertCriteriaAreEqual(expected, actual);
 		}

src/NHibernate/Criterion/Lambda/QueryOverProjectionBuilder.cs

@@ -9,18 +9,14 @@
 namespace NHibernate.Criterion.Lambda
 {
 
-	public class QueryOverProjectionBuilder<TReturn, TRoot, TSubType>
+	public class QueryOverProjectionBuilder<T>
 	{
 
-		private TReturn fluentReturn;
-		private IQueryOver<TRoot,TSubType> criteria;
 		private ProjectionList projectionList;
 		private IProjection lastProjection = null;
 
-		public QueryOverProjectionBuilder(TReturn fluentReturn, IQueryOver<TRoot,TSubType> criteria)
+		public QueryOverProjectionBuilder()
 		{
-			this.fluentReturn = fluentReturn;
-			this.criteria = criteria;
 			projectionList = Projections.ProjectionList();
 		}
 
@@ -36,23 +32,19 @@ private void PushProjection(IProjection projection)
 			lastProjection = projection;
 		}
 
-		/// <summary>
-		/// Create the ProjectionList and return to the query
-		/// </summary>
-		public TReturn EndSelect
+		internal ProjectionList ProjectionList
 		{
 			get
 			{
 				AddLastProjection();
-				criteria.Select(projectionList);
-				return fluentReturn;
+				return projectionList;
 			}
 		}
 
 		/// <summary>
 		/// Create an alias for the previous projection
 		/// </summary>
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> WithAlias(Expression<Func<object>> alias)
+		public QueryOverProjectionBuilder<T> WithAlias(Expression<Func<object>> alias)
 		{
 			string aliasContainer = ExpressionProcessor.FindMemberExpression(alias.Body);
 			lastProjection = Projections.Alias(lastProjection, aliasContainer);
@@ -62,7 +54,7 @@ public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> WithAlias(Expression
 		/// <summary>
 		/// Select an arbitrary projection
 		/// </summary>
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> Select(IProjection projection)
+		public QueryOverProjectionBuilder<T> Select(IProjection projection)
 		{
 			PushProjection(projection);
 			return this;
@@ -71,7 +63,7 @@ public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> Select(IProjection p
 		/// <summary>
 		/// A property average value
 		/// </summary>
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectAvg(Expression<Func<TSubType, object>> expression)
+		public QueryOverProjectionBuilder<T> SelectAvg(Expression<Func<T, object>> expression)
 		{
 			PushProjection(Projections.Avg(expression));
 			return this;
@@ -80,7 +72,7 @@ public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectAvg(Expression
 		/// <summary>
 		/// A property average value
 		/// </summary>
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectAvg(Expression<Func<object>> expression)
+		public QueryOverProjectionBuilder<T> SelectAvg(Expression<Func<object>> expression)
 		{
 			PushProjection(Projections.Avg(expression));
 			return this;
@@ -89,7 +81,7 @@ public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectAvg(Expression
 		/// <summary>
 		/// A property value count
 		/// </summary>
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectCount(Expression<Func<TSubType, object>> expression)
+		public QueryOverProjectionBuilder<T> SelectCount(Expression<Func<T, object>> expression)
 		{
 			PushProjection(Projections.Count(expression));
 			return this;
@@ -98,7 +90,7 @@ public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectCount(Expressi
 		/// <summary>
 		/// A property value count
 		/// </summary>
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectCount(Expression<Func<object>> expression)
+		public QueryOverProjectionBuilder<T> SelectCount(Expression<Func<object>> expression)
 		{
 			PushProjection(Projections.Count(expression));
 			return this;
@@ -107,7 +99,7 @@ public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectCount(Expressi
 		/// <summary>
 		/// A distinct property value count
 		/// </summary>
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectCountDistinct(Expression<Func<TSubType, object>> expression)
+		public QueryOverProjectionBuilder<T> SelectCountDistinct(Expression<Func<T, object>> expression)
 		{
 			PushProjection(Projections.CountDistinct(expression));
 			return this;
@@ -116,7 +108,7 @@ public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectCountDistinct(
 		/// <summary>
 		/// A distinct property value count
 		/// </summary>
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectCountDistinct(Expression<Func<object>> expression)
+		public QueryOverProjectionBuilder<T> SelectCountDistinct(Expression<Func<object>> expression)
 		{
 			PushProjection(Projections.CountDistinct(expression));
 			return this;
@@ -125,7 +117,7 @@ public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectCountDistinct(
 		/// <summary>
 		/// A grouping property value
 		/// </summary>
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectGroup(Expression<Func<TSubType, object>> expression)
+		public QueryOverProjectionBuilder<T> SelectGroup(Expression<Func<T, object>> expression)
 		{
 			PushProjection(Projections.Group(expression));
 			return this;
@@ -134,7 +126,7 @@ public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectGroup(Expressi
 		/// <summary>
 		/// A grouping property value
 		/// </summary>
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectGroup(Expression<Func<object>> expression)
+		public QueryOverProjectionBuilder<T> SelectGroup(Expression<Func<object>> expression)
 		{
 			PushProjection(Projections.Group(expression));
 			return this;
@@ -143,7 +135,7 @@ public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectGroup(Expressi
 		/// <summary>
 		/// A property maximum value
 		/// </summary>
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectMax(Expression<Func<TSubType, object>> expression)
+		public QueryOverProjectionBuilder<T> SelectMax(Expression<Func<T, object>> expression)
 		{
 			PushProjection(Projections.Max(expression));
 			return this;
@@ -152,7 +144,7 @@ public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectMax(Expression
 		/// <summary>
 		/// A property maximum value
 		/// </summary>
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectMax(Expression<Func<object>> expression)
+		public QueryOverProjectionBuilder<T> SelectMax(Expression<Func<object>> expression)
 		{
 			PushProjection(Projections.Max(expression));
 			return this;
@@ -161,7 +153,7 @@ public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectMax(Expression
 		/// <summary>
 		/// A property minimum value
 		/// </summary>
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectMin(Expression<Func<TSubType, object>> expression)
+		public QueryOverProjectionBuilder<T> SelectMin(Expression<Func<T, object>> expression)
 		{
 			PushProjection(Projections.Min(expression));
 			return this;
@@ -170,7 +162,7 @@ public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectMin(Expression
 		/// <summary>
 		/// A property minimum value
 		/// </summary>
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectMin(Expression<Func<object>> expression)
+		public QueryOverProjectionBuilder<T> SelectMin(Expression<Func<object>> expression)
 		{
 			PushProjection(Projections.Min(expression));
 			return this;
@@ -179,7 +171,7 @@ public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectMin(Expression
 		/// <summary>
 		/// A projected property value
 		/// </summary>
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> Select(Expression<Func<TSubType, object>> expression)
+		public QueryOverProjectionBuilder<T> Select(Expression<Func<T, object>> expression)
 		{
 			PushProjection(Projections.Property(expression));
 			return this;
@@ -188,13 +180,13 @@ public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> Select(Expression<Fu
 		/// <summary>
 		/// A projected property value
 		/// </summary>
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> Select(Expression<Func<object>> expression)
+		public QueryOverProjectionBuilder<T> Select(Expression<Func<object>> expression)
 		{
 			PushProjection(Projections.Property(expression));
 			return this;
 		}
 
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectSubQuery<U>(QueryOver<U> detachedQueryOver)
+		public QueryOverProjectionBuilder<T> SelectSubQuery<U>(QueryOver<U> detachedQueryOver)
 		{
 			PushProjection(Projections.SubQuery(detachedQueryOver));
 			return this;
@@ -203,7 +195,7 @@ public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectSubQuery<U>(Qu
 		/// <summary>
 		/// A property value sum
 		/// </summary>
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectSum(Expression<Func<TSubType, object>> expression)
+		public QueryOverProjectionBuilder<T> SelectSum(Expression<Func<T, object>> expression)
 		{
 			PushProjection(Projections.Sum(expression));
 			return this;
@@ -212,7 +204,7 @@ public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectSum(Expression
 		/// <summary>
 		/// A property value sum
 		/// </summary>
-		public QueryOverProjectionBuilder<TReturn, TRoot, TSubType> SelectSum(Expression<Func<object>> expression)
+		public QueryOverProjectionBuilder<T> SelectSum(Expression<Func<object>> expression)
 		{
 			PushProjection(Projections.Sum(expression));
 			return this;

src/NHibernate/Criterion/QueryOver.cs

@@ -264,9 +264,10 @@ public QueryOver<TRoot,TSubType> Select(params IProjection[] projections)
 			return this;
 		}
 
-		public QueryOverProjectionBuilder<QueryOver<TRoot,TSubType>, TRoot, TSubType> SelectList
+		public QueryOver<TRoot, TSubType> Select(Func<QueryOverProjectionBuilder<TSubType>, QueryOverProjectionBuilder<TSubType>> list)
 		{
-			get { return new QueryOverProjectionBuilder<QueryOver<TRoot,TSubType>, TRoot, TSubType>(this, this); }
+			criteria.SetProjection(list(new QueryOverProjectionBuilder<TSubType>()).ProjectionList);
+			return this;
 		}
 
 		public QueryOverOrderBuilder<TRoot,TSubType> OrderBy(Expression<Func<TSubType, object>> path)
@@ -604,8 +605,8 @@ IQueryOver<TRoot,TSubType> IQueryOver<TRoot,TSubType>.Select(params Expression<F
 		IQueryOver<TRoot,TSubType> IQueryOver<TRoot,TSubType>.Select(params IProjection[] projections)
 		{ return Select(projections); }
 
-		QueryOverProjectionBuilder<IQueryOver<TRoot,TSubType>, TRoot, TSubType> IQueryOver<TRoot,TSubType>.SelectList
-		{ get { return new QueryOverProjectionBuilder<IQueryOver<TRoot,TSubType>,TRoot,TSubType>(this, this); } }
+		IQueryOver<TRoot, TSubType> IQueryOver<TRoot, TSubType>.Select(Func<QueryOverProjectionBuilder<TSubType>, QueryOverProjectionBuilder<TSubType>> list)
+		{ return Select(list); }
 
 		IQueryOverOrderBuilder<TRoot,TSubType> IQueryOver<TRoot,TSubType>.OrderBy(Expression<Func<TSubType, object>> path)
 		{ return new IQueryOverOrderBuilder<TRoot,TSubType>(this, path); }

src/NHibernate/IQueryOver.cs

@@ -208,9 +208,9 @@ public interface IQueryOver<TRoot,TSubType> : IQueryOver<TRoot>
 		IQueryOver<TRoot,TSubType> Select(params IProjection[] projections);
 
 		/// <summary>
-		/// Create a list of projections inline
+		/// Create a list of projections using a projection builder
 		/// </summary>
-		QueryOverProjectionBuilder<IQueryOver<TRoot,TSubType>, TRoot, TSubType> SelectList { get; }
+		IQueryOver<TRoot, TSubType> Select(Func<QueryOverProjectionBuilder<TSubType>, QueryOverProjectionBuilder<TSubType>> list);
 
 		/// <summary>
 		/// Add order expressed as a lambda expression