Fix IFilter.SetParameterList not supporting HashSet<T> arguments

src/NHibernate.Test/FilterTest/Product.cs

@@ -75,6 +75,8 @@ public virtual ISet<Category> Categories
 			set { categories = value; }
 		}
 
+		public virtual Guid ProductGuid { get; set; }
+
 		public override int GetHashCode()
 		{
 			return stockNumber;

src/NHibernate.Test/FilterTest/classes.hbm.xml

@@ -79,6 +79,8 @@
 		<property name="EffectiveStartDate" column="eff_start_dt" type="Date"/>
 		<property name="EffectiveEndDate" column="eff_end_dt" type="Date"/>
 
+		<property name="ProductGuid"/>
+
 		<set cascade="none" inverse="true" name="OrderLineItems">
 			<key column="PROD_ID"/>
 			<one-to-many class="LineItem"/>
@@ -93,6 +95,7 @@
 		</set>
 
 		<filter name="effectiveDate" condition=":asOfDate BETWEEN eff_start_dt and eff_end_dt"/>
+		<filter name="guidlist" condition="ProductGuid IN (:guids)"/>
 	</class>
 
 	<class name="Salesperson" table="SALES_PERSON">
@@ -118,4 +121,4 @@
 		<filter name="regionlist" condition="REG IN (:regions)"/>
 	</class>
 
-</hibernate-mapping>
+</hibernate-mapping>

src/NHibernate.Test/FilterTest/defs.hbm.xml

@@ -24,4 +24,8 @@
 	<filter-def name="cat">
 		<filter-param name="catId" type="long"/>
 	</filter-def>
-</hibernate-mapping>
+
+	<filter-def name="guidlist">
+		<filter-param name="guids" type="guid"/>
+	</filter-def>
+</hibernate-mapping>

src/NHibernate/Engine/Query/NativeSQLQueryPlan.cs

@@ -151,19 +151,16 @@ private SqlString ExpandDynamicFilterParameters(SqlString sqlString, ICollection
 						string parameterName = parts[1];
 						var filter = (FilterImpl)enabledFilters[filterName];
 
-						object value = filter.GetParameter(parameterName);
+						var collectionSpan = filter.GetParameterSpan(parameterName);
 						IType type = filter.FilterDefinition.GetParameterType(parameterName);
 						int parameterColumnSpan = type.GetColumnSpan(session.Factory);
-						var collectionValue = value as ICollection;
-						int? collectionSpan = null;
 
 						// Add query chunk
-						string typeBindFragment = string.Join(", ", Enumerable.Repeat("?", parameterColumnSpan).ToArray());
+						string typeBindFragment = string.Join(", ", Enumerable.Repeat("?", parameterColumnSpan));
 						string bindFragment;
-						if (collectionValue != null && !type.ReturnedClass.IsArray)
+						if (collectionSpan.HasValue && !type.ReturnedClass.IsArray)
 						{
-							collectionSpan = collectionValue.Count;
-							bindFragment = string.Join(", ", Enumerable.Repeat(typeBindFragment, collectionValue.Count).ToArray());
+							bindFragment = string.Join(", ", Enumerable.Repeat(typeBindFragment, collectionSpan.Value));
 						}
 						else
 						{

src/NHibernate/Impl/FilterImpl.cs

@@ -16,6 +16,7 @@ public class FilterImpl : IFilter
 		private FilterDefinition definition;
 
 		private readonly IDictionary<string, object> parameters = new Dictionary<string, object>();
+		private readonly Dictionary<string, int> _parameterSpans = new Dictionary<string, int>();
 
 		public void AfterDeserialize(FilterDefinition factoryDefinition)
 		{
@@ -75,20 +76,21 @@ public IFilter SetParameter(string name, object value)
 		/// <param name="name">The parameter's name.</param>
 		/// <param name="values">The values to be expanded into an SQL IN list.</param>
 		/// <returns>This FilterImpl instance (for method chaining).</returns>
+		/// <exception cref="ArgumentNullException">Thrown when <paramref name="name"/> or <paramref name="values"/> are <see langword="null" />.</exception>
 		public IFilter SetParameterList<T>(string name, ICollection<T> values)
 		{
+			if (values == null)
+				throw new ArgumentNullException(nameof(values), "Collection must be not null!");
+
 			var type = definition.GetParameterType(name);
 			if (type == null)
-			{
 				throw new HibernateException("Undefined filter parameter [" + name + "]");
-			}
 
 			if (!type.ReturnedClass.IsAssignableFrom(typeof(T)))
-			{
 				throw new HibernateException("Incorrect type for parameter [" + name + "]");
-			}
 
-			parameters[name] = values ?? throw new ArgumentException("Collection must be not null!", nameof(values));
+			_parameterSpans[name] = values.Count;
+			parameters[name] = values;
 			return this;
 		}
 
@@ -99,6 +101,18 @@ public object GetParameter(string name)
 			return result;
 		}
 
+		/// <summary>
+		/// Get the span of a value list parameter by name. <see langword="null" /> if the parameter is not a value list
+		/// or if there is no such parameter.
+		/// </summary>
+		/// <param name="name">The parameter name.</param>
+		/// <returns>The parameter span, or <see langword="null" /> if the parameter is not a value list or
+		/// if there is no such parameter.</returns>
+		public int? GetParameterSpan(string name)
+		{
+			return _parameterSpans.TryGetValue(name, out var result) ? result : default(int?);
+		}
+
 		/// <summary>
 		/// Perform validation of the filter state.  This is used to verify the
 		/// state of the filter after its enablement and before its use.

src/NHibernate/Loader/Loader.cs

@@ -1859,19 +1859,16 @@ protected SqlString ExpandDynamicFilterParameters(SqlString sqlString, ICollecti
 						string parameterName = parts[1];
 						var filter = (FilterImpl)enabledFilters[filterName];
 
-						object value = filter.GetParameter(parameterName);
+						int? collectionSpan = filter.GetParameterSpan(parameterName);
 						IType type = filter.FilterDefinition.GetParameterType(parameterName);
 						int parameterColumnSpan = type.GetColumnSpan(session.Factory);
-						var collectionValue = value as ICollection;
-						int? collectionSpan = null;
 
 						// Add query chunk
-						string typeBindFragment = string.Join(", ", Enumerable.Repeat("?", parameterColumnSpan).ToArray());
+						string typeBindFragment = string.Join(", ", Enumerable.Repeat("?", parameterColumnSpan));
 						string bindFragment;
-						if (collectionValue != null && !type.ReturnedClass.IsArray)
+						if (collectionSpan.HasValue && !type.ReturnedClass.IsArray)
 						{
-							collectionSpan = collectionValue.Count;
-							bindFragment = string.Join(", ", Enumerable.Repeat(typeBindFragment, collectionValue.Count).ToArray());
+							bindFragment = string.Join(", ", Enumerable.Repeat(typeBindFragment, collectionSpan.Value));
 						}
 						else
 						{