NH-3727 - Fix re-using Criteria with SubqueryProjection

Author: hazzik

src/NHibernate/Criterion/SubqueryExpression.cs

@@ -20,10 +20,8 @@ public abstract class SubqueryExpression : AbstractCriterion
 private QueryParameters parameters;
 private IType[] types;
 
-[NonSerialized] private CriteriaQueryTranslator innerQuery;
-
 protected SubqueryExpression(String op, String quantifier, DetachedCriteria dc)
-:this(op, quantifier, dc, true)
+: this(op, quantifier, dc, true)
 {
 }
 
@@ -44,16 +42,23 @@ public IType[] GetTypes()
 
 public override SqlString ToSqlString(ICriteria criteria, ICriteriaQuery criteriaQuery, IDictionary<string, IFilter> enabledFilters)
 {
-InitializeInnerQueryAndParameters(criteriaQuery);
+ISessionFactoryImplementor factory = criteriaQuery.Factory;
+
+var innerQuery = new CriteriaQueryTranslator(
+factory,
+criteriaImpl, //implicit polymorphism not supported (would need a union)
+criteriaImpl.EntityOrClassName,
+criteriaQuery.GenerateSQLAlias(),
+criteriaQuery);
+
+types = innerQuery.HasProjection ? innerQuery.ProjectedTypes : null;
 
 if (innerQuery.HasProjection == false)
 {
 throw new QueryException("Cannot use subqueries on a criteria without a projection.");
 }
 
-ISessionFactoryImplementor factory = criteriaQuery.Factory;
-
-IOuterJoinLoadable persister = (IOuterJoinLoadable)factory.GetEntityPersister(criteriaImpl.EntityOrClassName);
+IOuterJoinLoadable persister = (IOuterJoinLoadable) factory.GetEntityPersister(criteriaImpl.EntityOrClassName);
 
 //patch to generate joins on subqueries
 //stolen from CriteriaLoader
@@ -73,11 +78,6 @@ public override SqlString ToSqlString(ICriteria criteria, ICriteriaQuery criteri
 sql = factory.Dialect.GetLimitString(sql, offset, limit, offsetParameter, limitParameter);
 }
 
-// during CriteriaImpl.Clone we are doing a shallow copy of each criterion.
-// this is not a problem for common criterion but not for SubqueryExpression because here we are holding the state of inner CriteriaTraslator (ICriteriaQuery).
-// After execution (ToSqlString) we have to clean the internal state because the next execution may be performed in a different tree reusing the same istance of SubqueryExpression.
-innerQuery = null;
-
 SqlStringBuilder buf = new SqlStringBuilder().Add(ToLeftSqlString(criteria, criteriaQuery));
 if (op != null)
 {
@@ -88,7 +88,7 @@ public override SqlString ToSqlString(ICriteria criteria, ICriteriaQuery criteri
 {
 buf.Add(quantifier).Add(" ");
 }
-
+
 buf.Add("(").Add(sql).Add(")");
 
 if (quantifier != null && prefixOp == false)
@@ -101,9 +101,9 @@ public override SqlString ToSqlString(ICriteria criteria, ICriteriaQuery criteri
 
 public override string ToString()
 {
-if(prefixOp)
+if (prefixOp)
 return string.Format("{0} {1} ({2})", op, quantifier, criteriaImpl);
-
+
 return string.Format("{0} ({1}) {2}", op, criteriaImpl, quantifier);
 }
 
@@ -117,23 +117,6 @@ public override IProjection[] GetProjections()
 return null;
 }
 
-public void InitializeInnerQueryAndParameters(ICriteriaQuery criteriaQuery)
-{
-if (innerQuery == null)
-{
-ISessionFactoryImplementor factory = criteriaQuery.Factory;
-
-innerQuery = new CriteriaQueryTranslator(
-factory,
-criteriaImpl, //implicit polymorphism not supported (would need a union)
-criteriaImpl.EntityOrClassName,
-criteriaQuery.GenerateSQLAlias(),
-criteriaQuery);
-
-types = innerQuery.HasProjection ? innerQuery.ProjectedTypes : null;
-}
-}
-
 public ICriteria Criteria
 {
 // NH-1146

src/NHibernate/Criterion/SubqueryProjection.cs

@@ -13,7 +13,7 @@ namespace NHibernate.Criterion
 [Serializable]
 public class SubqueryProjection : SimpleProjection
 {
-private SelectSubqueryExpression _subQuery;
+private readonly SelectSubqueryExpression _subQuery;
 
 protected internal SubqueryProjection(SelectSubqueryExpression subquery)
 {
@@ -37,14 +37,13 @@ public override bool IsAggregate
 
 public override IType[] GetTypes(ICriteria criteria, ICriteriaQuery criteriaQuery)
 {
-_subQuery.InitializeInnerQueryAndParameters(criteriaQuery);
 return _subQuery.GetTypes();
 }
 
 public override SqlString ToSqlString(ICriteria criteria, int loc, ICriteriaQuery criteriaQuery, IDictionary<string, IFilter> enabledFilters)
 {
-SqlString sqlStringSubquery = _subQuery.ToSqlString(criteria, criteriaQuery, enabledFilters);
-return sqlStringSubquery.Append(new SqlString(new object[] { " as y", loc.ToString(), "_" } ));
+return _subQuery.ToSqlString(criteria, criteriaQuery, enabledFilters)
+.Append(new SqlString(" as y", loc.ToString(), "_"));
 }
 
 public override SqlString ToGroupSqlString(ICriteria criteria, ICriteriaQuery criteriaQuery, IDictionary<string, IFilter> enabledFilters)