From f4b45eb5a9085577ecacbfe82a2bc5eb31470863 Mon Sep 17 00:00:00 2001
From: Lukasz Antoniak <lukasz.antoniak@gmail.com>
Date: Fri, 1 Feb 2013 15:17:30 +0100
Subject: [PATCH] HHH-2045 - HQL empty IN list

---
 hibernate-core/src/main/antlr/hql.g           |  1 +
 .../ast/tree/InLogicOperatorNode.java         |  6 ++--
 .../test/hql/ASTParserLoadingTest.java        | 29 +++++++++++++++++++
 .../java/org/hibernate/test/hql/HQLTest.java  |  2 +-
 4 files changed, 35 insertions(+), 3 deletions(-)

diff --git a/hibernate-core/src/main/antlr/hql.g b/hibernate-core/src/main/antlr/hql.g
index 7ebc79e4ac..90aca2aedd 100644
--- a/hibernate-core/src/main/antlr/hql.g
+++ b/hibernate-core/src/main/antlr/hql.g
@@ -758,6 +758,7 @@ collectionExpr
 compoundExpr
 	: collectionExpr
 	| path
+	| { LA(1) == OPEN && LA(2) == CLOSE }? OPEN! CLOSE!
 	| (OPEN! ( (expression (COMMA! expression)*) | subQuery ) CLOSE!)
 	| parameter
 	;
diff --git a/hibernate-core/src/main/java/org/hibernate/hql/internal/ast/tree/InLogicOperatorNode.java b/hibernate-core/src/main/java/org/hibernate/hql/internal/ast/tree/InLogicOperatorNode.java
index 6bb5e12421..f17dbada6e 100644
--- a/hibernate-core/src/main/java/org/hibernate/hql/internal/ast/tree/InLogicOperatorNode.java
+++ b/hibernate-core/src/main/java/org/hibernate/hql/internal/ast/tree/InLogicOperatorNode.java
@@ -79,7 +79,9 @@ public class InLogicOperatorNode extends BinaryLogicOperatorNode implements Bina
         if ( !isNodeAcceptable( rhsNode ) )
             return;
         int rhsColumnSpan = 0;
-        if ( rhsNode.getType() == HqlTokenTypes.VECTOR_EXPR ) {
+        if ( rhsNode == null ) {
+            return; // early exit for empty IN list
+        } else if ( rhsNode.getType() == HqlTokenTypes.VECTOR_EXPR ) {
             rhsColumnSpan = rhsNode.getNumberOfChildren();
         } else {
             Type rhsType = extractDataType( rhsNode );
@@ -96,7 +98,7 @@ public class InLogicOperatorNode extends BinaryLogicOperatorNode implements Bina
 	 * this is possible for parameter lists and explicit lists. It is completely unreasonable for sub-queries.
 	 */
     private boolean isNodeAcceptable( Node rhsNode ) {
-        return rhsNode instanceof LiteralNode
+        return rhsNode == null /* empty IN list */ || rhsNode instanceof LiteralNode
                 || rhsNode instanceof ParameterNode
                 || rhsNode.getType() == HqlTokenTypes.VECTOR_EXPR;
     }
diff --git a/hibernate-core/src/test/java/org/hibernate/test/hql/ASTParserLoadingTest.java b/hibernate-core/src/test/java/org/hibernate/test/hql/ASTParserLoadingTest.java
index e886792144..49c94e6cd0 100644
--- a/hibernate-core/src/test/java/org/hibernate/test/hql/ASTParserLoadingTest.java
+++ b/hibernate-core/src/test/java/org/hibernate/test/hql/ASTParserLoadingTest.java
@@ -49,6 +49,7 @@ import org.hibernate.TypeMismatchException;
 import org.hibernate.cfg.Configuration;
 import org.hibernate.cfg.Environment;
 import org.hibernate.dialect.DB2Dialect;
+import org.hibernate.dialect.H2Dialect;
 import org.hibernate.dialect.HSQLDialect;
 import org.hibernate.dialect.IngresDialect;
 import org.hibernate.dialect.MySQLDialect;
@@ -77,6 +78,7 @@ import org.hibernate.test.cid.Order;
 import org.hibernate.test.cid.Product;
 import org.hibernate.testing.DialectChecks;
 import org.hibernate.testing.FailureExpected;
+import org.hibernate.testing.RequiresDialect;
 import org.hibernate.testing.RequiresDialectFeature;
 import org.hibernate.testing.SkipForDialect;
 import org.hibernate.testing.TestForIssue;
@@ -485,6 +487,33 @@ public class ASTParserLoadingTest extends BaseCoreFunctionalTestCase {
 		s.close();
 	}
 
+	@Test
+	@TestForIssue( jiraKey = "HHH-2045" )
+	@RequiresDialect( H2Dialect.class )
+	public void testEmptyInList() {
+		Session session = openSession();
+		session.beginTransaction();
+		Human human = new Human();
+		human.setName( new Name( "Lukasz", null, "Antoniak" ) );
+		human.setNickName( "NONE" );
+		session.save( human );
+		session.getTransaction().commit();
+		session.close();
+
+		session = openSession();
+		session.beginTransaction();
+		List results = session.createQuery( "from Human h where h.nickName in ()" ).list();
+		assertEquals( 0, results.size() );
+		session.getTransaction().commit();
+		session.close();
+
+		session = openSession();
+		session.beginTransaction();
+		session.delete( human );
+		session.getTransaction().commit();
+		session.close();
+	}
+
 	@Test
 	public void testComponentNullnessChecks() {
 		Session s = openSession();
diff --git a/hibernate-core/src/test/java/org/hibernate/test/hql/HQLTest.java b/hibernate-core/src/test/java/org/hibernate/test/hql/HQLTest.java
index ddda76c903..7896818b19 100644
--- a/hibernate-core/src/test/java/org/hibernate/test/hql/HQLTest.java
+++ b/hibernate-core/src/test/java/org/hibernate/test/hql/HQLTest.java
@@ -245,7 +245,7 @@ public class HQLTest extends QueryTranslatorTestCase {
 	}
 
 	@Test
-	@FailureExpected( jiraKey = "N/A" )
+	@TestForIssue( jiraKey = "HHH-2045" )
 	public void testEmptyInList() {
 		assertTranslation( "select a from Animal a where a.description in ()" );
 	}