HHH-16609 SQLFunctionRegistry#findSQLFunction needs to guard against null argument

Author: Sanne

hibernate-core/src/main/java/org/hibernate/dialect/function/SQLFunctionRegistry.java

@@ -39,9 +39,12 @@ public SQLFunctionRegistry(Dialect dialect, Map<String, SQLFunction> userFunctio
 	 *
 	 * @param functionName The name of the function to locate
 	 *
-	 * @return The located function, maye return {@code null}
+	 * @return The located function, may return {@code null}
 	 */
-	public SQLFunction findSQLFunction(String functionName) {
+	public SQLFunction findSQLFunction(final String functionName) {
+		if ( functionName == null ) {
+			return null;
+		}
 		return functionMap.get( functionName );
 	}
 

hibernate-core/src/test/java/org/hibernate/sql/TemplateTest.java

@@ -107,6 +107,12 @@ public static void closeSessionFactory() {
 		}
 	}
 
+	@Test
+	public void testNullToFunction() {
+		//Apparently this may happen during HQL parsing given a wrong syntax
+		FUNCTION_REGISTRY.findSQLFunction( null );
+	}
+
 	@Test
 	public void testSqlExtractFunction() {
 		String fragment = "extract( year from col )";