FIX: subquery could not not have a where clause

ebean-core/src/main/java/io/ebeaninternal/server/query/CQueryPredicates.java

@@ -22,6 +22,7 @@ import java.sql.Connection;
 import java.sql.PreparedStatement;
 import java.sql.SQLException;
 import java.sql.Timestamp;
+import java.util.Collections;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
@@ -411,7 +412,7 @@ public class CQueryPredicates {
    * Return the bind values for the where expression.
    */
   public List<Object> getWhereExprBindValues() {
-    return where.getBindValues();
+    return where == null ? Collections.emptyList() : where.getBindValues();
   }
 
   /**

ebean-core/src/test/java/org/tests/query/TestQueryExists.java

@@ -4,7 +4,6 @@ import io.ebean.BaseTestCase;
 import io.ebean.Ebean;
 import io.ebean.Query;
 import io.ebeantest.LoggedSql;
-
 import org.junit.Test;
 import org.tests.model.basic.Customer;
 import org.tests.model.basic.Order;
@@ -111,4 +110,17 @@ public class TestQueryExists extends BaseTestCase {
 
     assertThat(sql).contains("not exists (");
   }
+
+  @Test
+  public void testExistsNoWhere() {
+    ResetBasicData.reset();
+
+    Query<Order> subQuery = Ebean.find(Order.class).alias("sq").select("id");
+    Query<Customer> query = Ebean.find(Customer.class).alias("qt").where().notExists(subQuery).query();
+
+    query.findList();
+    String sql = query.getGeneratedSql();
+
+    assertThat(sql).contains("not exists (select sq.id from o_order sq)");
+  }
 }

ebean-core/src/test/java/org/tests/query/TestSubQuery.java

@@ -44,7 +44,17 @@ public class TestSubQuery extends BaseTestCase {
     Query<Order> sq = DB.createQuery(Order.class).select("id").where()
       .isIn("details.product.id", productIds).query();
 
-    DB.find(Order.class).where().isIn("id", sq).findList();
+    assertThat(DB.find(Order.class).where().isIn("id", sq).findList()).hasSize(2);
+  }
+
+  @Test
+  public void test_IsInNoWhere() {
+    ResetBasicData.reset();
+
+    Query<Order> sq = DB.createQuery(Order.class).select("id");
+    int expectedSize = DB.find(Order.class).findCount(); // expect everything
+
+    assertThat(DB.find(Order.class).where().isIn("id", sq).findList()).hasSize(expectedSize);
   }
 
   public void testCompositeKey() {