test: DataSource.getConnection().unwrap(PGConnection.class)

fixes #573

pgjdbc/src/test/java/org/postgresql/test/jdbc4/WrapperTest.java

@@ -10,6 +10,7 @@
 
 import org.postgresql.PGConnection;
 import org.postgresql.PGStatement;
+import org.postgresql.ds.PGSimpleDataSource;
 import org.postgresql.test.TestUtil;
 
 import junit.framework.TestCase;
@@ -75,6 +76,19 @@ public void testConnectionUnwrapPGConnection() throws SQLException {
     assertTrue(v instanceof PGConnection);
   }
 
+  public void testConnectionUnwrapPGDataSource() throws SQLException {
+    PGSimpleDataSource dataSource = new PGSimpleDataSource();
+    dataSource.setDatabaseName(TestUtil.getDatabase());
+    dataSource.setServerName(TestUtil.getServer());
+    dataSource.setPortNumber(TestUtil.getPort());
+    Connection connection = dataSource.getConnection(TestUtil.getUser(), TestUtil.getPassword());
+    assertNotNull("Unable to obtain a connection from PGSimpleDataSource", connection);
+    Object v = connection.unwrap(PGConnection.class);
+    assertTrue("connection.unwrap(PGConnection.class) should return PGConnection instance"
+            + ", actual instance is " + v,
+        v instanceof PGConnection);
+  }
+
   public void testStatementIsWrapperForPrivate() throws SQLException {
     assertFalse(_statement.isWrapperFor(PrivateInterface.class));
   }