add testcase & bug fixed for DruidConnectionHolderInitError

src/test/java/com/alibaba/druid/bvt/pool/DruidConnectionHolderTest3.java

@@ -0,0 +1,62 @@
+package com.alibaba.druid.bvt.pool;
+
+import java.sql.SQLException;
+
+import junit.framework.Assert;
+import junit.framework.TestCase;
+
+import com.alibaba.druid.filter.FilterAdapter;
+import com.alibaba.druid.filter.FilterChain;
+import com.alibaba.druid.pool.DruidDataSource;
+import com.alibaba.druid.pool.GetConnectionTimeoutException;
+import com.alibaba.druid.proxy.jdbc.ConnectionProxy;
+
+public class DruidConnectionHolderTest3 extends TestCase {
+
+    private DruidDataSource dataSource;
+
+    protected void setUp() throws Exception {
+        dataSource = new DruidDataSource();
+        dataSource.setUrl("jdbc:mock:xxx");
+        dataSource.setTestOnBorrow(false);
+        dataSource.setInitialSize(1);
+        dataSource.getProxyFilters().add(new FilterAdapter() {
+
+            public int connection_getTransactionIsolation(FilterChain chain, ConnectionProxy connection)
+                                                                                                        throws SQLException {
+                throw new MySQLException();
+            }
+        });
+
+    }
+
+    protected void tearDown() throws Exception {
+        dataSource.close();
+    }
+
+    public void test_mysqlSyntaxError() throws Exception {
+        {
+            Exception error = null;
+            try {
+                dataSource.init();
+            } catch (MySQLException e) {
+                error = e;
+            }
+            Assert.assertNotNull(error);
+        }
+
+        Assert.assertEquals(0, dataSource.getPoolingCount());
+
+        Exception error = null;
+        try {
+            dataSource.getConnection(100);
+        } catch (GetConnectionTimeoutException e) {
+            error = e;
+        }
+        Assert.assertNotNull(error);
+    }
+
+    public static class MySQLException extends SQLException {
+
+    }
+}