如何使用 jmock 设置对模拟调用的返回值的期望？

Question

我正在使用 jmock 运行一些测试。我想确保第三方库在 JDBC API 上正确调用以下序列：

context.checking(new Expectations() {{
    oneOf(connection).prepareStatement("test");
    oneOf(statement).setFetchSize(10);
    oneOf(statement).executeQuery();
}});

connection 对象是这样创建的：

Mockery context = new Mockery();
connection = context.mock(Connection.class);

如何创建statement 对象？这些我都试过了，都不管用：

// This creates an independent PreparedStatement mock, not the one that will be returned
// by the Connection.prepareStatement call
PreparedStatement statement = context.mock(PreparedStatement.class);

// This doesn't return a mock object, which I can pass to the oneOf() method.
PreparedStatement statement = oneOf(connection).prepareStatement("test");

Answer 1

您应该在期望中使用will(returnValue(...)) 来指定结果，如下所示：

context.checking(new Expectations() {{
    oneOf(connection).prepareStatement("test"); will(returnValue(statement));
    // ...
}}

另请参阅JMock cheat sheet。

例如I use in tests of Jaybird:

final PooledConnectionHandler conHandler = context.mock(PooledConnectionHandler.class);
final Statement statement = context.mock(Statement.class);
final Connection connectionProxy = context.mock(Connection.class);
final StatementHandler handler = new StatementHandler(conHandler, statement);

context.checking(new Expectations() {
    {
        oneOf(conHandler).getProxy(); will(returnValue(connectionProxy));
    }
});