Junit 5 : AssertionFailedError: expected: <true> but was: <false>

Question

我正在尝试为服务中的以下功能编写单元测试用例 class

@Service
    public class currencyHandler {
        public boolean isNoDecimal(String currency) {
            return "JPY".equalsIgnoreCase(currency) || "KRW".equalsIgnoreCase(currency);
        }
    }

单位案例如下：

    import org.junit.jupiter.api.Test;
    import static org.junit.jupiter.api.Assertions.assertFalse;
    import static org.junit.jupiter.api.Assertions.assertTrue;
    import org.springframework.test.context.junit.jupiter.SpringExtension;
    import org.svc.it.handlers;
    
    @ExtendWith(SpringExtension.class)
    public class CurrencyTests {
    
        @Mock
        CurrencyHandler currencyHandlerTest;
    
        @Test
        public void isNoCurrency() throws Exception {
            assertTrue(currencyHandlerTest.isNoCurrency("ABC"));
            assertTrue(currencyHandlerTest.isNoCurrency("XYZ"));
            assertFalse(currencyHandlerTest.isNoCurrency("BOGUS"));
            assertFalse(currencyHandlerTest.isNoCurrency(""));
            assertFalse(currencyHandlerTest.isNoCurrency(null));
        }
    }

下面是我运行上面的单元测试用例时的错误：

org.opentest4j.AssertionFailedError: expected: <true> but was: <false>
    at org.junit.jupiter.api.AssertionUtils.fail(AssertionUtils.java:55)
    at org.junit.jupiter.api.AssertTrue.assertTrue(AssertTrue.java:40)
    at org.junit.jupiter.api.AssertTrue.assertTrue(AssertTrue.java:35)
    at org.junit.jupiter.api.Assertions.assertTrue(Assertions.java:162)

我想我对@Mock 对象做错了什么。感谢你的帮助。提前致谢！

Answer 1

要为 CurrencyHandler class 编写单元测试，您必须针对 class 的一个实例进行测试。您不得针对 class.

的 mock 实例进行测试

下面展示了如何编写这样的单元测试。

package example;

import org.junit.jupiter.api.Test;

import static org.junit.jupiter.api.Assertions.assertFalse;
import static org.junit.jupiter.api.Assertions.assertTrue;

class CurrencyHandlerTests {

    private CurrencyHandler currencyHandler = new CurrencyHandler();

    @Test
    void isNoDecimal() {
        assertTrue(currencyHandler.isNoDecimal("JPY"));
        assertTrue(currencyHandler.isNoDecimal("KRW"));
        assertFalse(currencyHandler.isNoDecimal("BOGUS"));
        assertFalse(currencyHandler.isNoDecimal(""));
        assertFalse(currencyHandler.isNoDecimal(null));
    }
}

为了更好地理解这里的概念，我建议您阅读一些关于单元测试、模拟和 SUT（被测对象）的文章或书籍。

另外，如果你写的是像上面那样的纯单元测试，你不需要注册SpringExtension，因为纯单元测试不需要与[=27中的组件进行交互=] ApplicationContext.

Junit 5 : AssertionFailedError: expected: <true> but was: <false>

Junit 5 : AssertionFailedError: expected: <true> but was: <false>

exception

junit

assert

junit5