testable-mock/docs/zh-cn/doc/troubleshooting.md

自助问题排查

相比Mockito等由开发者手工放置Mock类的做法，TestableMock使用方法名和参数类型匹配自动寻找需Mock的调用。这种机制在带来方便的同时也容易导致对“Mock究竟有没生效”的疑问。

若要排查Mock相关的问题，只需在相应的Mock容器类上添加@MockDiagnose注解，并配置参数值为LogLevel.ENABLE，在运行测试时就会打印出详细的Mock方法替换过程。例如：

class DemoTest {
    @MockDiagnose(LogLevel.ENABLE)
    public static class Mock {
        ...
    }
}

输出日志示例如下：

[DIAGNOSE] Handling test class com/alibaba/testable/demo/basic/DemoMockTest
[DIAGNOSE]   Found 6 test cases
[DIAGNOSE] Handling mock class com/alibaba/testable/demo/basic/DemoMockTest$Mock
[DIAGNOSE]   Found 8 mock methods
[DIAGNOSE] Handling source class com/alibaba/testable/demo/basic/DemoMock
[DIAGNOSE]   Handling method <init>
[DIAGNOSE]   Handling method newFunc
[DIAGNOSE]     Line 19, mock method "createBlackBox" used
[DIAGNOSE]   Handling method outerFunc
[DIAGNOSE]     Line 27, mock method "innerFunc" used
[DIAGNOSE]     Line 27, mock method "staticFunc" used
[DIAGNOSE]   Handling method commonFunc
[DIAGNOSE]     Line 34, mock method "trim" used
[DIAGNOSE]     Line 34, mock method "sub" used
[DIAGNOSE]     Line 34, mock method "startsWith" used
... ...

其中Line XX, mock method "XXX" used日志展示了被测类中所有发生了Mock替换的调用和相应代码行号。

简单排查方法：

• 若没有任何输出，请检查pom.xml或build.gradle配置是否正确引入了TestableMock依赖
• 若只输出了Handling mock class，请检查Mock容器类的名称和位置是否符合规范
• 若只输出了Handling mock class和Handling test class，请检查被测类与测试类是否包路径相同，且名称为"被测类+Test"，或者是否正确的使用了@MockWith注解
• 若输出了Handling source class以及Handling method xxx，但预期的代码行位置没有发生Mock替换，请继续检查Mock方法定义是否未与目标方法匹配

对于上述的最后一种情况（预期Mock未生效），可将日志级别提升到LogLevel.VERBOSE做进一步排查。例如：

class DemoTest {
    @MockDiagnose(LogLevel.VERBOSE)
    public static class Mock {
        ...
    }
}

再次执行单元测试，此时将会打印出所有Mock方法的签名定义，以及被测类中扫描到所有调用的实际方法签名：

[DIAGNOSE] Handling test class com/alibaba/testable/demo/basic/DemoMockTest
[VERBOSE]    Test case "should_mock_new_object"
... ...
[VERBOSE]    Test case "should_set_mock_context"
[DIAGNOSE]   Found 6 test cases
[DIAGNOSE] Handling mock class com/alibaba/testable/demo/basic/DemoMockTest$Mock
[VERBOSE]    Mock constructor "createBlackBox" as "com.alibaba.demo.basic.model.BlackBox(java.lang.String)"
[VERBOSE]    Mock method "innerFunc" as "com.alibaba.demo.basic.DemoMock::innerFunc(java.lang.String) : java.lang.String"
... ...
[VERBOSE]    Mock method "callFromDifferentMethod" as "()Ljava/lang/String;"
[DIAGNOSE]   Found 8 mock methods
[DIAGNOSE] Handling source class com/alibaba/testable/demo/basic/DemoMock
[DIAGNOSE]   Handling method <init>
[VERBOSE]      Line 13, constructing "java.lang.Object()"
[DIAGNOSE]   Handling method newFunc
[VERBOSE]      Line 19, constructing "com.alibaba.demo.basic.model.BlackBox(java.lang.String)"
[DIAGNOSE]     Line 19, mock method "createBlackBox" used
[VERBOSE]      Line 19, invoking "com.alibaba.demo.basic.DemoMockTest$Mock::createBlackBox(java.lang.String) : com.alibaba.demo.basic.model.BlackBox"
[VERBOSE]      Line 20, invoking "com.alibaba.demo.basic.model.BlackBox::get() : java.lang.String"
[DIAGNOSE]   Handling method outerFunc
[VERBOSE]      Line 27, constructing "java.lang.StringBuilder()"
[VERBOSE]      Line 27, invoking "java.lang.StringBuilder::append(java.lang.String) : java.lang.StringBuilder"
[VERBOSE]      Line 27, invoking "com.alibaba.demo.basic.DemoMock::innerFunc(java.lang.String) : java.lang.String"
[DIAGNOSE]     Line 27, mock method "innerFunc" used
... ...

输出日志结构参考如下：

• Mock constructor "<Mock方法名>" as "<方法签名>" for "<类型>" 在测试类中扫描到的Mock构造方法及其签名
• Mock method "<Mock方法名>" as "<方法签名>" 在测试类中扫描到的普通Mock方法及其签名
• Line XX, constructing "<类型>" as "<方法签名>" 在被测类中扫描掉的构造方法调用及其签名
• Line XX, invoking "<方法名>" as "<方法签名>" 在被测类中扫描到的成员方法调用及其签名

在0.4.x版本使用测试类添加@MockWith注解的diagnose参数来启用诊断信息的方法在0.5版本中依然可用，但将在未来版本中移除，请优先使用@MockDiagnose注解替代。