How can I refactor my code to minimize the need for Mockito's reset method

1. Write Simple and Focused Test Methods**

Instead of using `reset` to reuse mocks across multiple scenarios within a single test, break down your tests into smaller, more focused methods. Each test should verify a specific behavior or condition, making it easier to manage and maintain your test suite.

java
// Before: Using reset
@Test
public void testMultipleScenarios() {
    // Setup mock
    Mockito.when(mockObject.doSomething()).thenReturn("Result1");
    
    // Test scenario 1
    // ...
    
    Mockito.reset(mockObject);
    
    Mockito.when(mockObject.doSomething()).thenReturn("Result2");
    
    // Test scenario 2
    // ...
}

// After: Separate tests
@Test
public void testScenario1() {
    Mockito.when(mockObject.doSomething()).thenReturn("Result1");
    // Test scenario 1
}

@Test
public void testScenario2() {
    Mockito.when(mockObject.doSomething()).thenReturn("Result2");
    // Test scenario 2
}

2. Avoid Complex Logic in Constructors**

Constructors should ideally only initialize objects and not execute complex logic. If your constructors call methods that need to be mocked, consider refactoring to use factory methods or pass the results of those methods as constructor arguments.

java
// Before: Constructor with logic
public class MyClass {
    public MyClass() {
        init();
    }
    
    private void init() {
        // Logic that needs mocking
    }
}

// After: Using a factory method
public class MyClass {
    private MyClass() {}
    
    public static MyClass create() {
        MyClass instance = new MyClass();
        instance.init();
        return instance;
    }
    
    private void init() {
        // Logic that needs mocking
    }
}

3. Extract Methods and Reduce Cognitive Complexity**

High cognitive complexity can lead to tests that are hard to manage. By extracting methods and simplifying logic, you reduce the need for complex mocking scenarios.

java
// Before: Complex method
public void doSomething() {
    if (condition1) {
        // Logic 1
    } else if (condition2) {
        // Logic 2
    }
}

// After: Extracted methods
public void doSomething() {
    if (condition1) {
        logic1();
    } else if (condition2) {
        logic2();
    }
}

private void logic1() {
    // Logic 1
}

private void logic2() {
    // Logic 2
}

4. Use `clearInvocations` Instead of `reset`**

If you need to clear invocations but keep stubbing intact, use `Mockito.clearInvocations(mock)` instead of `reset`. This method clears the invocation history without resetting stubs.

java
Mockito.clearInvocations(mockObject);

5. Refactor to Reduce Duplication in Tests**

If your tests have duplicated setup or logic, consider extracting helper methods or classes that encapsulate this logic. This can reduce the need for complex mocking and resetting.

java
// Before: Duplicate setup
@Test
public void testScenario1() {
    setupMock();
    // Test scenario 1
}

@Test
public void testScenario2() {
    setupMock();
    // Test scenario 2
}

// After: Extracted setup method
private void setupMock() {
    // Common setup logic
}

@Test
public void testScenario1() {
    setupMock();
    // Test scenario 1
}

@Test
public void testScenario2() {
    setupMock();
    // Test scenario 2
}

By applying these strategies, you can significantly reduce the need for Mockito's `reset` method, leading to cleaner, more maintainable tests.