使用 JUnit 参数化测试和 Mockito 模拟对象返回值

import org.junit.jupiter.api.extension.ExtendWith;
import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.Arguments;
import org.junit.jupiter.params.provider.MethodSource;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.junit.jupiter.MockitoExtension;

import java.util.stream.Stream;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.mockito.Mockito.when;

@ExtendWith(MockitoExtension.class)
public class FooTest {

    @Mock
    MockedObject mockedObject;

    @InjectMocks
    Foo underTest;

    @ParameterizedTest
    @MethodSource("dataProvider")
    public void test_ParametrizedTest(MockedInput mockedInput, Output expectedReturn) {

        // Given
        when(mockedObject.method(mockedInput))
            .thenReturn(expectedReturn);

        // when
        Output result = underTest.method();

        // then
        assertEquals(expectedReturn.getCode(), result.getCode());

    }

    private static Stream<Arguments> dataProvider() {
        return Stream.of(
            Arguments.of(new MockedInput("S1"), new Output("S1")),
            Arguments.of(new MockedInput("S2"), new Output("S2"))
        );
    }

    // 辅助类，用于模拟输入和输出
    static class MockedInput {
        private String code;

        public MockedInput(String code) {
            this.code = code;
        }

        public String getCode() {
            return code;
        }
    }

    static class Output {
        private String code;

        public Output(String code) {
            this.code = code;
        }

        public String getCode() {
            return code;
        }
    }

    // 被测试类
    static class Foo {
        private MockedObject mockedObject;

        public Foo(MockedObject mockedObject) {
            this.mockedObject = mockedObject;
        }

        public Output method() {
            MockedInput input = new MockedInput("S1"); // 假设这里创建了input
            return mockedObject.method(input);
        }
    }

    // 被模拟的类
    static class MockedObject {
        public Output method(MockedInput input) {
            return new Output(input.getCode()); // 实际实现会被mock掉
        }
    }
}