android中的Callbacks如何编写测试用例？

Question

我想为只调用另一个任务但不返回任何内容的覆盖方法编写一个测试用例。

Answer 1

这是一个简单的例子：

build.gradle：

    testImplementation 'junit:junit:4.12'
    testImplementation 'org.powermock:powermock-module-junit4:1.6.6'
    testImplementation 'org.powermock:powermock-module-junit4-rule:1.6.6'
    testImplementation 'org.powermock:powermock-api-mockito:1.6.6'
    testImplementation 'org.powermock:powermock-classloading-xstream:1.6.6'
    testImplementation 'org.robolectric:robolectric:3.3.2'
    testImplementation "org.robolectric:robolectric-annotations:3.3.2"
    testImplementation "org.robolectric:shadows-support-v4:3.3.2"

AppUtils.java。 这里我们有两种方法来测试。

package com.example.myapplication.utils;

import android.content.Context;
import android.util.Log;

public class AppUtils {
    public interface TResultRunnable <T>{
        public void onSuccess(T result);
        public void onFail(Exception e);
    }
    public static void parseIntWithCallback(String value, TResultRunnable<Integer> tResultRunnable ){
        int intVal = 0;
        try {
            intVal = Integer.parseInt(value);
            tResultRunnable.onSuccess(intVal);
        } catch (Exception e) {
            tResultRunnable.onFail(e);
        }
    }
    public static void parseIntWithCallback2(Context context, String value, TResultRunnable<Integer> tResultRunnable ){
        Log.i("test", "method begin. package="+context.getPackageName());

        int intVal = 0;
        try {
            intVal = Integer.parseInt(value);
            tResultRunnable.onSuccess(intVal);
            Log.i("test", "method success");

        } catch (Exception e) {
            Log.e("test", "method exception "+e);
            tResultRunnable.onFail(e);
        }
    }


}

ExampleUnitTest.java 在 src/test/java/com/example/myapplication 文件夹中。

package com.example.myapplication;

import android.content.Context;
import android.util.Log;

import com.example.myapplication.utils.AppUtils;

import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.powermock.api.mockito.PowerMockito;
import org.powermock.core.classloader.annotations.PrepareForTest;
import org.powermock.modules.junit4.PowerMockRunner;

import static org.mockito.Mockito.*;

@RunWith(PowerMockRunner.class)
@PrepareForTest({AppUtils.class, Log.class})
public class ExampleUnitTest {
    @Before
    public void setUp() {
        PowerMockito.mockStatic(Log.class);
    }
    @Test
    public void test_parseInt() {
        {
            AppUtils.TResultRunnable<Integer> mockListener = mock(AppUtils.TResultRunnable.class);
            AppUtils.parseIntWithCallback("1000", mockListener);
            verify(mockListener, never()).onFail(any(Exception.class));
            verify(mockListener, times(1)).onSuccess(1000);
        }
        {
            AppUtils.TResultRunnable<Integer> mockListener = mock(AppUtils.TResultRunnable.class);
            AppUtils.parseIntWithCallback("xxx", mockListener);
            verify(mockListener, times(1)).onFail(any(Exception.class));
            verify(mockListener, never()).onSuccess(anyInt());
        }
    }
    @Test
    public void test_parseIntWithCallback2() {
        Context context = mock(Context.class);

        {
            AppUtils.TResultRunnable<Integer> mockListener = mock(AppUtils.TResultRunnable.class);
            AppUtils.parseIntWithCallback2(context, "1000", mockListener);
            verify(mockListener, never()).onFail(any(Exception.class));
            verify(mockListener, times(1)).onSuccess(1000);
        }
        {
            AppUtils.TResultRunnable<Integer> mockListener = mock(AppUtils.TResultRunnable.class);
            AppUtils.parseIntWithCallback2(context, "xxx", mockListener);
            verify(mockListener, times(1)).onFail(any(Exception.class));
            verify(mockListener, never()).onSuccess(anyInt());
        }
    }

}