使用Androidx Test库中的ActivityScenario来模拟Activity生命周期，并添加LocaleChangeCallback监听语言环境的变化。示例如下：

import androidx.test.core.app.ActivityScenario
import androidx.test.runner.AndroidJUnit4
import org.junit.After
import org.junit.Before
import org.junit.Test
import org.junit.runner.RunWith
import java.util.*

@RunWith(AndroidJUnit4::class)
class MyTest{

    private lateinit var activityScenario: ActivityScenario
    private var testLocale: Locale = Locale("es", "ES") //设置测试语言环境

    @Before
    fun setUp() {
        Locale.setDefault(testLocale)
        activityScenario = ActivityScenario.launch(MyActivity::class.java)
        activityScenario.onActivity {
            val config = it.resources.configuration
            config.setLocale(testLocale)
            it.createConfigurationContext(config)
        }
    }

    @After
    fun tearDown() {
        activityScenario.close()
    }

    @Test
    fun testLocaleChange() {
        val config = activityScenario.launch().result.get().resources.configuration
        assert(config.locale == testLocale)
        Locale.setDefault(Locale("en","US")) //切换系统语言环境
        activityScenario.onActivity {
            val newConfig = it.resources.configuration
            if (newConfig.locale != testLocale){
                //语言环境改变
            }
            assert(newConfig.locale == Locale.getDefault())
        }
    }

    @Test
    fun testSomethingElse(){
        // other tests
    }

}