使用 Mockito，我如何匹配地图的键值对? [英] Using Mockito, how do I match against the key-value pair of a map?

问题描述

我需要根据特定键值从模拟对象发送特定值.

I need to send a specific value from a mock object based on a specific key value.

从具体类:

map.put("xpath", "PRICE");
search(map);

来自测试用例:

IOurXMLDocument mock = mock(IOurXMLDocument.class);
when(mock.search(.....need help here).thenReturn("$100.00");

我如何模拟这个键值对的方法调用?

How do I mock this method call for this key value pair?

推荐答案

我发现这试图解决创建带有 Map 参数的 Mockito 存根的类似问题.我不想为有问题的地图编写自定义匹配器，然后我找到了一个更优雅的解决方案:使用 hamcrest-library 与 mockito 的 argThat:

I found this trying to solve a similar issue creating a Mockito stub with a Map parameter. I didn't want to write a custom matcher for the Map in question and then I found a more elegant solution: use the additional matchers in hamcrest-library with mockito's argThat:

when(mock.search(argThat(hasEntry("xpath", "PRICE"))).thenReturn("$100.00");

如果您需要检查多个条目，那么您可以使用其他 hamcrest 好东西:

If you need to check against multiple entries then you can use other hamcrest goodies:

when(mock.search(argThat(allOf(hasEntry("xpath", "PRICE"), hasEntry("otherKey", "otherValue")))).thenReturn("$100.00");

对于非平凡的地图，这开始变得很长，所以我最终提取了方法来收集条目匹配器并将它们卡在我们的 TestUtils 中:

This starts to get long with non-trivial maps, so I ended up extracting methods to collect the entry matchers and stuck them in our TestUtils:

import static org.hamcrest.Matchers.allOf;
import static org.hamcrest.Matchers.anyOf;
import static org.hamcrest.Matchers.hasEntry;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

import org.hamcrest.Matcher;
---------------------------------
public static <K, V> Matcher<Map<K, V>> matchesEntriesIn(Map<K, V> map) {
    return allOf(buildMatcherArray(map));
}

public static <K, V> Matcher<Map<K, V>> matchesAnyEntryIn(Map<K, V> map) {
    return anyOf(buildMatcherArray(map));
}

@SuppressWarnings("unchecked")
private static <K, V> Matcher<Map<? extends K, ? extends V>>[] buildMatcherArray(Map<K, V> map) {
    List<Matcher<Map<? extends K, ? extends V>>> entries = new ArrayList<Matcher<Map<? extends K, ? extends V>>>();
    for (K key : map.keySet()) {
        entries.add(hasEntry(key, map.get(key)));
    }
    return entries.toArray(new Matcher[entries.size()]);
}

所以我只剩下:

when(mock.search(argThat(matchesEntriesIn(map))).thenReturn("$100.00");
when(mock.search(argThat(matchesAnyEntryIn(map))).thenReturn("$100.00");

泛型有一些丑陋之处，我正在取消一个警告，但至少它是 DRY 并且隐藏在 TestUtil 中.

There's some ugliness associated with the generics and I'm suppressing one warning, but at least it's DRY and hidden away in the TestUtil.

最后一点，请注意 嵌入式 hamcrestJUnit 4.10 中的问题.使用 Maven，我建议先导入 hamcrest-library，然后再导入 JUnit 4.11(现在是 4.12)，并从 JUnit 中排除 hamcrest-core，只是为了更好地衡量:

One last note, beware the embedded hamcrest issues in JUnit 4.10. With Maven, I recommend importing hamcrest-library first and then JUnit 4.11 (now 4.12) and exclude hamcrest-core from JUnit just for good measure:

<dependency>
    <groupId>org.hamcrest</groupId>
    <artifactId>hamcrest-library</artifactId>
    <version>1.3</version>
    <scope>test</scope>
</dependency>
<dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>4.12</version>
    <scope>test</scope>
    <exclusions>
        <exclusion>
            <groupId>org.hamcrest</groupId>
            <artifactId>hamcrest-core</artifactId>
        </exclusion>
    </exclusions>
</dependency>
<dependency>
    <groupId>org.mockito</groupId>
    <artifactId>mockito-all</artifactId>
    <version>1.9.5</version>
    <scope>test</scope>
</dependency>

<小时>

2017 年 9 月 1 日 - 根据一些评论，我更新了答案以显示我的 Mockito 依赖项、我在测试实用程序中的导入以及截至今天运行绿色的 junit:

---

Sept 1, 2017 - Per some of the comments, I updated my answer to show my Mockito dependency, my imports in the test util, and a junit that is running green as of today:

import static blah.tool.testutil.TestUtil.matchesAnyEntryIn;
import static blah.tool.testutil.TestUtil.matchesEntriesIn;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.is;
import static org.mockito.Matchers.argThat;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;

import java.util.HashMap;
import java.util.Map;

import org.junit.Test;

public class TestUtilTest {

    @Test
    public void test() {
        Map<Integer, String> expected = new HashMap<Integer, String>();
        expected.put(1, "One");
        expected.put(3, "Three");

        Map<Integer, String> actual = new HashMap<Integer, String>();
        actual.put(1, "One");
        actual.put(2, "Two");

        assertThat(actual, matchesAnyEntryIn(expected));

        expected.remove(3);
        expected.put(2, "Two");
        assertThat(actual, matchesEntriesIn(expected));
    }

    @Test
    public void mockitoTest() {
        SystemUnderTest sut = mock(SystemUnderTest.class);
        Map<Integer, String> expected = new HashMap<Integer, String>();
        expected.put(1, "One");
        expected.put(3, "Three");

        Map<Integer, String> actual = new HashMap<Integer, String>();
        actual.put(1, "One");

        when(sut.search(argThat(matchesAnyEntryIn(expected)))).thenReturn("Response");
        assertThat(sut.search(actual), is("Response"));
    }

    protected class SystemUnderTest {
        // We don't really care what this does
        public String search(Map<Integer, String> map) {
            if (map == null) return null;
            return map.get(0);
        }
    }
}

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