测试失败，而它不应该失败？

Question

我有这个测试柜：

void loadFromJson() throws Exception
{
    assertThrows(FileNotFoundException.class, ()-> JsonReader.loadFromJson(".json"));
}

这应该抛出一个fileNotfoundException ...并且它确实...

java.io.FileNotFoundException: .json (No such file or directory)
at java.io.FileInputStream.open0(Native Method)
at java.io.FileInputStream.open(FileInputStream.java:195)
at java.io.FileInputStream.<init>(FileInputStream.java:138)
at java.io.FileInputStream.<init>(FileInputStream.java:93)
at java.io.FileReader.<init>(FileReader.java:58)
at org.avalin.optaplanner.json.JsonReader.loadFromJson(JsonReader.java:29)

但是我遇到了这个错误：

org.opentest4j.AssertionFailedError: Expected java.io.FileNotFoundException to be thrown, but nothing was thrown.
at org.junit.jupiter.api.AssertThrows.assertThrows(AssertThrows.java:65)
at org.junit.jupiter.api.AssertThrows.assertThrows(AssertThrows.java:38)
at org.junit.jupiter.api.Assertions.assertThrows(Assertions.java:1108)
at org.avalin.optaplanner.test.unitTest.JsonReaderTest.loadFromJson(JsonReaderTest.java:16)

我的测试柜失败了...当它实际抛出请求的异常时，这是怎么可能的？

Answer 1

我对jupiter.api.AssertThrows不熟悉，但是很容易设置一个忽略/绕过的测试，并简单地测试代码的lambda方面。

这里的要点是创建lambda不运行代码，直到您，er，运行代码。

。

因此，以下是3个单位测试。test1和test3都投掷AssertionError，但test2却没有。AssertThrows()中的工作方式，我会让您或其他人回答。

public class TestTest {
   @Test(expected = AssertionError.class)
   public void test1() {
       throw new AssertionError();
   }
   @Test(expected = AssertionError.class)
   public void test2() {
     Runnable r = () -> {throw new AssertionError();};
   }
   @Test(expected = AssertionError.class)
   public void test3() {
     Runnable r = () -> {throw new AssertionError();};
     r.run();
   }
}