I'd argue that the absence of assertNotEqual is indeed an asymmetry and makes JUnit a bit less learnable. Mind that this is a neat case when adding a method would diminish the complexity of the API, at least for me: Symmetry helps ruling the bigger space. My guess is that the reason for the omission may be that there are too few people calling for the method. Yet, I remember a time when even assertFalse did not exist; hence, I have a positive expectation that the method might eventually be added, given that it is not a difficult one; even though I acknowledge that there are numerous workarounds, even elegant ones.

I'd argue that the absence of assertNotEqual is indeed an asymmetry and makes JUnit a bit less learnable. Mind that this is a neat case when adding a method would diminish the complexity of the API, at least for me: Symmetry helps ruling the bigger space. My guess is that the reason for the omission may be that there are too few people calling for the method. Yet, I remember a time when even assertFalse did not exist; hence, I have a positive expectation that the method might eventually be added, given that it is not a difficult one; even though I acknowledge that there are numerous workarounds, even elegant ones.

对于否定的断言，最好使用Hamcrest，而不是assertFalse，因为在前者中，测试报告将显示断言失败的差异。

如果使用assertFalse，只会在报告中得到一个断言失败。例如，丢失了关于失败原因的信息。

通常当我期望两个对象相等时，我这样做:

assertTrue(obj1.equals(obj2));

and:

assertFalse(obj1.equals(obj2));

当他们被认为是不平等的。我知道这不是对你问题的回答，但这是我能得到的最接近的答案。它可以帮助其他人搜索在JUnit 4.11之前的JUnit版本中可以做什么。

Modulo API一致性，JUnit不提供assertNotEquals()的原因与JUnit从未提供类似方法的原因相同

assertStringMatchesTheRegex（regex， str） vs. assertStringDoesntMatchTheRegex（regex， str） assertStringBeginsWith（prefix， str） vs. assertStringDoesntBeginWith（prefix， str）

也就是说，为断言逻辑中可能需要的东西提供特定的断言方法是无止境的!

更好的方法是提供可组合的测试原语，如equalTo(…)、is(…)、not(…)、regex(…)，并让程序员将这些原语拼凑在一起，以获得更好的可读性和合理性。

JUnit 4.11中有一个assertNotEquals: https://github.com/junit-team/junit/blob/master/doc/ReleaseNotes4.11.md#improvements-to-assert-and-assume

import static org.junit.Assert.assertNotEquals;