Details
Description
It is very easy to write incomplete assertions when using some test frameworks. This rule enforces complete assertions in the following cases:
- Fest: assertThat is not followed by an assertion invocation
- AssertJ: assertThat is not followed by an assertion invocation
- Mockito: verify is not followed by a method invocation
- Truth: assertXXX is not followed by an assertion invocation
In such cases, what is intended to be a test doesn't actually verify anything
Noncompliant Code Example
// Fest boolean result = performAction(); // let's now check that result value is true assertThat(result); // Noncompliant; nothing is actually checked, the test passes whether "result" is true or false // Mockito List mockedList = Mockito.mock(List.class); mockedList.add("one"); mockedList.clear(); // let's check that "add" and "clear" methods are actually called Mockito.verify(mockedList); // Noncompliant; nothing is checked here, oups no call is chained to verify()
Compliant Solution
// Fest boolean result = performAction(); // let's now check that result value is true assertThat(result).isTrue(); // Mockito List mockedList = Mockito.mock(List.class); mockedList.add("one"); mockedList.clear(); // let's check that "add" and "clear" methods are actually called Mockito.verify(mockedList).add("one"); Mockito.verify(mockedList).clear();
Exceptions
Variable assignments and return statements are skipped to allow helper methods.
private BooleanAssert check(String filename, String key) { String fileContent = readFileContent(filename); performReplacements(fileContent); return assertThat(fileContent.contains(key)); // No issue is raised here } @Test public void test() { check("foo.txt", "key1").isTrue(); check("bar.txt", "key2").isTrue(); }
