UseAssertNullInsteadOfAssertTrue

This rule detects JUnit assertions in object references equality. These assertions should be made by more specific methods, like assertNull, assertNotNull.

This rule is defined by the following XPath expression:

                 
//PrimaryExpression[
 PrimaryPrefix/Name[@Image = 'assertTrue' or @Image = 'assertFalse']
][
 PrimarySuffix/Arguments/ArgumentList[
  Expression/EqualityExpression/PrimaryExpression/PrimaryPrefix/Literal/NullLiteral
 ]
]
[ancestor::ClassOrInterfaceDeclaration[//ClassOrInterfaceType[typeof(@Image, 'junit.framework.TestCase','TestCase')] or //MarkerAnnotation/Name[typeof(@Image, 'org.junit.Test', 'Test')]]]
  
             

Example:

                
 
 public class FooTest extends TestCase {
  void testCode() {
   Object a = doSomething();
   assertTrue(a==null); // bad usage
   assertNull(a);  // good usage
   assertTrue(a != null); // bad usage
   assertNotNull(a);  // good usage
  }
 }