I also see assertEquals() between objects of inconvertible types 'List ' and 'List ' at line 251 assertEquals() between objects of inconvertible types 'Object' and 'double' at line 149 assertEquals() between objects of inconvertible types 'Object' and 'int' at line 309 assertEquals() between objects of inconvertible types 'Object' and 'long' at line 88 assertEquals() between objects of inconvertible types 'Object' and 'byte' at line 46 assertEquals() between objects of inconvertible types 'Object' and 'char' at line 53 assertEquals() between objects of inconvertible types 'Object' and 'short' at line 26 assertEquals() between objects of inconvertible types 'Map ' and 'Map ' at line 33 assertEquals() between objects of inconvertible types 'CheckedSet ? extends DataValue,?>>' and 'CheckedSet >' at line 483 I am assuming there are three issues here. 1) If the generics are inconvertible it complains is the generic types are different. The tool tip appear have a more meaningful message but the inspections code message is confusing. e.g. The first array is List<String> but it thinks the second is List<Object> assertEquals(Arrays.asList(STRING_DATA), Arrays.asList(list1.toArray())); 2) The check doesn't take in account auto boxing. 3) The code inspection message sometimes has 'Set??' or 'List??' or 'Map??' which doesn't appear in the cut-and-paste. In the last example the type is really confused. Perhaps the render doesn't like < ?