Tao Xie ( ) Advisor: David Notkin Department of Computer Science & Engineering, University of Washington, Seattle Syntactically identical to axioms in algebraic specifications Associated with counts of satisfying and violating instances 79 common tests and 29 special tests (8 tests are both common and special) identified out of 6777 automatically generated tests. 43 universal properties and 45 common properties.Solution Results for java.util.LinkedList Automatic Identification of Common and Special Object-Oriented Unit Tests Related Work Ernst et al., Dynamically Discovering Likely Program Invariants to Support Program Evolution, IEEE Trans. Softw. Eng, 01. Henkel & Diwan, Discovering Algebraic Specifications from Java Classes, ECOOP 03. Xie et al., Rostra: A Framework for Detecting Redundant Object-Oriented Unit Tests, ASE 04. Some Examples of Common/Special Tests Programmers often overlook some special or even common tests Automatic test generation tools produce a large number of tests How to automatically identify special tests and common tests from them?Problem Automatically identify common and special tests without requiring specifications Based on dynamically inferred Statistical Algebraic Abstractions Test generation Common or universal properties Java class bytecode Method-call composition Statistical inference Abstraction templates Test identification Special tests Common tests Common test a satisfying instance of a universal property or common property Special test a violating instance of a common property *. Common prop: remove(removeLast(S).state, m0_2).state == removeLast(remove(S, m0_2).state).state Satisfying count: 318 (common test) LinkedList m = new LinkedList( ); m.add (0, new Integer(-1)); m.removeLast( ); m.remove(new Integer(-1)); Violating count: 42 (special test) LinkedList m = new LinkedList( ); m.add (0, new Integer(-1)); m.add (0, new Integer(0)); m.removeLast( ); m.remove(new Integer(-1)); size(clear(S).state).retval == 0 Satisfying count: 121 Violating count: 0 remove(add(S, m0_1).state, m0_2).state == add(remove(S, m0_2).state, m0_1).state Satisfying count: 315 Violating count: 45 java.util.LinkedList as the illustrative example 25 pub methods and more than 300 LOC class bytecode Generate representative method arguments Iteratively invoke different arguments on each non- equivalent receiver-object (e.g. five iterations) [Xie et al. 04] clear S1S1 size S 2 == S 3 S4S4 … … g(f(S, args1).state, args2).retval == const g(f(S, args1).state, args2).state == f(g(S, args1).state, args2).state … Universal property: all instances are satisfying instances. Common property: instances are mostly (e.g. 80%) satisfying instances Statistical algebraic abstractions are not required to be universally true during test executions, different from properties inferred by previous approaches [Ernst et al. 01, Henkel & Diwan 03].References *. Common prop: remove(removeFirst(S).state, m0_2).retval == remove(S, m0_2).retval Satisfying count: 315 (common test) LinkedList m = new LinkedList( ); m.add (0, new Integer(-1)); m.removeFirst ( ); m.remove(new Integer(1)); Violating count: 45 (special test) LinkedList m = new LinkedList( ); m.add (0, new Integer(-1)); m.removeFirst ( ); m.remove(new Integer(-1)); *. Conditional universal prop: lastIndexOf(addFirst(S, m0_1).state, m0_2).retval == (lastIndexOf(S, m0_2).retval + 1) [where (m0_1==m0_2)] Satisfying count: 120 (special test) LinkedList m = new LinkedList( ); m.addFirst(new Integer(-1)); m.lastIndexOf(new Integer(-1)); *. Common prop: removeLast(addFirst(S, m0_1).state).state == addFirst(removeLast(S).state, m0_1).state Satisfying count: 117 (common test) LinkedList m = new LinkedList( ); m.add(0, new Integer(-1)); m.addFirst(new Integer(0)); m.removeLast ( ); Violating count: 3 (special test) LinkedList m = new LinkedList( ); m.addFirst(new Integer(0)); m.removeLast ( );