Fault localization using condition modeling and return value modeling

• US 9,043,761 B2
• Filed: 09/01/2010
• Issued: 05/26/2015
• Est. Priority Date: 09/01/2010
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Artzi, Shay, Dolby, Julian, Pistoia, Marco, Tip, Frank
• Primary Examiner(s): Dao, Thuy
• Assistant Examiner(s): HAYIM, SAMUEL E
• Application Number:
  US12/873,843
• Publication Number:
  US 20120054553A1
• Time in Patent Office: 1,728 Days
• Field of Search: None
• US Class Current: 717/131
• CPC Class Codes: G06F 11/3688 for test execution, e.g. scheduling of test suites
• CPC Class Codes: G06F 11/3692 for test results analysis

Abstract

Disclosed is a novel computer implemented system, on demand service, computer program product and a method that leverages combined concrete and symbolic execution and several fault-localization techniques to automatically detects failures and localizes faults in PHP Hypertext Preprocessor (“PHP”) Web applications.

Claims

1. A computer-implemented method to localize faults in a software application, the computer-implemented method comprising:

receiving a set of tests to apply on a software application, wherein the software includes both unknown fault paths and known fault paths;

associating one or more domain elements with the software;

receiving a statistical fault localization technique that uses the set of tests to localize at least one fault in the domain elements based on those domain elements appearing in passing and failing tests;

executing each test in the set of tests on the software application, and recording, for each executed test, a set of test information including;

a test outcome on whether a specific fault has occurred, wherein a passing test is the test outcome with no fault that has occurred, and a failing test is the test outcome with a fault that has occurred;

one or more executed statements in the software application, and

for each execution of each executed statement in the software application, compute an abstract value based on its runtime behavior that indicates a domain element to which that statement execution corresponds;

using the statistical fault localization technique which has been received, calculating a suspiciousness rating for each of the domain elements based on the set of test information which has been recorded, wherein the suspiciousness rating is computed for each executed domain element as a percentage of passing and failing tests that execute that domain element; and

reporting a list containing a suspiciousness rating for each domain element in one of a decreasing order of suspiciousness rating and an increasing order of suspiciousness rating.

2. The computer implemented method of claim 1, wherein the domain element is at least one of:

a pair comprising of a conditional statement and a value that identifies a branch of that conditional statement; and

an unconditional statement.

3. The computer implemented method of claim 1, wherein the domain element is at least one of:

a pair comprising of a call to a function, and an abstract representation of a return value of that function; and

a statement other than a function call.

4. The computer implemented method of claim 1, wherein the executed statements in the software application includes one or more function calls and wherein the executing each test in the set of tests, and recording the set of test information further includes recording:

an abstract model of a result for each execution of the function calls.

5. The computer implemented method of claim 1, wherein the executed statements in the software application includes one or more of branches, statements, and functions.

6. The computer implemented method of claim 1, wherein the executing each test in set of tests, and recording the set of test information further includes recording one of:

a pass outcome;

a fail outcome; and

an exception outcome.

7. The computer implemented method of claim 2, wherein the conditional statement is one of:

a while statement;

an if statement; and

a switch statement.

8. A computer program product for analyzing an application comprising a plurality of code fragments, the computer program product comprising:

a non-transitory storage medium readable by a computer system, the non-transitory storage medium storing software programming instructions capable of performing with a processor programming code to carry out;

receiving a set of tests to apply on a software application, wherein the software includes both unknown fault paths and known fault paths;

associating one or more domain elements with the software;

receiving a statistical fault localization technique that uses the set of tests to localize at least one fault in the domain elements based on those domain elements appearing in passing and failing tests;

executing each test in the set of tests on the software application, and recording, for each executed test, a set of test information including;

a test outcome on whether a specific fault has occurred,

one or more executed statements in the software application, and

for each execution of each executed statement in the software application, compute an abstract value based on its runtime behavior that indicates a domain element to which that statement execution corresponds;

using the statistical fault localization technique which has been received, calculating a suspiciousness rating for each of the domain elements based on the set of test information which has been recorded, wherein the suspiciousness rating is computed for each executed domain element as a percentage of passing and failing tests that execute that domain element; and

reporting a list containing a suspiciousness rating for each domain element in one of a decreasing order of suspiciousness rating and an increasing order of suspiciousness rating.

9. The computer program product of claim 8, wherein the domain element is at least one of:

a pair comprising of a conditional statement and a value that identifies a branch of that conditional statement; and

an unconditional statement.

10. The computer program product of claim 8, wherein the domain element is at least one of:

a pair comprising of a call to a function, and an abstract representation of a return value of that function; and

a statement other than a function call.

11. The computer program product of claim 8, wherein the executed statements in the software application includes one or more function calls and wherein the executing each test in the set of tests, and recording the set of test information further includes recording:

an abstract model of a result for each execution of the function calls.

12. The computer program product of claim 8, wherein the executed statements in the software application includes one or more of branches, statements, and functions.

13. The computer program product of claim 8, wherein the executing each test in set of tests, and recording the set of test information further includes recording one of:

a pass outcome;

a fail outcome; and

an exception outcome.

14. The computer program product of claim 9, wherein the conditional statement is one of:

a while statement;

an if statement; and

a switch statement.

15. A system for analyzing an application comprising a plurality of code fragments, the system comprising:

a computer memory capable of storing machine instructions; and

a processor in communication with said computer memory, said processor capable of accessing said machine instructions to perform;

receiving a set of tests to apply on a software application, wherein the software includes both unknown fault paths and known fault paths;

associating one or more domain elements with the software;

receiving a statistical fault localization technique that uses the set of tests to localize at least one fault in the domain elements based on those domain elements appearing in passing and failing tests;

executing each test in the set of tests on the software application, and recording, for each executed test, a set of test information including;

a test outcome on whether a specific fault has occurred,

one or more executed statements in the software application, and

for each execution of each executed statement in the software application, compute an abstract value based on its runtime behavior that indicates a domain element to which that statement execution corresponds;

using the statistical fault localization technique which has been received, calculating a suspiciousness rating for each of the domain elements based on the set of test information which has been recorded, wherein the suspiciousness rating is computed for each executed domain element as a percentage of passing and failing tests that execute that domain element; and

reporting a list containing a suspiciousness rating for each domain element in one of a decreasing order of suspiciousness rating and an increasing order of suspiciousness rating.

16. The system of claim 15, wherein the domain element is at least one of:

a pair comprising of a conditional statement and a value that identifies a branch of that conditional statement; and

an unconditional statement.