eMadrid seminar on «Serious games applied to teaching in software engineering», organized by UCM. Authors: Gordon Fraser and Phil Werli, from Passau University (Germany).

1. CODE DEFENDERSCODE DEFENDERS
GAMIFICATION OF MUTATION TESTINGGAMIFICATION OF MUTATION TESTING
Phil Werli - Student ResearcherPhil Werli - Student Researcher
Chair of Software Engineering II, University of PassauChair of Software Engineering II, University of Passau
Prof. Gordon FraserProf. Gordon Fraser
22. November 2019 - Madrid22. November 2019 - Madrid
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2. TEACHING SOFTWARE TESTINGTEACHING SOFTWARE TESTING
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3. CHALLENGECHALLENGE
Find an interesting way to teach Software Testing
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4. MUTATION TESTINGMUTATION TESTING
1970’s — DeMillo (Georgia Tech), Lipton (Princeton), Sayward (Yale)
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5. MUTATION TESTINGMUTATION TESTING
1970’s — DeMillo (Georgia Tech), Lipton (Princeton), Sayward (Yale)
Measure quality of existing tests
Modify source code: Mutants
Tests may detect and kill Mutants
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6. EXAMPLEEXAMPLE
Original Code
int abs(int x) {
if (x >= 0) {
return x
} else {
return -x;
}
}
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7
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7. EXAMPLEEXAMPLE
Original Code
Test
int abs(int x) {
if (x >= 0) {
return x
} else {
return -x;
}
}
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@Test
void testAbs() {
int res = abs(42);
assertEquals(42, res); // true
}
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8. MUTATIONMUTATION
Mutant
if (x <= 0) {
int abs(int x) {1
2
return x3
} else {4
return -x;5
}6
}7
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9. MUTATIONMUTATION
Mutant
Killing Test
if (x <= 0) {
int abs(int x) {1
2
return x3
} else {4
return -x;5
}6
}7
@Test
void testAbs() {
int res = abs(42);
assertEquals(42, res); // false -> mutant discovered
}
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10. New Mutant
return -x + 1;
int abs(int x) {1
if (x >= 0) {2
return x3
} else {4
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}6
}7
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11. New Mutant
New Test
return -x + 1;
int abs(int x) {1
if (x >= 0) {2
return x3
} else {4
5
}6
}7
@Test
void testAbs() {
// ???
}
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12. EQUIVALENCESEQUIVALENCES
Original Code
Equivalent Mutant
int abs(int x) {
if (x >= 0) {
return x
} else {
return -x;
}
}
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int abs(int x) {
if (x >= 0) {
return x
} else {
return -x + 0;
}
}
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13. CODE DEFENDERSCODE DEFENDERS
Attackers vs. Defenders
Attackers spawn Mutants
Defenders defend with Tests
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14. LIVE DEMOLIVE DEMO
Enough talking...Enough talking...
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15. SOFTWARE TESTING COURSE @ UNI PASSAUSOFTWARE TESTING COURSE @ UNI PASSAU
2h Lecture
1h Exercise
2h Lab Session
around 120 students
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16. Lab SessionsLab Sessions
1 session per week per student
Teams of 3-5 students
Students play both roles
Increasing difficulty
Count towards grade
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17. Four Challenges
Classroom Management Games Management
Course Management Assessment
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18. LIVE DEMOLIVE DEMO
Admin interfaceAdmin interface
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19. COURSE DATA & STUDYCOURSE DATA & STUDY
Data per game
Data per student
Study with data from our course
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20. IMPROVEMENT THROUGHOUT SEMESTERIMPROVEMENT THROUGHOUT SEMESTER
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21. GAME ACTIVITY VS. EXAM GRADESGAME ACTIVITY VS. EXAM GRADES
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22. ANONYMOUS SURVEYANONYMOUS SURVEY
84% learned useful skills as defenders
60% learned useful skills as attackers
=> Make people defend more=> Make people defend more
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23. FUTURE CHALLENGESFUTURE CHALLENGES
Communication mechanism to foster collaboration
Many opportunities to spice up gameplay
Integrate more technologies & features
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24. PUBLICLY AVAILABLEPUBLICLY AVAILABLE
code-defenders.org
github.com/CodeDefenders
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25. Overview
Play onlinePlay online
Source CodeSource Code
https://code-defenders.orghttps://code-defenders.org
github.com/CodeDefendersgithub.com/CodeDefenders
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26. CHAIR & SPEAKER CONTACTCHAIR & SPEAKER CONTACT
Presentation created usingPresentation created using
Chair of Software Engineering II
github.com/werli
reveal.jsreveal.js
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