MUTATION TESTING
NO MORE FAIRY TALES
SPEAKER
{
"name": "ng-henry-ruhs",
"description": "Senior Frontend Engineer at Avantgarde Labs",
"version": "1.9.82",
"license": "GPL-3.0",
"keywords":
[
"CMS Founder",
"Frontend Architect",
"JavaScript Evangelist",
"WPO Expert",
"GitHub Fanboy"
],
"website": "https://redaxmedia.com",
"twitter": "https://twitter.com/redaxmedia",
"github": "https://github.com/redaxmedia"
}MUTATION TESTING
OVERVIEW
WHY IT MATTERS
HYPOTHESIS
BASIC CONCEPTS
IN PRACTICE
CONLUSIONS WE DRAW
MUTATION TESTING
WHY IT MATTERS
1. Measure Quality
2. Uncover Gaps
3. Detect Faults
4. Uncover Ambiguities
5. Improve Stability
MUTATION TESTING
HYPOTHESIS
1. Competent Programmer
2. Coupling Effect
MUTATION TESTING
BASIC CONCEPTS
1. Mutators
2. Mutants
3. Mutation Score
MUTATION TESTING
IN PRACTICE
"Let's kill a hord of mutants"
npm install stryker-cliINSTALL
module.exports = config =>
{
config.set(
{
mutator: 'typescript',
packageManager: 'npm',
reporters:
[
'clear-text'
],
testRunner: 'mocha',
testFramework: 'mocha',
tsconfigFile: 'tsconfig.json',
mochaOptions:
{
opts: 'tests/mocha.opts'
},
mutate:
[
'src/**/*.ts'
]
});
};
stryker initCONFIGURE
stryker runRUN
Ran 0.64 tests per mutant on average.
--------------------|---------|----------|-----------|------------|----------|---------|
File | % score | # killed | # timeout | # survived | # no cov | # error |
--------------------|---------|----------|-----------|------------|----------|---------|
All files | 100.00 | 54 | 0 | 0 | 0 | 36 |
common.service.ts | 100.00 | 33 | 0 | 0 | 0 | 21 |
crud.module.ts | 100.00 | 2 | 0 | 0 | 0 | 0 |
crud.service.ts | 100.00 | 12 | 0 | 0 | 0 | 8 |
delete.service.ts | 100.00 | 1 | 0 | 0 | 0 | 1 |
get.service.ts | 100.00 | 2 | 0 | 0 | 0 | 2 |
patch.service.ts | 100.00 | 1 | 0 | 0 | 0 | 1 |
post.service.ts | 100.00 | 1 | 0 | 0 | 0 | 1 |
put.service.ts | 100.00 | 1 | 0 | 0 | 0 | 1 |
request.service.ts | 100.00 | 1 | 0 | 0 | 0 | 1 |
--------------------|---------|----------|-----------|------------|----------|---------|
"Time for a live demo"
MUTATION TESTING
CONCLUSIONS WE DRAW
1. Evaluates testing quality
2. Extremely time consuming
3. Highest level of stability
4. Slow execution time
"Ask your question now"
process.exit();