Mutation Testing with Stryker

Last updated: Mar 25, 26 00:28 UTC | Permalink

Activity 3.2: Mutation Testing with Stryker

This activity is intended to supplement the CS4530 lecture on mutation testing development. You will need to have already completed the development environment setup for the class.

Steps

Get the starter code by cloning the transcript-service-m03 repository from GitHub
Run npm install inside the directory that is created when you unzip the download.
Check that every member of the group can run
```
npm run test
```
and see that the tests pass and give full branch and line coverage.
Check that every member of the group can run
```
npm run stryker
```
and see that 7 variants survive, associated with lines 40, 43, 53, 54, 70, 121, and 125.

Classify the surviving mutants into innocuous (didn’t introduce a bug) and non-innocuous (did introduce a bug).
In a new file src/additional.spec.ts, write tests that will kill each non-innocuous mutant. For each mutant that you classified as innocuous, write a comment explaining why you think it is innocuous. You can rerun npm run test to make sure your tests still pass, and rerun npm run stryker to see if your tests kill identify the bad mutants.
When you are done, submit src/additional.spec.ts as required by your instructor.

Grading Criteria: 10pts

+2 points for each mutant correctly classified as innocuous or non-innocuous, killed if non-innocuous, or explained if innocuous, up to a maximum of 10 points.