# Change Based Fault Localization

This is a library that can be used to automatically find points of failure in TypeScript Modules that are tested with Mocha.

Integrate it into you workflow by creating a `hooks.js` file.
The file should look like this:

```javascript
const createFailureLocalizationHooks = require("cbfl").default;
const options = {
  mochaCommand:
    "TS_NODE_FILES=true node ./node_modules/mocha/bin/mocha -r ts-node/register -r require-yaml -r ./test/hooks.js -t 200000", // here you can add your own requires and set a timeout according to your needs
  targetBranch: process.env.CI_MERGE_REQUEST_TARGET_BRANCH_NAME, // if you have this variable available otherwise use the name of your main branch (main / master)
  gitlabApiToken: process.env.OAuthToken, // this is the gitlab authentication token that should be used to create comments on the merge request
};
const hooks = createFailureLocalizationHooks(options);
exports.mochaHooks = {
  async beforeAll() {
    hooks.beforeAll();
  },
  async afterAll() {
    hooks.afterAll();
  },
  async afterEach() {
    hooks.afterEach(this.currentTest);
  },
};
```

Now whenever/wherever you execute mocha remember to add ` -r hooks.js` to the mocha command. The fault localization happens automatically using mocha root hooks.