While using jest-addon with --json and --watch together an infinite loop is triggered

Describe the bug When using --json and --watch together a infinite jest test loop occurs

To Reproduce Steps to reproduce the behavior:

1. Create a simple jest test
2. Implement jest-addon
3. Create a script like this: "test:output:watch": "jest --json --outputFile=jest-lock.json --watch"
4. See infinite loop on console when running nom test:output:watch

Expected behavior There shouldn’t be a infinite loop, or how can I avoid it?

System:

• OS: MacOS
• Framework: react
• Addons: jest
• Version 4.0.0

What can I do to avoid it or how can I help in order to resolve this? Is this the right place to report it?

[rafistrauss]

As @igor-dv correctly reasoned, the output JSON file being (re)created on test completion is causing the watcher to rerun the tests. A simple workaround is to tell Jest to ignore the output, e.g by specifying the modulePathIgnorePatterns in your Jest config:

// my output json file is named jest-test-results.json, so:
modulePathIgnorePatterns: ['node_modules', 'jest-test-results.json'],

[fev4]

With the workaround the loop doesn’t happen. Thank you all