Introduction

PropWatch is a CI tool that catches breaking changes to test IDs before they fail your E2E suite.

The problem

When developers refactor components they often rename or remove testID, data-testid, or similar props without realising that E2E tests depend on them. The tests fail — sometimes minutes later in CI, sometimes days later in a staging environment.

PropWatch runs in your pull request pipeline, diffs the changed files against the base branch, and reports which IDs were removed or renamed. You find out immediately, in the same PR that introduced the change.

What it detects

Status	Example	Breaking?
Added	A new testID="submit-button" appeared	No — informational only
Changed	"submit-btn" renamed to "submit-button" on the same line	Yes
Removed	testID="submit-btn" deleted entirely	Yes

How it works

1. Runs git diff to find changed files in your branch
2. Extracts test IDs from both the base version and the current version of each file
3. Compares the two sets to identify additions, changes, and removals
4. Outputs results via your configured reporters

See How It Works for a deeper look at the diffing algorithm.

Supported ID types

Out of the box:

• testID / testId in JSX/TSX (React, React Native)
• data-testid in HTML, Vue, Svelte, Astro

Any prop or attribute is configurable via patterns.

Next steps

• Installation — install via npm, npx, Bun, or Docker
• Quick Start — up and running in 5 minutes
• CI/CD Setup — add PropWatch to your pipeline