@averspec/approvals

Status: Early release. API is stabilizing. Breaking changes will be noted in release notes.

Approval testing for Aver — structural diffs and visual regression.

Install

npm install @averspec/approvals

Requires @averspec/core as a peer dependency.

Usage

Structural Approvals

Use approve(value) to compare text or JSON output against a saved baseline. On first run, set AVER_APPROVE=1 to create the baseline file.

import { approve } from '@averspec/approvals'

// In an assertion handler:
async function cartMatchesApproval(ctx) {
  const cart = await ctx.getCart()
  await approve(cart) // compares against saved .approved file
}

Objects are serialized as JSON; strings are compared as plain text. When the received value differs from the approved baseline, the test fails with a diff showing exactly what changed.

Visual Approvals

Use approve.visual('name') for screenshot-based pixel comparison. This requires a protocol with screenshotter support (e.g., @averspec/protocol-playwright).

import { approve } from '@averspec/approvals'

// In an assertion handler (with a visual protocol):
async function pageMatchesBaseline(ctx) {
  await approve.visual('checkout-page')
}

Visual approvals capture a screenshot, compare it pixel-by-pixel against the baseline, and allow a small tolerance for subpixel rendering differences.

To create or update baselines for either mode:

AVER_APPROVE=1 npx aver run <test-file>

License

MIT