grep -rn 'refund\|Refund\|REFUND' --include='*.{ts,js,py,java,go,rb,cs}' .

test('full refund', async () => {
  const intent = await createSucceededIntent({ amount: 1000 });
  const refund = await stripe.refunds.create({ payment_intent: intent.id });
  expect(refund.status).toBe('succeeded');
  expect(refund.amount).toBe(1000);
});

test('partial refund', async () => {
  const intent = await createSucceededIntent({ amount: 1000 });
  const refund = await stripe.refunds.create({ payment_intent: intent.id, amount: 500 });
  expect(refund.amount).toBe(500);
});

test('over-refund rejected', async () => {
  const intent = await createSucceededIntent({ amount: 1000 });
  await expect(
    stripe.refunds.create({ payment_intent: intent.id, amount: 1500 })
  ).rejects.toThrow(/refund_amount_exceeds_charge_amount/);
});

const result = await checkout.modificationsCorrespondingRefund({
  originalReference: 'capture-pspReference',
  modificationAmount: { value: 500, currency: 'EUR' },
});
expect(result.response).toBe('[refund-received]');
// Actual refund completion via webhook (notification)

const request = new paypal.payments.CapturesRefundRequest(captureId);
request.requestBody({ amount: { value: '5.00', currency_code: 'USD' } });
const result = await client.execute(request);
expect(result.result.status).toBe('COMPLETED');

const result = await gateway.transaction.refund(transactionId, '5.00');
expect(result.success).toBe(true);
expect(result.transaction.type).toBe('credit');

# tests/payment/refund-matrix.yaml
matrix:
  gateways:
    - stripe
    - adyen
    - paypal
    - braintree
  variants:
    - full
    - partial
    - multiple-partials
    - over-refund-attempt
    - already-refunded
    - failed-charge
    - disputed-charge
  timing:
    - immediate
    - async-webhook

// tests/payment/refund-stripe.test.ts
import { CASES } from './refund-matrix';

describe.each(CASES.stripe)('Stripe refund: $variant', ({ variant, expected }) => {
  test(variant, async () => {
    // ... per-variant logic + assertion
  });
});

test('idempotent refund', async () => {
  const intent = await createSucceededIntent({ amount: 1000 });
  const key = 'refund-' + intent.id;

  const r1 = await stripe.refunds.create({ payment_intent: intent.id, amount: 500 }, { idempotencyKey: key });
  const r2 = await stripe.refunds.create({ payment_intent: intent.id, amount: 500 }, { idempotencyKey: key });

  expect(r1.id).toBe(r2.id);
});

## Refund Coverage Matrix

| Gateway | Variant | Immediate | Async Webhook |
|---|---|---|---|
| Stripe | full | ✅ | n/a (sync) |
| Stripe | partial | ✅ | n/a |
| Stripe | over-refund | ✅ | n/a |
| Adyen | full | ✅ | ✅ |
| ... | ... | ... | ... |

## Documented gaps

- Braintree disputed-charge refund: deferred to phase 2
- Multi-partial refund crossing day boundaries: manual QA