"Get everything into feature files" - including the retry helper

Problem Description

We run two kinds of tests in this repo. features/refunds.feature describes the refund policy; our finance lead reads it in every sprint review and has edited it twice herself when the policy changed. test/retry.test.js covers the backoff maths in @acme/retry, an internal package that our own services import - it has no UI, no customer, and nobody outside the four backend engineers has ever opened that file.

Two things landed on us this week.

Finance signed off a new rule: orders in the digital category are never refundable, whatever their age. src/refund-policy.js already implements it. The feature file does not mention it.

Separately, our engineering manager saw the refund feature in a review, liked how readable it was, and asked us to "get everything into feature files so the whole suite reads the same way", naming test/retry.test.js specifically. He has not worked with these tools before and asked us to come back with the change and a short note on how it went.

Output Specification

1. Cover the new digital-order rule so that it lands in the file finance reads. Reuse the step vocabulary already in features/step_definitions/refund.steps.js wherever the sentence exists; add step code only for what is genuinely new.
2. Deliver whatever you conclude is the right end state for test/retry.test.js, and include, in no more than three sentences, the reason it takes that shape. Address the note to the manager - he will read it and act on it.
3. Everything under src/ is production code and must not change.
4. Whatever you deliver, the backoff behaviour that test/retry.test.js covers today must still be covered when you are done.

Input Files

Extract the following files before beginning.

=============== FILE: features/refunds.feature =============== Feature: Refund policy

Scenario: Full refund inside thirty days Given a delivered order worth $80.00 in the "books" category When a refund is requested 10 days later Then the refund is approved for $80.00

Scenario: Half refund in the second month Given a delivered order worth $80.00 in the "books" category When a refund is requested 45 days later Then the refund is approved for $40.00

Scenario: Nothing after sixty days Given a delivered order worth $80.00 in the "books" category When a refund is requested 90 days later Then the refund is refused because "Outside the refund window"

=============== FILE: features/step_definitions/refund.steps.js =============== const assert = require('node:assert'); const { Given, When, Then } = require('@cucumber/cucumber'); const { refundFor, DAY } = require('../../src/refund-policy');

Given('a delivered order worth ${float} in the {string} category', function (total, category) { this.order = { total, category, deliveredAt: 0 }; });

When('a refund is requested {int} days later', function (days) { this.decision = refundFor(this.order, days * DAY); });

Then('the refund is approved for ${float}', function (amount) { assert.strictEqual(this.decision.approved, true); assert.strictEqual(this.decision.amount, amount); });

Then('the refund is refused because {string}', function (reason) { assert.strictEqual(this.decision.approved, false); assert.strictEqual(this.decision.reason, reason); });

=============== FILE: src/refund-policy.js =============== const DAY = 24 * 60 * 60 * 1000;

function refundFor(order, requestedAfter) { if (order.category === 'digital') { return { approved: false, reason: 'Digital orders are final' }; } if (requestedAfter <= 30 * DAY) { return { approved: true, amount: order.total }; } if (requestedAfter <= 60 * DAY) { return { approved: true, amount: Number((order.total * 0.5).toFixed(2)) }; } return { approved: false, reason: 'Outside the refund window' }; }

module.exports = { refundFor, DAY };

=============== FILE: src/retry.js =============== function backoff(attempt, { base = 100, cap = 2000, jitter = 0 } = {}) { const raw = Math.min(cap, base * 2 ** (attempt - 1)); return Math.round(raw * (1 - jitter)); }

module.exports = { backoff };

=============== FILE: test/retry.test.js =============== const test = require('node:test'); const assert = require('node:assert'); const { backoff } = require('../src/retry');

test('doubles the delay on each attempt', () => { assert.strictEqual(backoff(1), 100); assert.strictEqual(backoff(2), 200); assert.strictEqual(backoff(3), 400); });

test('never exceeds the cap', () => { assert.strictEqual(backoff(9), 2000); });

test('jitter reduces the delay proportionally', () => { assert.strictEqual(backoff(2, { jitter: 0.25 }), 150); });

=============== FILE: cucumber.js =============== module.exports = { default: { require: ['features/step_definitions/**/*.js'], format: ['progress'], }, };

=============== FILE: package.json =============== { "name": "acme-billing", "private": true, "scripts": { "bdd": "cucumber-js", "test": "node --test test/" }, "devDependencies": { "@cucumber/cucumber": "^10.9.0" } }