Build bilingual Astro exchange landing page and brand reference

scripts/quote.test.mjs

@@ -0,0 +1,45 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { calculateQuote, parseAmount } from '../src/lib/quote.ts';
+test('demo calculation deducts the example fee in currency cents', () => {
+  assert.deepEqual(calculateQuote(1, 'BTC', 'EUR'), {
+    rate: 57500,
+    fee: 575,
+    receive: 56925,
+    demo: true,
+  });
+  assert.deepEqual(calculateQuote(2, 'ETH', 'USD'), {
+    rate: 2500,
+    fee: 50,
+    receive: 4950,
+    demo: true,
+  });
+  const q = calculateQuote(123.45, 'USDT', 'EUR');
+  assert.equal(q.fee, 1.14);
+  assert.equal(q.receive, 112.43);
+});
+test('accepts decimal comma and eight crypto decimal places', () => {
+  assert.equal(parseAmount(' 0,25 '), 0.25);
+  assert.equal(parseAmount('0.00000001'), 0.00000001);
+  assert.equal(
+    calculateQuote(parseAmount('0,25'), 'BTC', 'EUR').receive,
+    14231.25,
+  );
+});
+test('rejects ambiguous, malformed, excessive or invalid input', () => {
+  for (const value of [
+    '',
+    '-1',
+    '1e3',
+    '1,2,3',
+    '1.2.3',
+    '<script>',
+    '0.000000001',
+    '1 000',
+  ])
+    assert.ok(Number.isNaN(parseAmount(value)));
+  for (const amount of [0, -1, NaN, Infinity, 1000001])
+    assert.throws(() => calculateQuote(amount, 'BTC', 'EUR'), RangeError);
+  assert.throws(() => calculateQuote(1, 'BOGUS', 'EUR'), RangeError);
+  assert.throws(() => calculateQuote(1, 'BTC', 'BOGUS'), RangeError);
+});