Set up a test for the failing parsing

helpers.spec.js

@@ -0,0 +1,49 @@
+const { describe, expect, test } = require('@jest/globals');
+const { parse } = require('./helpers');
+
+describe(parse.name, () => {
+  const TEST_DATA = {
+    title: 'test',
+    amount: 1000,
+  };
+
+  [
+    ['number title', { ...TEST_DATA, title: 11 }],
+    ['boolean title', { ...TEST_DATA, title: false }],
+    ['object title', { ...TEST_DATA, title: {} }],
+    ['null title', { ...TEST_DATA, title: null }],
+    ['boolean amount', { ...TEST_DATA, amount: true }],
+    ['object amount', { ...TEST_DATA, amount: {} }],
+  ].forEach(([tag, badData]) => {
+    test(`it rejects ${tag} as bad data`, () => {
+      expect(() => parse(badData)).toThrow();
+    });
+  });
+  test('it accepts a regular value', () => {
+    let result;
+    expect(() => {
+      result = parse(TEST_DATA);
+    }).not.toThrow();
+    expect(result).toEqual(TEST_DATA);
+  });
+  test('it parses yen', () => {
+    let result;
+    expect(() => {
+      result = parse({ title: 'test', amount: '¥3,746'});
+    }).not.toThrow();
+    expect(result).toEqual({
+      amount: 3746,
+      title: 'test',
+    });
+  });
+  test('it strips out non-number values from strings', () => {
+    let result;
+    expect(() => {
+      result = parse({ title: 'test', amount: '¥3,7~4j6.1t1'});
+    }).not.toThrow();
+    expect(result).toEqual({
+      amount: 374611,
+      title: 'test',
+    });
+  });
+});