cinny/src/app/state/translation.test.ts

import { test } from 'node:test';
import assert from 'node:assert/strict';

// The module evaluates atomWithStorage(..., { getOnInit: true }) which reads
// localStorage at load time. node has none — install a no-op mock, then import
// dynamically (a static import would hoist above the mock).
(globalThis as { localStorage?: unknown }).localStorage = {
  getItem: () => null,
  setItem: () => undefined,
  removeItem: () => undefined,
};

const { addTranslation, findTranslation, makeCacheKey } = await import('./translation');

const entry = (key: string, translated = `t-${key}`, fromLang = 'de') => ({
  key,
  translated,
  fromLang,
});

test('makeCacheKey: eventId + normalized target + content fingerprint', () => {
  // Same event + target + text is stable and prefixed by event:normalizedTarget.
  const k1 = makeCacheKey('$abc', 'en-US', 'hola');
  const k2 = makeCacheKey('$abc', 'EN', 'hola');
  assert.equal(k1, k2);
  assert.ok(k1.startsWith('$abc:en:'));
  // Different body (an edit) => different key, so a stale translation misses.
  assert.notEqual(makeCacheKey('$abc', 'en', 'hola'), makeCacheKey('$abc', 'en', 'adios'));
  // Missing text arg still yields a stable key.
  assert.ok(makeCacheKey('$abc', 'en').startsWith('$abc:en:'));
});

test('addTranslation: prepends, newest first', () => {
  const out = addTranslation([entry('a'), entry('b')], entry('c'));
  assert.deepEqual(
    out.map((e) => e.key),
    ['c', 'a', 'b'],
  );
});

test('addTranslation: de-dupes by key, moving to front (and updates value)', () => {
  const out = addTranslation([entry('a', 'old'), entry('b')], entry('a', 'new'));
  assert.deepEqual(
    out.map((e) => e.key),
    ['a', 'b'],
  );
  assert.equal(out[0].translated, 'new');
});

test('addTranslation: caps at max (newest kept)', () => {
  const out = addTranslation([entry('a'), entry('b'), entry('c')], entry('d'), 3);
  assert.deepEqual(
    out.map((e) => e.key),
    ['d', 'a', 'b'],
  );
});

test('addTranslation: ignores empty key or translated', () => {
  const start = [entry('a')];
  assert.equal(addTranslation(start, entry('', 'x')), start);
  assert.equal(addTranslation(start, entry('b', '')), start);
});

test('findTranslation: returns match or undefined', () => {
  const list = [entry('a'), entry('b')];
  assert.equal(findTranslation(list, 'b')?.key, 'b');
  assert.equal(findTranslation(list, 'z'), undefined);
});