[Init] Initial commit - NetMesh terminal manager

application/state/settingsChromeStore.test.ts

@@ -0,0 +1,170 @@
+import assert from 'node:assert/strict';
+import { readFileSync } from 'node:fs';
+import test from 'node:test';
+
+import {
+  DEFAULT_SETTINGS_CHROME_SNAPSHOT,
+  getSettingsChromeActions,
+  getSettingsChromeSnapshot,
+  publishSettingsChromeSnapshot,
+  registerSettingsChromeActions,
+  settingsChromeSnapshotsEqual,
+  subscribeSettingsChrome,
+  subscribeSettingsChromeActions,
+  type SettingsChromeSnapshot,
+} from './settingsChromeStore.ts';
+
+type SnapshotKey = keyof SettingsChromeSnapshot;
+
+/**
+ * Derive the probe value instead of hard-coding a field list: the chrome slice
+ * grows as surfaces move off the App settings bag, and this suite is about the
+ * dedupe contract, not about which fields happen to be in it today.
+ */
+function mutate(value: unknown): unknown {
+  if (typeof value === 'boolean') return !value;
+  if (typeof value === 'number') return value + 1;
+  if (typeof value === 'string') return `${value}-changed`;
+  throw new Error(`Unsupported snapshot field type: ${typeof value}`);
+}
+
+test('settingsChromeStore ignores structurally identical republishes', () => {
+  const base = getSettingsChromeSnapshot();
+  let events = 0;
+  const unsubscribe = subscribeSettingsChrome(() => {
+    events += 1;
+  });
+
+  // useSettingsState rebuilds this object literal on every render, so a fresh
+  // identity with unchanged fields must not wake chrome consumers.
+  publishSettingsChromeSnapshot({ ...base });
+  publishSettingsChromeSnapshot({ ...base });
+  assert.equal(events, 0);
+  assert.equal(getSettingsChromeSnapshot(), base);
+
+  unsubscribe();
+});
+
+test('settingsChromeStore notifies on any single chrome field change', () => {
+  const base = getSettingsChromeSnapshot();
+  const keys = Object.keys(base) as SnapshotKey[];
+  assert.ok(keys.length > 0, 'chrome snapshot must publish at least one field');
+
+  for (const key of keys) {
+    let events = 0;
+    const unsubscribe = subscribeSettingsChrome(() => {
+      events += 1;
+    });
+
+    const changed = { ...base, [key]: mutate(base[key]) } as SettingsChromeSnapshot;
+    publishSettingsChromeSnapshot(changed);
+    assert.equal(events, 1, `expected a notification for ${key}`);
+    assert.equal(getSettingsChromeSnapshot()[key], changed[key]);
+
+    publishSettingsChromeSnapshot({ ...changed });
+    assert.equal(events, 1, `expected no repeat notification for ${key}`);
+
+    publishSettingsChromeSnapshot(base);
+    assert.equal(events, 2, `expected a restore notification for ${key}`);
+
+    unsubscribe();
+  }
+
+  assert.equal(getSettingsChromeSnapshot(), base);
+});
+
+test('settingsChromeStore stops notifying after unsubscribe', () => {
+  const base = getSettingsChromeSnapshot();
+  const [firstKey] = Object.keys(base) as SnapshotKey[];
+  let events = 0;
+  const unsubscribe = subscribeSettingsChrome(() => {
+    events += 1;
+  });
+
+  unsubscribe();
+  publishSettingsChromeSnapshot({
+    ...base,
+    [firstKey]: mutate(base[firstKey]),
+  } as SettingsChromeSnapshot);
+  assert.equal(events, 0);
+
+  publishSettingsChromeSnapshot(base);
+});
+
+test('chrome snapshot fields stay in sync with what useSettingsState publishes', () => {
+  // The whole point of the slice is that chrome leaves can stop reading the
+  // App settings bag. A field the publisher forgets would silently freeze at
+  // its default, so pin the two shapes together.
+  const source = readFileSync(new URL('./useSettingsState.ts', import.meta.url), 'utf8');
+  const callStart = source.indexOf('publishSettingsChromeSnapshot({');
+  assert.notEqual(callStart, -1, 'useSettingsState must publish the chrome slice');
+  const callEnd = source.indexOf('});', callStart);
+  assert.notEqual(callEnd, -1);
+
+  const published = source
+    .slice(callStart, callEnd)
+    .split('\n')
+    .slice(1)
+    .map((line) => line.trim().match(/^([A-Za-z0-9_]+)\s*[:,]/)?.[1])
+    .filter((name): name is string => Boolean(name));
+
+  assert.deepEqual(
+    published.slice().sort(),
+    Object.keys(DEFAULT_SETTINGS_CHROME_SNAPSHOT).sort(),
+  );
+});
+
+test('settingsChromeSnapshotsEqual compares by field, not object identity', () => {
+  const base = DEFAULT_SETTINGS_CHROME_SNAPSHOT;
+  assert.equal(settingsChromeSnapshotsEqual({ ...base }, { ...base }), true);
+  assert.equal(
+    settingsChromeSnapshotsEqual(base, { ...base, windowOpacity: 0.8 }),
+    false,
+  );
+  assert.equal(
+    settingsChromeSnapshotsEqual(base, { ...base, showSftpTab: !base.showSftpTab }),
+    false,
+  );
+});
+
+test('registerSettingsChromeActions exposes the theme and opacity setters', () => {
+  const calls: string[] = [];
+  let actionEvents = 0;
+  const unsubscribe = subscribeSettingsChromeActions(() => {
+    actionEvents += 1;
+  });
+
+  registerSettingsChromeActions({
+    setTheme: () => calls.push('theme'),
+    setWindowOpacity: () => calls.push('opacity'),
+  });
+
+  const actions = getSettingsChromeActions();
+  assert.ok(actions);
+  actions.setTheme('light');
+  actions.setWindowOpacity(0.5);
+  assert.deepEqual(calls, ['theme', 'opacity']);
+  assert.equal(actionEvents, 1);
+
+  registerSettingsChromeActions(null);
+  assert.equal(getSettingsChromeActions(), null);
+  assert.equal(actionEvents, 2);
+
+  unsubscribe();
+});
+
+test('setter churn never invalidates the chrome value snapshot', () => {
+  // useSettingsState re-registers on every setter identity change; chrome
+  // consumers of the value snapshot must not re-render for that.
+  let valueEvents = 0;
+  const unsubscribe = subscribeSettingsChrome(() => {
+    valueEvents += 1;
+  });
+
+  registerSettingsChromeActions({ setTheme: () => {}, setWindowOpacity: () => {} });
+  registerSettingsChromeActions({ setTheme: () => {}, setWindowOpacity: () => {} });
+  assert.equal(valueEvents, 0);
+
+  registerSettingsChromeActions(null);
+  unsubscribe();
+});