fix: commit carved wallet funds atomically

src/composables/walletCarveCommit.test.ts

@@ -0,0 +1,130 @@
+import { createPinia, setActivePinia } from 'pinia';
+import { buildNoteUrl } from 'lnurlcash-kit';
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+
+import { deriveBearerAesKey } from '@/lnurlcash/keys';
+import type { CarveResult } from '@/lnurlcash/ops';
+import { loadBearers } from '@/lnurlcash/storage';
+import { stubLocalStorage } from '@/lnurlcash/test-utils';
+import type { NewBearer } from '@/lnurlcash/types';
+import { commitCarve } from './walletCarveCommit';
+import { useWalletStore } from '../stores/wallet';
+
+const note = (secret: string): NewBearer => ({
+  url: buildNoteUrl('https://mint.example/w', secret.repeat(32), 21_000),
+  callback: 'https://mint.example/w/cb',
+  amount: 21_000,
+  verified: true,
+});
+
+const failOnBearerWrite = (occurrence: number): void => {
+  const setItem = localStorage.setItem.bind(localStorage);
+  let writes = 0;
+  vi.spyOn(localStorage, 'setItem').mockImplementation((key, value) => {
+    if (key === 'sattle_bearers') {
+      writes += 1;
+      if (writes === occurrence) throw new Error('bearer storage unavailable');
+    }
+    setItem(key, value);
+  });
+};
+
+beforeEach(() => {
+  vi.restoreAllMocks();
+  vi.unstubAllGlobals();
+  vi.stubGlobal('navigator', {});
+  stubLocalStorage();
+  setActivePinia(createPinia());
+});
+
+describe('commitCarve', () => {
+  it('commits the carve additions and spent marks in one bearer write', async () => {
+    // Given a wallet holding the carve's input note
+    const wallet = useWalletStore();
+    await wallet.create();
+    const ownerFence = wallet.captureOwnerFence();
+    const [input] = await wallet.addBearers([note('aa')], ownerFence);
+    if (!input) throw new Error('Expected the input bearer.');
+    const carve: CarveResult = {
+      note: note('bb'),
+      change: note('cc'),
+      consumed: [input],
+    };
+    const writes = vi.spyOn(localStorage, 'setItem');
+
+    // When the carve is committed
+    const committed = await commitCarve(wallet, carve, {
+      ownerFence,
+      warn: () => undefined,
+    });
+
+    // Then the whole rotation landed as ONE durable write
+    expect(writes.mock.calls.filter(([key]) => key === 'sattle_bearers')).toHaveLength(1);
+    expect(committed.url).toBe(carve.note.url);
+    expect(wallet.bearers).toHaveLength(3);
+    expect(wallet.bearers.find((bearer) => bearer.id === input.id)?.spent).toBe(true);
+    const key = await deriveBearerAesKey(wallet.requireLinkingKey());
+    const persisted = await loadBearers(key);
+    expect(persisted).toHaveLength(3);
+    expect(persisted.find((bearer) => bearer.id === input.id)?.spent).toBe(true);
+  });
+
+  it('survives a failure that would have hit the old split commit second write', async () => {
+    // Given a wallet holding the carve's input note, with the second
+    // sattle_bearers write poisoned (the old add-then-markSpent split wrote
+    // twice; the single-write commit never reaches a second write)
+    const wallet = useWalletStore();
+    await wallet.create();
+    const ownerFence = wallet.captureOwnerFence();
+    const [input] = await wallet.addBearers([note('aa')], ownerFence);
+    if (!input) throw new Error('Expected the input bearer.');
+    failOnBearerWrite(2);
+    const carve: CarveResult = {
+      note: note('bb'),
+      change: note('cc'),
+      consumed: [input],
+    };
+
+    // When the carve is committed
+    const committed = await commitCarve(wallet, carve, {
+      ownerFence,
+      warn: () => undefined,
+    });
+
+    // Then the rotation committed completely: additions tracked, input spent
+    expect(committed.url).toBe(carve.note.url);
+    expect(wallet.bearers).toHaveLength(3);
+    expect(wallet.bearers.find((bearer) => bearer.id === input.id)?.spent).toBe(true);
+    const key = await deriveBearerAesKey(wallet.requireLinkingKey());
+    const persisted = await loadBearers(key);
+    expect(persisted).toHaveLength(3);
+    expect(persisted.find((bearer) => bearer.id === input.id)?.spent).toBe(true);
+  });
+
+  it('leaves no partial carve behind when the commit write itself fails', async () => {
+    // Given bearer storage that fails the very next write
+    const wallet = useWalletStore();
+    await wallet.create();
+    const ownerFence = wallet.captureOwnerFence();
+    const [input] = await wallet.addBearers([note('aa')], ownerFence);
+    if (!input) throw new Error('Expected the input bearer.');
+    failOnBearerWrite(1);
+
+    // When the carve commit fails
+    await expect(
+      commitCarve(
+        wallet,
+        { note: note('bb'), change: note('cc'), consumed: [input] },
+        { ownerFence, warn: () => undefined },
+      ),
+    ).rejects.toThrow('bearer storage unavailable');
+
+    // Then nothing moved: not in storage, not in the reactive list
+    expect(wallet.bearers).toHaveLength(1);
+    expect(wallet.bearers[0]?.spent).toBeUndefined();
+    const key = await deriveBearerAesKey(wallet.requireLinkingKey());
+    const persisted = await loadBearers(key);
+    expect(persisted).toHaveLength(1);
+    expect(persisted[0]?.spent).toBeUndefined();
+  });
+});