feat: Security

toju-app/src/app/domains/chat/domain/rules/message-revision.builder.rules.spec.ts

@@ -0,0 +1,94 @@
+import {
+  describe,
+  it,
+  expect
+} from 'vitest';
+import type { Message } from '../../../../shared-kernel';
+import {
+  buildMessageRevision,
+  materializeMessageFromRevision,
+  revisionBeatsMessage
+} from './message-revision.builder.rules';
+
+function createMessage(overrides: Partial<Message> = {}): Message {
+  return {
+    id: 'message-1',
+    roomId: 'room-1',
+    senderId: 'user-1',
+    senderName: 'User 1',
+    content: 'hello',
+    timestamp: 1_000,
+    reactions: [],
+    isDeleted: false,
+    ...overrides
+  };
+}
+
+describe('message-revision.builder.rules', () => {
+  it('builds create revisions at revision zero', async () => {
+    const message = createMessage();
+    const revision = await buildMessageRevision({
+      message,
+      type: 'create',
+      actorId: 'user-1',
+      editedAt: 1_000
+    });
+
+    expect(revision.revision).toBe(0);
+    expect(revision.headHash).toMatch(/^[a-f0-9]{64}$/);
+    expect(revision.type).toBe('create');
+  });
+
+  it('increments revision for author edits', async () => {
+    const message = createMessage({ revision: 0, headHash: 'abc' });
+    const revision = await buildMessageRevision({
+      message,
+      type: 'author-edit',
+      actorId: 'user-1',
+      content: 'edited',
+      editedAt: 2_000,
+      prevRevisionHash: 'abc'
+    });
+
+    expect(revision.revision).toBe(1);
+    expect(revision.prevRevisionHash).toBe('abc');
+    expect(revision.content).toBe('edited');
+  });
+
+  it('materializes message state from a revision', async () => {
+    const revision = await buildMessageRevision({
+      message: createMessage(),
+      type: 'author-edit',
+      actorId: 'user-1',
+      content: 'edited',
+      editedAt: 2_000
+    });
+    const materialized = materializeMessageFromRevision(createMessage(), revision);
+
+    expect(materialized.revision).toBe(1);
+    expect(materialized.content).toBe('edited');
+    expect(materialized.headHash).toBe(revision.headHash);
+  });
+
+  it('detects when a revision should replace local state', async () => {
+    const local = materializeMessageFromRevision(
+      createMessage({ revision: 0, headHash: 'old' }),
+      await buildMessageRevision({
+        message: createMessage(),
+        type: 'create',
+        actorId: 'user-1',
+        editedAt: 1_000
+      })
+    );
+    const incoming = await buildMessageRevision({
+      message: createMessage({ revision: 0, headHash: local.headHash }),
+      type: 'author-edit',
+      actorId: 'user-1',
+      content: 'edited',
+      editedAt: 2_000,
+      prevRevisionHash: local.headHash ?? ''
+    });
+
+    expect(revisionBeatsMessage(incoming, local)).toBe(true);
+  });
+});