refactor: centralize task runtime contracts (#199)

src/message-source.test.ts

@@ -1,43 +1,39 @@
 import { describe, expect, it } from 'vitest';
 
 import {
-  isBotMessageSourceKind,
+  inferMessageSourceKindFromBotFlag,
   normalizeMessageSourceKind,
   resolveInjectedMessageSourceKind,
 } from './message-source.js';
+import { DEFAULT_MESSAGE_SOURCE_KIND, MESSAGE_SOURCE_KINDS } from './types.js';
 
-describe('message source helpers', () => {
-  it('defaults IPC injected messages to trusted human-equivalent provenance', () => {
+describe('message source kind helpers', () => {
+  it('uses the canonical source kind list', () => {
+    expect(MESSAGE_SOURCE_KINDS).toEqual([
+      'human',
+      'bot',
+      'trusted_external_bot',
+      'ipc_injected_human',
+      'ipc_injected_bot',
+    ]);
+    expect(DEFAULT_MESSAGE_SOURCE_KIND).toBe('human');
+  });
+
+  it('normalizes unknown source kinds to the default', () => {
+    expect(normalizeMessageSourceKind('trusted_external_bot')).toBe(
+      'trusted_external_bot',
+    );
+    expect(normalizeMessageSourceKind('unknown')).toBe('human');
+  });
+
+  it('derives source kinds from legacy and injected inputs', () => {
+    expect(inferMessageSourceKindFromBotFlag(true)).toBe('bot');
+    expect(inferMessageSourceKindFromBotFlag(false)).toBe('human');
     expect(resolveInjectedMessageSourceKind({ treatAsHuman: true })).toBe(
       'trusted_external_bot',
     );
-    expect(
-      isBotMessageSourceKind(
-        resolveInjectedMessageSourceKind({ treatAsHuman: true }),
-      ),
-    ).toBe(false);
-  });
-
-  it('defaults non-human IPC injected messages to bot-equivalent provenance', () => {
     expect(resolveInjectedMessageSourceKind({ treatAsHuman: false })).toBe(
       'ipc_injected_bot',
     );
-    expect(
-      isBotMessageSourceKind(
-        resolveInjectedMessageSourceKind({ treatAsHuman: false }),
-      ),
-    ).toBe(true);
-  });
-
-  it('honors valid explicit source kinds and normalizes invalid values', () => {
-    expect(
-      resolveInjectedMessageSourceKind({
-        treatAsHuman: true,
-        sourceKind: 'ipc_injected_human',
-      }),
-    ).toBe('ipc_injected_human');
-
-    expect(normalizeMessageSourceKind('bot', 'human')).toBe('bot');
-    expect(normalizeMessageSourceKind('not-real', 'human')).toBe('human');
   });
 });