SDK-shape conformance test for SearchableIndex (#222)

* test: SDK-shape conformance guard for SearchableIndex (#220)

SearchableIndex is a hand-written interface and indexes.ts force-casts the SDK
index to it with as unknown as, which erases type checking; existing tests only
mock our own interface. So an SDK bump that renames or removes a method the code
calls would slip past the compiler and fail at runtime.

Assert the members the code relies on (describeIndexStats, namespace,
searchRecords, query) exist on a real SDK index handle, constructed offline with
no network. A compile-time assertion was tried but the SDK types the index too
loosely to catch drift without passing vacuously, so this is a runtime check;
verified a renamed member fails it.

* test: assert query/searchRecords on the namespace handle, not top-level (#220 review)

The code calls query and searchRecords through index.namespace(ns) (indexes.ts
namespace(ns).query, search.ts namespace(ns).searchRecords), so probe them on the
namespace handle rather than the top-level index. describeIndexStats/namespace and
the searchRecords index-fallback stay on the top-level index. Confirmed a bogus
namespace-handle member fails the test.

Author: timon0305

src/core/pinecone/searchable-index-conformance.test.ts

@@ -0,0 +1,43 @@
+import { describe, it, expect } from 'vitest';
+import { Pinecone } from '@pinecone-database/pinecone';
+
+/**
+ * SDK-shape conformance guard for SearchableIndex (#220).
+ *
+ * `indexes.ts` force-casts `pc.index(...)` to `SearchableIndex` with `as unknown as`,
+ * which erases type checking, and the other tests only mock our own interface. So
+ * nothing verifies the real SDK index still provides the members the code calls. If a
+ * Pinecone SDK bump renames or removes one, it slips past the compiler and fails at
+ * runtime in production. This asserts those members exist on a real SDK index, so a
+ * drift fails here loudly instead.
+ *
+ * A compile-time assertion was tried but the SDK types the index too loosely to catch
+ * drift, so this is a runtime existence check. `pc.index()` returns a handle
+ * synchronously with no network call, so it needs no live Pinecone.
+ */
+describe('SearchableIndex SDK conformance (#220)', () => {
+  const index = new Pinecone({ apiKey: 'pc-conformance-test' }).index(
+    'conformance-test'
+  ) as unknown as Record<string, unknown>;
+
+  // Called on the top-level index: indexes.ts uses describeIndexStats() and
+  // namespace(), and search.ts uses searchRecords() on the index fallback branch.
+  it.each(['describeIndexStats', 'namespace', 'searchRecords'] as const)(
+    'the SDK index exposes %s()',
+    (method) => {
+      expect(typeof index[method]).toBe('function');
+    }
+  );
+
+  // Called on the namespace handle from index.namespace(ns): indexes.ts does
+  // namespace(ns).query(...) and search.ts does namespace(ns).searchRecords(...).
+  const namespaceHandle = (index.namespace as (name: string) => Record<string, unknown>)(
+    'conformance-test'
+  );
+  it.each(['query', 'searchRecords'] as const)(
+    'the SDK namespace handle exposes %s()',
+    (method) => {
+      expect(typeof namespaceHandle[method]).toBe('function');
+    }
+  );
+});