Bound inference result cache

tests/cache.test.ts

@@ -0,0 +1,41 @@
+import { describe, expect, it } from "vitest";
+import { ResultCache } from "../src/inference/cache";
+import type { InferenceResult } from "../src/shared/types";
+
+const result = (id: string): InferenceResult => ({
+  requestId: id,
+  id,
+  textHash: id,
+  label: "toxic",
+  probability: .9,
+  navigationId: "nav"
+});
+
+describe("ResultCache", () => {
+  it("evicts the oldest entry when the cache reaches its limit", () => {
+    const cache = new ResultCache(2);
+
+    cache.set("first", result("first"));
+    cache.set("second", result("second"));
+    cache.set("third", result("third"));
+
+    expect(cache.size).toBe(2);
+    expect(cache.get("first")).toBeUndefined();
+    expect(cache.get("second")?.id).toBe("second");
+    expect(cache.get("third")?.id).toBe("third");
+  });
+
+  it("uses normalized text for bounded cache entries", () => {
+    const cache = new ResultCache(1);
+
+    cache.set("  Same   text ", result("same"));
+
+    expect(cache.get("same text")?.id).toBe("same");
+    expect(cache.size).toBe(1);
+  });
+
+  it("rejects invalid cache sizes", () => {
+    expect(() => new ResultCache(0)).toThrow();
+    expect(() => new ResultCache(1.5)).toThrow();
+  });
+});