Fix loading of recommended methods

tests/unit/facetRecommendationsLoad.test.ts

@@ -0,0 +1,54 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+import {
+  buildFacetRecommendationRequestKey,
+  getCachedFacetScores,
+  loadFacetScores,
+} from "../../lib/create/facetRecommendationsLoad";
+
+describe("loadFacetScores", () => {
+  beforeEach(() => {
+    vi.stubGlobal(
+      "fetch",
+      vi.fn().mockResolvedValue({
+        ok: true,
+        json: async () => ({
+          methods: [
+            { slug: "slack", matches: { score: 3 } },
+            { slug: "email", matches: { score: 1 } },
+          ],
+        }),
+      }),
+    );
+  });
+
+  afterEach(() => {
+    vi.unstubAllGlobals();
+  });
+
+  it("caches scores by section and facet query", async () => {
+    const queryString = "facet.size=small";
+    const scores = await loadFacetScores("communication", queryString);
+
+    expect(scores).toEqual({ slack: 3, email: 1 });
+    expect(
+      getCachedFacetScores(
+        buildFacetRecommendationRequestKey("communication", queryString),
+      ),
+    ).toEqual(scores);
+    expect(fetch).toHaveBeenCalledTimes(1);
+
+    await loadFacetScores("communication", queryString);
+    expect(fetch).toHaveBeenCalledTimes(1);
+  });
+
+  it("dedupes in-flight requests for the same key", async () => {
+    const queryString = "facet.size=small";
+    const [a, b] = await Promise.all([
+      loadFacetScores("membership", queryString),
+      loadFacetScores("membership", queryString),
+    ]);
+
+    expect(a).toEqual(b);
+    expect(fetch).toHaveBeenCalledTimes(1);
+  });
+});