fix(ci): restore unit coverage and contrast audit after R4

scripts/audit-dark-contrast.mjs

@@ -47,6 +47,14 @@ const OUTPUT_PATH = process.env.CONTRAST_AUDIT_OUTPUT || "/tmp/contrast-audit.js
 
 // AGENTS.md 語言代碼: a=# (/), t=#' (/'), h=#: (/:), c=#~ (/~)
 const ROUTES = ["/萌", "/生", "/'食", "/'長褲", "/:客", "/~東西", "/=*", "/@", "/@口", "/about"];
+// CI audits the seeded Miniflare fixture server, where entry paths that match
+// no headword hard-404 (R4): every CI route must be a seeded fixture word
+// (tests/helpers/fixtures.ts — 字 is the only Hakka headword, 黃 the second
+// Mandarin one), one per language prefix the full list covers.
+const CI_FIXTURE_ROUTES = ["/萌", "/黃", "/'食", "/'長褲", "/:字"];
+// First in-dictionary link: the 異體字 icon (.variants-link) is an external link
+// with no tooltip, and on Hakka entries (no radical box) it comes first.
+const HOVER_LINK_SELECTOR = ".result a[href]:not(.variants-link)";
 
 const VIEWPORTS = [
   { name: "desktop", width: 1280, height: 800 },
@@ -55,7 +63,7 @@ const VIEWPORTS = [
 
 const THEMES = ["light", "dark"];
 const CI_MODE = process.argv.includes("--ci") || process.env.CI === "true";
-const AUDIT_ROUTES = CI_MODE ? ROUTES.slice(0, 5) : ROUTES;
+const AUDIT_ROUTES = CI_MODE ? CI_FIXTURE_ROUTES : ROUTES;
 const AUDIT_VIEWPORTS = CI_MODE ? [VIEWPORTS[0], VIEWPORTS[1]] : VIEWPORTS;
 
 // WCAG 2.x contrast thresholds. "Large text" = >=24px, or >=18.66px (14pt)
@@ -756,7 +764,7 @@ async function auditCombo(
     }),
   );
 
-  // 5. Hover first .result a[href] and wait for .ui-tooltip.
+  // 5. Hover the first in-dictionary result link and wait for .ui-tooltip.
   await withIsolatedState(
     browser,
     viewport,
@@ -767,15 +775,15 @@ async function auditCombo(
     actionFailures,
     collectOpts,
     async (page) => {
-      const link = page.locator(".result a[href]").first();
+      const link = page.locator(HOVER_LINK_SELECTOR).first();
       if ((await link.count()) === 0) {
         actionFailures.push({
           route,
           viewport: viewport.name,
           theme,
           state: STATE_HOVER_TOOLTIP,
           kind: "element-missing",
-          selector: ".result a[href]",
+          selector: HOVER_LINK_SELECTOR,
         });
         return false;
       }

scripts/lib/contrast-audit.mjs

@@ -20,7 +20,7 @@ export function classifyActionFailure(failure) {
   const unavailable = new Set([
     'a.iconic-circle.stroke[title="筆順動畫"]',
     ".entry-actions",
-    ".result a[href]",
+    ".result a[href]:not(.variants-link)",
     "#btn-toggle-all-langs",
     "#btn-toggle-import",
   ]);

tests/unit/api-dictionary-nfkc-fallback.test.ts

@@ -15,6 +15,7 @@ import {
   bucketOf,
   handleDictionaryAPI,
   lookupDictionaryEntry,
+  probeDictionaryEntry,
 } from "../../src/api/handleDictionaryAPI";
 
 interface R2Stub {
@@ -76,6 +77,30 @@ describe("bucketOf sanity guard for ⼴ / 广", () => {
   });
 });
 
+describe("probeDictionaryEntry — NFKC fallback decides the entry route's status (R4)", () => {
+  it("returns true when only the NFKC-normalized bucket holds the headword", async () => {
+    const env = makeEnv({
+      [`pack/${IDEOGRAPH_BUCKET}.txt`]: JSON.stringify({ [IDEOGRAPH_KEY]: makeYanEntry() }),
+    });
+    expect(await probeDictionaryEntry(RADICAL_YEN, "a", env)).toBe(true);
+  });
+
+  it("returns false when neither the literal nor the NFKC spelling is a headword", async () => {
+    const env = makeEnv({ [`pack/${IDEOGRAPH_BUCKET}.txt`]: JSON.stringify({}) });
+    expect(await probeDictionaryEntry(RADICAL_YEN, "a", env)).toBe(false);
+  });
+
+  it("returns null (fail open) when the literal bucket shard cannot be parsed", async () => {
+    const env = makeEnv({ [`pack/${RADICAL_BUCKET}.txt`]: "{not json" });
+    expect(await probeDictionaryEntry(RADICAL_YEN, "a", env)).toBeNull();
+  });
+
+  it("returns null (fail open) when the NFKC bucket shard cannot be parsed", async () => {
+    const env = makeEnv({ [`pack/${IDEOGRAPH_BUCKET}.txt`]: "{not json" });
+    expect(await probeDictionaryEntry(RADICAL_YEN, "a", env)).toBeNull();
+  });
+});
+
 describe("lookupDictionaryEntry — Kangxi radical-block fallback", () => {
   it("resolves ⼴ (U+2F34) to the 广 (U+5E7F) entry when only the ideograph bucket is seeded", async () => {
     const env = makeEnv({

tests/unit/dictionary-route.test.ts

@@ -472,6 +472,9 @@ describe("resolveLegacyHashRoute (g0v/moedict-webkit#131)", () => {
   it('does nothing for an empty or bare hash — leaves navbar `href="#"` toggles untouched', () => {
     expect(resolveLegacyHashRoute("/", "")).toBeNull();
     expect(resolveLegacyHashRoute("/", "#")).toBeNull();
+    // A bare language/radical prefix carries no term to route to.
+    expect(resolveLegacyHashRoute("/", "#'")).toBeNull();
+    expect(resolveLegacyHashRoute("/", "#:")).toBeNull();
   });
 
   it("fails closed to null on malformed percent-encoding instead of throwing", () => {
@@ -523,6 +526,15 @@ describe("applyLegacyHashRewrite (boot-time shim before React Router mounts)", (
     window.history.replaceState(null, "", "/");
   });
 
+  it("is a no-op without a DOM (module imported outside the browser)", () => {
+    vi.stubGlobal("window", undefined);
+    try {
+      expect(applyLegacyHashRewrite()).toBe(false);
+    } finally {
+      vi.unstubAllGlobals();
+    }
+  });
+
   it("rewrites /#a=萌 to /萌 via replaceState and clears the hash", () => {
     window.history.replaceState(null, "", "/#a=萌");
     const spy = vi.spyOn(window.history, "replaceState");

tests/unit/worker-dispatch-edges.test.ts

@@ -430,6 +430,20 @@ describe("dispatch — HTML shell fetch returns non-OK", () => {
     expect(res.status).toBe(503);
     expect(res.headers.get("X-Moedict-Shell-Source")).toBe("recovery");
   });
+
+  it("returns a bodyless no-store 404 (not the 503 recovery) for an entry path that misses", async () => {
+    // R4 during a shell outage: the dictionary probe still answers "no such
+    // headword", so the status stays a definitive 404 rather than a recovery
+    // page for a word that does not exist.
+    const fetcher = {
+      fetch: vi.fn(async () => new Response("upstream error", { status: 500 })),
+    };
+    const env = makeEnv({ SITE_ASSETS: fetcher as unknown as AnyEnv["SITE_ASSETS"] });
+    const res = await dispatch(req("/%E8%90%8C"), env);
+    expect(res.status).toBe(404);
+    expect(res.headers.get("Cache-Control")).toBe("no-store");
+    expect(await res.text()).toBe("");
+  });
 });
 
 describe("dispatch — radical 青/靑 variant fallback with neither seeded", () => {
@@ -510,6 +524,19 @@ describe("dispatch — HTML shell metadata injection with dictionary lookup", ()
     expect(await res.text()).toContain("<html");
   });
 
+  it("HEAD on a missed entry path returns the 404 headers without a body", async () => {
+    const fetcher = shellFetcher();
+    const env = makeEnv({ SITE_ASSETS: fetcher as unknown as AnyEnv["SITE_ASSETS"] });
+    const res = await dispatch(
+      new Request("http://localhost/%27%E9%A3%9F", { method: "HEAD" }),
+      env,
+    );
+    expect(res.status).toBe(404);
+    expect(res.headers.get("Cache-Control")).toBe("no-store");
+    expect(res.headers.get("content-type")).toContain("text/html");
+    expect(res.body).toBeNull();
+  });
+
   // Regression (R4 fallout): `/privacy` and `/about` are real client routes,
   // not headwords. Before classifyRoute learned the `privacy` kind, /privacy
   // classified as entry("privacy"), probed as a definitive miss, and a live