Address Claude review feedback

src/core/services/frequency-dictionary-service.test.ts

@@ -0,0 +1,49 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import fs from "node:fs";
+import os from "node:os";
+import path from "node:path";
+
+import { createFrequencyDictionaryLookupService } from "./frequency-dictionary-service";
+
+test("createFrequencyDictionaryLookupService logs parse errors and returns no-op for invalid dictionaries", async () => {
+  const logs: string[] = [];
+  const tempDir = fs.mkdtempSync(path.join(os.tmpdir(), "subminer-frequency-dict-"));
+  const bankPath = path.join(tempDir, "term_meta_bank_1.json");
+  fs.writeFileSync(bankPath, "{ invalid json");
+
+  const lookup = await createFrequencyDictionaryLookupService({
+    searchPaths: [tempDir],
+    log: (message) => {
+      logs.push(message);
+    },
+  });
+
+  const rank = lookup("猫");
+
+  assert.equal(rank, null);
+  assert.equal(
+    logs.some((entry) =>
+      entry.includes("Failed to parse frequency dictionary file as JSON") &&
+      entry.includes("term_meta_bank_1.json")
+    ),
+    true,
+  );
+});
+
+test("createFrequencyDictionaryLookupService continues with no-op lookup when search path is missing", async () => {
+  const logs: string[] = [];
+  const missingPath = path.join(os.tmpdir(), "subminer-frequency-dict-missing-dir");
+  const lookup = await createFrequencyDictionaryLookupService({
+    searchPaths: [missingPath],
+    log: (message) => {
+      logs.push(message);
+    },
+  });
+
+  assert.equal(lookup("猫"), null);
+  assert.equal(
+    logs.some((entry) => entry.includes(`Frequency dictionary not found.`)),
+    true,
+  );
+});