refactor(catalog): review cleanup — drop dead fetchModelList, dedupe helpers

Post-review of PR #8:
- remove fetchModelList (no remaining callers after server.ts migrated
  to refreshCatalog)
- extract displayNameFor() to collapse the three display-name fallback
  chains in catalog.ts
- share the URL-filtering CC models fetch mock between test files via
  tests/helpers.ts

Co-Authored-By: Claude <noreply@anthropic.com>

Author: thaolaptrinh

src/translate/catalog.ts

@@ -45,11 +45,16 @@ function buildCatalog(models: CatalogModel[]): ModelCatalog {
   };
 }
 
+/** Best display name: API name → static name → bare last path segment. */
+function displayNameFor(id: string, apiName?: string): string {
+  return apiName ?? STATIC_NAMES[id] ?? id.split("/").pop() ?? id;
+}
+
 export function getStaticCatalog(): ModelCatalog {
   return buildCatalog(
     STATIC_BUILTIN.map((id) => ({
       id,
-      displayName: STATIC_NAMES[id] ?? id.split("/").pop() ?? id,
+      displayName: displayNameFor(id),
       contextWindow: STATIC_CONTEXT[id] ?? 128_000,
       source: "static" as const,
     })),
@@ -120,7 +125,7 @@ export async function refreshCatalog(
           const api = apiById.get(id);
           merged.push({
             id,
-            displayName: api?.name ?? STATIC_NAMES[id] ?? id.split("/").pop() ?? id,
+            displayName: displayNameFor(id, api?.name),
             contextWindow: api?.context_length ?? STATIC_CONTEXT[id] ?? 128_000,
             source: api ? "api" : "static",
           });
@@ -130,7 +135,7 @@ export async function refreshCatalog(
           if (seen.has(m.id)) continue;
           merged.push({
             id: m.id,
-            displayName: m.name ?? m.id.split("/").pop() ?? m.id,
+            displayName: displayNameFor(m.id, m.name),
             contextWindow: m.context_length ?? 128_000,
             source: "api",
           });

src/translate/models.ts

@@ -1,7 +1,7 @@
 // Model resolution, aliasing, and discovery against the CC provider API.
 
 import modelsData from "@/models.json" with { type: "json" };
-import { getCatalog, refreshCatalog } from "@/translate/catalog.js";
+import { getCatalog } from "@/translate/catalog.js";
 
 const BUILTIN_MODELS: string[] = modelsData.builtin;
 const SHORT_ALIASES: Record<string, string> = modelsData.shortAliases;
@@ -11,16 +11,6 @@ const REASONING_EFFORTS: Record<string, string[]> = modelsData.reasoningEfforts
 /** Rank ordering of effort levels (low → max). Used to clip to the nearest valid. */
 const EFFORT_RANK: Record<string, number> = { low: 0, medium: 1, high: 2, xhigh: 3, max: 4 };
 
-/**
- * Fetch available open-source models from the CC provider API (closed models
- * are filtered out) and merge them into the catalog. Returns the merged model
- * list. Failures keep the current (static fallback) catalog.
- */
-export async function fetchModelList(apiBase: string, apiKey: string): Promise<string[]> {
-  const catalog = await refreshCatalog(apiBase, apiKey);
-  return catalog.ids;
-}
-
 export function getDefaultModels(): string[] {
   return getCatalog().ids;
 }

tests/catalog.test.ts

@@ -9,24 +9,12 @@ import {
 import { resolveModel } from "@/translate/models.js";
 import { loadConfig } from "@/config.js";
 import { createServer } from "@/server.js";
+import { mockCcModelsFetch } from "./helpers.js";
 
 const API_BASE = "https://api.test-cc.example";
 const API_KEY = "test-key";
 
-function mockFetch(models: unknown, calls: { count: number } = { count: 0 }) {
-  const realFetch = globalThis.fetch.bind(globalThis);
-  return vi.spyOn(globalThis, "fetch").mockImplementation(async (input, init) => {
-    const url = typeof input === "string" ? input : (input as Request).url ?? String(input);
-    // Only intercept CC API calls; other fetches (e.g. hitting the test server
-    // itself) must go to the real network stack.
-    if (!url.includes("/provider/v1/models")) return realFetch(input, init);
-    calls.count += 1;
-    return new Response(JSON.stringify({ object: "list", data: models }), {
-      status: 200,
-      headers: { "Content-Type": "application/json" },
-    }) as unknown as Response;
-  });
-}
+const mockFetch = mockCcModelsFetch;
 
 const API_MODELS = [
   { id: "claude-opus-5", name: "Claude Opus 5", context_length: 1000000 },

tests/helpers.ts

@@ -0,0 +1,20 @@
+import { vi } from "vitest";
+
+/**
+ * Mock only the CC provider models endpoint. Other fetches (e.g. requests to
+ * the test server itself) must reach the real network stack — a blanket fetch
+ * mock silently swallows them and the test reads the mock payload instead of
+ * the server's actual response.
+ */
+export function mockCcModelsFetch(models: unknown, calls: { count: number } = { count: 0 }) {
+  const realFetch = globalThis.fetch.bind(globalThis);
+  return vi.spyOn(globalThis, "fetch").mockImplementation(async (input, init) => {
+    const url = typeof input === "string" ? input : (input as Request).url ?? String(input);
+    if (!url.includes("/provider/v1/models")) return realFetch(input, init);
+    calls.count += 1;
+    return new Response(JSON.stringify({ object: "list", data: models }), {
+      status: 200,
+      headers: { "Content-Type": "application/json" },
+    }) as unknown as Response;
+  });
+}

tests/setup-opencode.test.ts

@@ -1,6 +1,7 @@
 import { describe, test, expect, beforeEach, afterEach, vi } from "vitest";
 import { setupOpenCodeConfig } from "@/setup/opencode.js";
 import { __resetCatalogForTests } from "@/translate/catalog.js";
+import { mockCcModelsFetch } from "./helpers.js";
 import fs from "node:fs";
 
 // Never hit the real CC API or read the developer's saved auth during tests.
@@ -64,21 +65,10 @@ describe("setupOpenCodeConfig", () => {
   test("builds config from the live API catalog when a key is available", async () => {
     process.env.CC_API_KEY = "test-key";
     process.env.CC_API_BASE = "https://api.test-cc.example";
-    const realFetch = globalThis.fetch.bind(globalThis);
-    vi.spyOn(globalThis, "fetch").mockImplementation(async (input, init) => {
-      const url = typeof input === "string" ? input : (input as Request).url ?? String(input);
-      if (!url.includes("/provider/v1/models")) return realFetch(input, init);
-      return new Response(
-        JSON.stringify({
-          object: "list",
-          data: [
-            { id: "claude-opus-5", name: "Claude Opus 5", context_length: 1000000 },
-            { id: "zai-org/GLM-5.3", name: "GLM-5.3", context_length: 1000000 },
-          ],
-        }),
-        { status: 200 },
-      ) as unknown as Response;
-    });
+    mockCcModelsFetch([
+      { id: "claude-opus-5", name: "Claude Opus 5", context_length: 1000000 },
+      { id: "zai-org/GLM-5.3", name: "GLM-5.3", context_length: 1000000 },
+    ]);
 
     await setupOpenCodeConfig("local");
     const config = JSON.parse(written as string);