test(tts): add Azure TTS provider tests

- Test voice list mapping from Azure API response
- Test filtering of deprecated voices
- Test error handling for API failures
- Test custom baseUrl support

src/tts/providers/azure.test.ts

@@ -0,0 +1,125 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { listAzureVoices } from "./azure.js";
+
+describe("listAzureVoices", () => {
+  const originalFetch = globalThis.fetch;
+
+  afterEach(() => {
+    globalThis.fetch = originalFetch;
+    vi.restoreAllMocks();
+  });
+
+  it("maps Azure voice metadata into speech voice options", async () => {
+    globalThis.fetch = vi.fn().mockResolvedValue(
+      new Response(
+        JSON.stringify([
+          {
+            Name: "Microsoft Server Speech Text to Speech Voice (zh-HK, HiuMaanNeural)",
+            DisplayName: "HiuMaan Neural (zh-HK)",
+            LocalName: "HiuMaan",
+            ShortName: "zh-HK-HiuMaanNeural",
+            Gender: "Female",
+            Locale: "zh-HK",
+            VoiceType: "Neural",
+            Status: "Available",
+          },
+          {
+            Name: "Microsoft Server Speech Text to Speech Voice (zh-CN, XiaoxiaoNeural)",
+            DisplayName: "Xiaoxiao Neural (zh-CN)",
+            ShortName: "zh-CN-XiaoxiaoNeural",
+            Gender: "Female",
+            Locale: "zh-CN",
+            VoiceType: "Neural",
+            Status: "Available",
+          },
+        ]),
+        { status: 200 },
+      ),
+    ) as typeof globalThis.fetch;
+
+    const voices = await listAzureVoices({
+      apiKey: "test-key",
+      region: "eastus",
+    });
+
+    expect(voices).toEqual([
+      {
+        id: "zh-HK-HiuMaanNeural",
+        name: "HiuMaan Neural (zh-HK)",
+        category: "Neural",
+        locale: "zh-HK",
+        gender: "Female",
+      },
+      {
+        id: "zh-CN-XiaoxiaoNeural",
+        name: "Xiaoxiao Neural (zh-CN)",
+        category: "Neural",
+        locale: "zh-CN",
+        gender: "Female",
+      },
+    ]);
+    expect(globalThis.fetch).toHaveBeenCalledWith(
+      "https://eastus.tts.speech.microsoft.com/cognitiveservices/voices/list",
+      expect.objectContaining({
+        headers: expect.objectContaining({
+          "Ocp-Apim-Subscription-Key": "test-key",
+        }),
+      }),
+    );
+  });
+
+  it("filters out deprecated voices", async () => {
+    globalThis.fetch = vi.fn().mockResolvedValue(
+      new Response(
+        JSON.stringify([
+          {
+            ShortName: "zh-HK-HiuMaanNeural",
+            Gender: "Female",
+            Locale: "zh-HK",
+            Status: "Available",
+          },
+          {
+            ShortName: "zh-HK-OldVoice",
+            Gender: "Male",
+            Locale: "zh-HK",
+            Status: "Deprecated",
+          },
+        ]),
+        { status: 200 },
+      ),
+    ) as typeof globalThis.fetch;
+
+    const voices = await listAzureVoices({
+      apiKey: "test-key",
+    });
+
+    expect(voices).toHaveLength(1);
+    expect(voices[0].id).toBe("zh-HK-HiuMaanNeural");
+  });
+
+  it("throws on Azure voice list failures", async () => {
+    globalThis.fetch = vi
+      .fn()
+      .mockResolvedValue(new Response("nope", { status: 503 })) as typeof globalThis.fetch;
+
+    await expect(
+      listAzureVoices({ apiKey: "test-key", region: "eastus" }),
+    ).rejects.toThrow("Azure voices API error (503)");
+  });
+
+  it("uses custom baseUrl when provided", async () => {
+    globalThis.fetch = vi.fn().mockResolvedValue(
+      new Response(JSON.stringify([]), { status: 200 }),
+    ) as typeof globalThis.fetch;
+
+    await listAzureVoices({
+      apiKey: "test-key",
+      baseUrl: "https://custom.region.tts.speech.microsoft.com",
+    });
+
+    expect(globalThis.fetch).toHaveBeenCalledWith(
+      "https://custom.region.tts.speech.microsoft.com/cognitiveservices/voices/list",
+      expect.any(Object),
+    );
+  });
+});