Slack: add send blocks behavior tests

src/slack/send.blocks.test.ts

@@ -0,0 +1,65 @@
+import type { WebClient } from "@slack/web-api";
+import { describe, expect, it, vi } from "vitest";
+
+vi.mock("../config/config.js", () => ({
+  loadConfig: () => ({}),
+}));
+
+vi.mock("./accounts.js", () => ({
+  resolveSlackAccount: () => ({
+    accountId: "default",
+    botToken: "xoxb-test",
+    botTokenSource: "config",
+    config: {},
+  }),
+}));
+
+const { sendMessageSlack } = await import("./send.js");
+
+function createClient() {
+  return {
+    conversations: {
+      open: vi.fn(async () => ({ channel: { id: "D123" } })),
+    },
+    chat: {
+      postMessage: vi.fn(async () => ({ ts: "171234.567" })),
+    },
+  } as unknown as WebClient & {
+    conversations: { open: ReturnType<typeof vi.fn> };
+    chat: { postMessage: ReturnType<typeof vi.fn> };
+  };
+}
+
+describe("sendMessageSlack blocks", () => {
+  it("posts blocks with fallback text when message is empty", async () => {
+    const client = createClient();
+    const result = await sendMessageSlack("channel:C123", "", {
+      token: "xoxb-test",
+      client,
+      blocks: [{ type: "divider" }],
+    });
+
+    expect(client.conversations.open).not.toHaveBeenCalled();
+    expect(client.chat.postMessage).toHaveBeenCalledWith(
+      expect.objectContaining({
+        channel: "C123",
+        text: " ",
+        blocks: [{ type: "divider" }],
+      }),
+    );
+    expect(result).toEqual({ messageId: "171234.567", channelId: "C123" });
+  });
+
+  it("rejects blocks combined with mediaUrl", async () => {
+    const client = createClient();
+    await expect(
+      sendMessageSlack("channel:C123", "hi", {
+        token: "xoxb-test",
+        client,
+        mediaUrl: "https://example.com/image.png",
+        blocks: [{ type: "divider" }],
+      }),
+    ).rejects.toThrow(/does not support blocks with mediaUrl/i);
+    expect(client.chat.postMessage).not.toHaveBeenCalled();
+  });
+});