famapp/tests/unit/agent-chat.test.ts

import assert from "node:assert/strict";
import { describe, it } from "node:test";
import { createMockLlmClient } from "../../src/lib/llm/mock";
import { getLlmConfig } from "../../src/lib/llm/config";
import { runAgentChat } from "../../src/modules/agent/server/run";

describe("mock llm provider", () => {
  it("returns a plain assistant message by default", async () => {
    const client = createMockLlmClient();
    const result = await client.chatCompletion({
      messages: [{ role: "user", content: "hello" }],
      tools: [],
    });
    assert.equal(result.message.role, "assistant");
    assert.ok(result.message.content?.includes("mock provider"));
  });

  it("requests add_list_item when the user mentions milk", async () => {
    const client = createMockLlmClient();
    const result = await client.chatCompletion({
      messages: [{ role: "user", content: "add milk to shopping list" }],
      tools: [
        {
          type: "function",
          function: {
            name: "add_list_item",
            description: "add",
            parameters: { type: "object", properties: {} },
          },
        },
      ],
    });
    assert.equal(result.message.tool_calls?.[0]?.function.name, "add_list_item");
  });
});

describe("getLlmConfig", () => {
  it("uses mock provider when base url is unset", () => {
    const original = process.env.LLM_BASE_URL;
    const originalProvider = process.env.LLM_PROVIDER;
    delete process.env.LLM_BASE_URL;
    delete process.env.LLM_PROVIDER;

    const config = getLlmConfig();
    assert.equal(config.provider, "mock");

    if (original === undefined) delete process.env.LLM_BASE_URL;
    else process.env.LLM_BASE_URL = original;
    if (originalProvider === undefined) delete process.env.LLM_PROVIDER;
    else process.env.LLM_PROVIDER = originalProvider;
  });
});

describe("runAgentChat", () => {
  it("executes tool calls and returns a final assistant message", async () => {
    const executed: string[] = [];
    const result = await runAgentChat({
      messages: [{ role: "user", content: "add milk to the shopping list" }],
      request: new Request("http://localhost:3000/api/agent/chat"),
      llm: createMockLlmClient(),
      executeTool: async (name) => {
        executed.push(name);
        return JSON.stringify({ status: 201, body: { id: "item-1", text: "milk" } });
      },
    });

    assert.deepEqual(executed, ["add_list_item"]);
    assert.equal(result.message.role, "assistant");
    assert.ok(result.message.content.length > 0);
    assert.equal(result.toolCalls.length, 1);
    assert.equal(result.toolCalls[0]?.name, "add_list_item");
    assert.equal(result.toolCalls[0]?.status, 201);
  });

  it("accepts a custom system prompt override", async () => {
    const result = await runAgentChat({
      messages: [{ role: "user", content: "hello" }],
      request: new Request("http://localhost:3000/api/agent/chat"),
      systemPrompt: "You are a pirate.",
      llm: createMockLlmClient(),
    });

    assert.equal(result.message.role, "assistant");
    assert.ok(result.message.content.length > 0);
  });
});