将LLM深度集成到CI/CD：自动化代码审查与测试生成

name: AI Code Review

on:
  pull_request:
    types: [opened, synchronize] # 当 PR 被创建或更新时触发

jobs:
  review:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@v4
        with:
          fetch-depth: 0 # 获取完整的 git 历史，以便生成精确的 diff

      - name: Setup Node.js
        uses: actions/setup-node@v4
        with:
          node-version: '20'

      - name: Install dependencies
        run: npm install axios @actions/github @actions/core

      - name: Run AI Review Script
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          OPENAI_API_KEY: ${{ secrets.OPENAI_API_KEY }}
        run: node scripts/ai-reviewer.js

const github = require('@actions/github');
const core = require('@actions/core');
const axios = require('axios');

async function run() {
  try {
    const token = process.env.GITHUB_TOKEN;
    const openaiKey = process.env.OPENAI_API_KEY;
    const octokit = github.getOctokit(token);
    const context = github.context;

    if (context.eventName !== 'pull_request') return;

    const prNumber = context.payload.pull_request.number;
    const owner = context.repo.owner;
    const repo = context.repo.repo;

    // 1. 获取 PR 的所有文件变更 (Diff)
    const { data: files } = await octokit.rest.pulls.listFiles({
      owner,
      repo,
      pull_number: prNumber,
    });

    for (const file of files) {
      // 忽略锁文件、图片或过大的变更
      if (file.filename.endsWith('.lock') || file.changes > 500) continue;

      const diffContent = file.patch;
      if (!diffContent) continue;

      // 2. 构建 Prompt，要求 LLM 进行审查
      const prompt = `
你是一个资深的软件架构师。请审查以下代码变更（Git Diff 格式），指出潜在的 Bug、性能问题或安全隐患。
如果代码没有明显问题，请回复 "LGTM"。否则，请提供具体的修改建议。

文件名: ${file.filename}
变更内容:
\`\`\`diff
${diffContent}
\`\`\`
      `;

      // 3. 调用 OpenAI API
      const response = await axios.post(
        'https://api.openai.com/v1/chat/completions',
        {
          model: 'gpt-4-turbo-preview',
          messages: [{ role: 'user', content: prompt }],
          temperature: 0.2,
        },
        {
          headers: {
            'Authorization': `Bearer ${openaiKey}`,
            'Content-Type': 'application/json',
          },
        }
      );

      const reviewComment = response.data.choices[0].message.content;

      // 4. 将审查意见作为 PR 评论发布
      if (reviewComment && reviewComment.trim() !== "LGTM") {
        await octokit.rest.pulls.createReviewComment({
          owner,
          repo,
          pull_number: prNumber,
          body: `🤖 **AI Reviewer**:\n\n${reviewComment}`,
          commit_id: context.payload.pull_request.head.sha,
          path: file.filename,
          position: 1, // 简化示例，实际应根据 diff 计算具体的行号
        });
      }
    }
  } catch (error) {
    core.setFailed(error.message);
  }
}

run();

作为 QA 工程师，请为以下新增的函数编写完整的单元测试（使用 Jest 框架）。
要求：
1. 必须覆盖所有边界条件（如空输入、极大值）。
2. 必须模拟（Mock）外部依赖。
3. 请只输出测试代码本身。

[新增函数代码]