feat: add jam review command

src/commands/review.test.ts

@@ -0,0 +1,317 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
+import type { MockInstance } from 'vitest';
+
+// ── Module mocks ──────────────────────────────────────────────────────────────
+
+vi.mock('node:child_process', () => ({
+  execFile: vi.fn(),
+}));
+
+vi.mock('../utils/workspace.js', () => ({
+  getWorkspaceRoot: vi.fn(),
+}));
+
+vi.mock('../config/loader.js', () => ({
+  loadConfig: vi.fn(),
+  getActiveProfile: vi.fn(),
+}));
+
+vi.mock('../providers/factory.js', () => ({
+  createProvider: vi.fn(),
+}));
+
+vi.mock('../utils/stream.js', () => ({
+  withRetry: vi.fn((fn: () => unknown) => fn()),
+  collectStream: vi.fn(),
+}));
+
+vi.mock('../ui/renderer.js', () => ({
+  streamToStdout: vi.fn(),
+  printJsonResult: vi.fn(),
+  printError: vi.fn(),
+}));
+
+// ── Imports after mocks ───────────────────────────────────────────────────────
+
+import { execFile } from 'node:child_process';
+import { getWorkspaceRoot } from '../utils/workspace.js';
+import { loadConfig, getActiveProfile } from '../config/loader.js';
+import { createProvider } from '../providers/factory.js';
+import { collectStream } from '../utils/stream.js';
+import { streamToStdout, printJsonResult, printError } from '../ui/renderer.js';
+import {
+  buildReviewPrompt,
+  getBranchDiff,
+  getMergeBase,
+  getPrDiff,
+  getCurrentBranch,
+  runReview,
+} from './review.js';
+
+const execFileMock = execFile as unknown as ReturnType<typeof vi.fn>;
+
+// ── Helpers ───────────────────────────────────────────────────────────────────
+
+const FAKE_DIFF = `diff --git a/src/foo.ts b/src/foo.ts\n+export const x = 1;`;
+const FAKE_MERGE_BASE = 'abc1234';
+
+/**
+ * Stubs execFile with a callback-style mock compatible with promisify.
+ */
+function mockExecSequence(
+  responses: Array<{ match: string | ((args: string[]) => boolean); result: { stdout: string } | Error }>
+) {
+  execFileMock.mockImplementation(
+    (
+      _cmd: string,
+      args: string[],
+      _opts: unknown,
+      cb: (err: Error | null, res?: { stdout: string }) => void
+    ) => {
+      const entry = responses.find((r) =>
+        typeof r.match === 'function' ? r.match(args) : args.includes(r.match)
+      );
+      if (!entry) {
+        cb(null, { stdout: '' });
+        return;
+      }
+      if (entry.result instanceof Error) {
+        cb(entry.result);
+      } else {
+        cb(null, entry.result);
+      }
+    }
+  );
+}
+
+function setupHappyPath() {
+  (getWorkspaceRoot as ReturnType<typeof vi.fn>).mockResolvedValue('/repo');
+  (loadConfig as ReturnType<typeof vi.fn>).mockResolvedValue({});
+  (getActiveProfile as ReturnType<typeof vi.fn>).mockReturnValue({
+    model: 'gpt-4o',
+    temperature: 0.2,
+    maxTokens: 1024,
+    systemPrompt: undefined,
+  });
+  (createProvider as ReturnType<typeof vi.fn>).mockResolvedValue({
+    streamCompletion: vi.fn(),
+  });
+  (streamToStdout as ReturnType<typeof vi.fn>).mockResolvedValue(undefined);
+  (collectStream as ReturnType<typeof vi.fn>).mockResolvedValue({
+    text: 'Review result',
+    usage: { promptTokens: 10, completionTokens: 20 },
+  });
+
+  mockExecSequence([
+    { match: 'merge-base', result: { stdout: FAKE_MERGE_BASE } },
+    { match: '--abbrev-ref', result: { stdout: 'feature/my-branch' } },
+    {
+      match: (args) => args.includes(FAKE_MERGE_BASE) && args.includes('HEAD'),
+      result: { stdout: FAKE_DIFF },
+    },
+  ]);
+}
+
+// ── buildReviewPrompt ─────────────────────────────────────────────────────────
+
+describe('buildReviewPrompt', () => {
+  it('includes the diff in a fenced code block', () => {
+    const prompt = buildReviewPrompt('diff content', 'context info');
+    expect(prompt).toContain('```diff\ndiff content\n```');
+  });
+
+  it('includes the context string', () => {
+    const prompt = buildReviewPrompt('diff content', 'Reviewing branch "feat" vs "main".');
+    expect(prompt).toContain('Reviewing branch "feat" vs "main".');
+  });
+
+  it('asks for summary, issues, and suggestions', () => {
+    const prompt = buildReviewPrompt('', '');
+    expect(prompt).toContain('Summary');
+    expect(prompt).toContain('Potential Issues');
+    expect(prompt).toContain('Suggestions');
+  });
+});
+
+// ── getMergeBase ──────────────────────────────────────────────────────────────
+
+describe('getMergeBase', () => {
+  it('returns the merge-base SHA', async () => {
+    execFileMock.mockImplementation(
+      (_cmd: string, _args: string[], _opts: unknown, cb: (err: null, res: { stdout: string }) => void) => {
+        cb(null, { stdout: '  abc1234  \n' });
+      }
+    );
+    const result = await getMergeBase('/repo', 'main');
+    expect(result).toBe('abc1234');
+  });
+
+  it('throws JamError when git fails', async () => {
+    execFileMock.mockImplementation(
+      (_cmd: string, _args: string[], _opts: unknown, cb: (err: Error) => void) => {
+        cb(new Error('not a git repo'));
+      }
+    );
+    await expect(getMergeBase('/repo', 'main')).rejects.toThrow('merge-base');
+  });
+});
+
+// ── getBranchDiff ─────────────────────────────────────────────────────────────
+
+describe('getBranchDiff', () => {
+  it('returns trimmed diff output', async () => {
+    mockExecSequence([
+      { match: 'merge-base', result: { stdout: FAKE_MERGE_BASE } },
+      {
+        match: (args) => args.includes(FAKE_MERGE_BASE) && args.includes('HEAD'),
+        result: { stdout: `  ${FAKE_DIFF}  ` },
+      },
+    ]);
+    const result = await getBranchDiff('/repo', 'main');
+    expect(result).toBe(FAKE_DIFF);
+  });
+
+  it('throws JamError when git diff fails', async () => {
+    mockExecSequence([
+      { match: 'merge-base', result: { stdout: FAKE_MERGE_BASE } },
+      {
+        match: (args) => args.includes(FAKE_MERGE_BASE),
+        result: new Error('git exploded'),
+      },
+    ]);
+    await expect(getBranchDiff('/repo', 'main')).rejects.toThrow('diff against');
+  });
+});
+
+// ── getPrDiff ─────────────────────────────────────────────────────────────────
+
+describe('getPrDiff', () => {
+  it('returns the PR diff from gh CLI', async () => {
+    execFileMock.mockImplementation(
+      (_cmd: string, _args: string[], _opts: unknown, cb: (err: null, res: { stdout: string }) => void) => {
+        cb(null, { stdout: FAKE_DIFF });
+      }
+    );
+    const result = await getPrDiff('/repo', 42);
+    expect(result).toBe(FAKE_DIFF);
+  });
+
+  it('throws JamError mentioning gh CLI when it fails', async () => {
+    execFileMock.mockImplementation(
+      (_cmd: string, _args: string[], _opts: unknown, cb: (err: Error) => void) => {
+        cb(new Error('gh not found'));
+      }
+    );
+    await expect(getPrDiff('/repo', 42)).rejects.toThrow('GitHub CLI');
+  });
+});
+
+// ── getCurrentBranch ──────────────────────────────────────────────────────────
+
+describe('getCurrentBranch', () => {
+  it('returns the current branch name', async () => {
+    execFileMock.mockImplementation(
+      (_cmd: string, _args: string[], _opts: unknown, cb: (err: null, res: { stdout: string }) => void) => {
+        cb(null, { stdout: 'feature/my-branch\n' });
+      }
+    );
+    const result = await getCurrentBranch('/repo');
+    expect(result).toBe('feature/my-branch');
+  });
+});
+
+// ── runReview ─────────────────────────────────────────────────────────────────
+
+describe('runReview', () => {
+  let processExitSpy: MockInstance<[code?: string | number | null | undefined], never>;
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    processExitSpy = vi
+      .spyOn(process, 'exit')
+      .mockImplementation((_code) => { throw new Error('process.exit'); }) as typeof processExitSpy;
+  });
+
+  afterEach(() => {
+    processExitSpy.mockRestore();
+  });
+
+  it('streams a branch review to stdout', async () => {
+    setupHappyPath();
+    await runReview({ base: 'main' });
+    expect(streamToStdout).toHaveBeenCalledOnce();
+    expect(printError).not.toHaveBeenCalled();
+  });
+
+  it('uses "main" as the default base', async () => {
+    setupHappyPath();
+    await runReview({});
+    // merge-base should have been called with 'main'
+    const calls = execFileMock.mock.calls as Array<[string, string[], unknown, unknown]>;
+    const mergeBaseCall = calls.find(([, args]) => args.includes('merge-base'));
+    expect(mergeBaseCall).toBeDefined();
+    expect(mergeBaseCall![1]).toContain('main');
+  });
+
+  it('outputs JSON when --json is set', async () => {
+    setupHappyPath();
+    await runReview({ base: 'main', json: true });
+    expect(printJsonResult).toHaveBeenCalledOnce();
+    expect(streamToStdout).not.toHaveBeenCalled();
+  });
+
+  it('prints nothing to review when the diff is empty', async () => {
+    (getWorkspaceRoot as ReturnType<typeof vi.fn>).mockResolvedValue('/repo');
+    mockExecSequence([
+      { match: 'merge-base', result: { stdout: FAKE_MERGE_BASE } },
+      { match: '--abbrev-ref', result: { stdout: 'feature/x' } },
+      {
+        match: (args) => args.includes(FAKE_MERGE_BASE) && args.includes('HEAD'),
+        result: { stdout: '' },
+      },
+    ]);
+
+    const writeSpy = vi.spyOn(process.stdout, 'write').mockImplementation(() => true);
+    await runReview({ base: 'main' });
+    expect(writeSpy).toHaveBeenCalledWith(expect.stringContaining('No differences'));
+    expect(streamToStdout).not.toHaveBeenCalled();
+    writeSpy.mockRestore();
+  });
+
+  it('uses gh pr diff when --pr is provided', async () => {
+    (getWorkspaceRoot as ReturnType<typeof vi.fn>).mockResolvedValue('/repo');
+    (loadConfig as ReturnType<typeof vi.fn>).mockResolvedValue({});
+    (getActiveProfile as ReturnType<typeof vi.fn>).mockReturnValue({
+      model: 'gpt-4o',
+      temperature: 0.2,
+      maxTokens: 1024,
+      systemPrompt: undefined,
+    });
+    (createProvider as ReturnType<typeof vi.fn>).mockResolvedValue({ streamCompletion: vi.fn() });
+    (streamToStdout as ReturnType<typeof vi.fn>).mockResolvedValue(undefined);
+
+    execFileMock.mockImplementation(
+      (_cmd: string, args: string[], _opts: unknown, cb: (err: null, res: { stdout: string }) => void) => {
+        if (args.includes('diff') && args.includes('42')) {
+          cb(null, { stdout: FAKE_DIFF });
+        } else {
+          cb(null, { stdout: '' });
+        }
+      }
+    );
+
+    await runReview({ pr: 42 });
+    expect(streamToStdout).toHaveBeenCalledOnce();
+    const calls = execFileMock.mock.calls as Array<[string, string[], unknown, unknown]>;
+    const ghCall = calls.find(([cmd]) => cmd === 'gh');
+    expect(ghCall).toBeDefined();
+    expect(ghCall![1]).toContain('42');
+  });
+
+  it('exits with code 1 and prints error on failure', async () => {
+    (getWorkspaceRoot as ReturnType<typeof vi.fn>).mockRejectedValue(new Error('no workspace'));
+    await expect(runReview({})).rejects.toThrow('process.exit');
+    expect(printError).toHaveBeenCalled();
+    expect(processExitSpy).toHaveBeenCalledWith(1);
+  });
+});