2 files changed, 187 insertions, 5 deletions
diff --git a/packages/cli/src/utils/gitUtils.test.ts b/packages/cli/src/utils/gitUtils.test.ts
new file mode 100644
index 00000000..4a29f589
--- /dev/null
+++ b/packages/cli/src/utils/gitUtils.test.ts
@@ -0,0 +1,115 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { vi, describe, expect, it, afterEach, beforeEach } from 'vitest';
+import * as child_process from 'child_process';
+import {
+  isGitHubRepository,
+  getGitRepoRoot,
+  getLatestGitHubRelease,
+} from './gitUtils.js';
+
+vi.mock('child_process');
+
+describe('isGitHubRepository', async () => {
+  beforeEach(() => {
+    vi.resetAllMocks();
+  });
+
+  afterEach(() => {
+    vi.restoreAllMocks();
+  });
+
+  it('returns false if the git command fails', async () => {
+    vi.mocked(child_process.execSync).mockImplementation((): string => {
+      throw new Error('oops');
+    });
+    expect(isGitHubRepository()).toBe(false);
+  });
+
+  it('returns false if the remote is not github.com', async () => {
+    vi.mocked(child_process.execSync).mockReturnValueOnce('https://gitlab.com');
+    expect(isGitHubRepository()).toBe(false);
+  });
+
+  it('returns true if the remote is github.com', async () => {
+    vi.mocked(child_process.execSync).mockReturnValueOnce(`
+      origin  https://github.com/sethvargo/gemini-cli (fetch)
+      origin  https://github.com/sethvargo/gemini-cli (push)
+    `);
+    expect(isGitHubRepository()).toBe(true);
+  });
+});
+
+describe('getGitRepoRoot', async () => {
+  beforeEach(() => {
+    vi.resetAllMocks();
+  });
+
+  afterEach(() => {
+    vi.restoreAllMocks();
+  });
+
+  it('throws an error if git root cannot be determined', async () => {
+    vi.mocked(child_process.execSync).mockImplementation((): string => {
+      throw new Error('oops');
+    });
+    expect(() => {
+      getGitRepoRoot();
+    }).toThrowError(/oops/);
+  });
+
+  it('throws an error if git root is empty', async () => {
+    vi.mocked(child_process.execSync).mockReturnValueOnce('');
+    expect(() => {
+      getGitRepoRoot();
+    }).toThrowError(/Git repo returned empty value/);
+  });
+
+  it('returns the root', async () => {
+    vi.mocked(child_process.execSync).mockReturnValueOnce('/path/to/git/repo');
+    expect(getGitRepoRoot()).toBe('/path/to/git/repo');
+  });
+});
+
+describe('getLatestRelease', async () => {
+  beforeEach(() => {
+    vi.resetAllMocks();
+  });
+
+  afterEach(() => {
+    vi.restoreAllMocks();
+  });
+
+  it('throws an error if the fetch fails', async () => {
+    global.fetch = vi.fn(() => Promise.reject('nope'));
+    expect(getLatestGitHubRelease()).rejects.toThrowError(
+      /Unable to determine the latest/,
+    );
+  });
+
+  it('throws an error if the fetch does not return a json body', async () => {
+    global.fetch = vi.fn(() =>
+      Promise.resolve({
+        ok: true,
+        json: () => Promise.resolve({ foo: 'bar' }),
+      } as Response),
+    );
+    expect(getLatestGitHubRelease()).rejects.toThrowError(
+      /Unable to determine the latest/,
+    );
+  });
+
+  it('returns the release version', async () => {
+    global.fetch = vi.fn(() =>
+      Promise.resolve({
+        ok: true,
+        json: () => Promise.resolve({ tag_name: 'v1.2.3' }),
+      } as Response),
+    );
+    expect(getLatestGitHubRelease()).resolves.toBe('v1.2.3');
+  });
+});
diff --git a/packages/cli/src/utils/gitUtils.ts b/packages/cli/src/utils/gitUtils.ts
index d510008c..30ca2245 100644
--- a/packages/cli/src/utils/gitUtils.ts
+++ b/packages/cli/src/utils/gitUtils.ts
@@ -5,22 +5,89 @@
  */
 
 import { execSync } from 'child_process';
+import { ProxyAgent, setGlobalDispatcher } from 'undici';
 
 /**
  * Checks if a directory is within a git repository hosted on GitHub.
  * @returns true if the directory is in a git repository with a github.com remote, false otherwise
  */
-export function isGitHubRepository(): boolean {
+export const isGitHubRepository = (): boolean => {
   try {
-    const remotes = execSync('git remote -v', {
-      encoding: 'utf-8',
-    });
+    const remotes = (
+      execSync('git remote -v', {
+        encoding: 'utf-8',
+      }) || ''
+    ).trim();
 
     const pattern = /github\.com/;
 
     return pattern.test(remotes);
   } catch (_error) {
     // If any filesystem error occurs, assume not a git repo
+    console.debug(`Failed to get git remote:`, _error);
     return false;
   }
-}
+};
+
+/**
+ * getGitRepoRoot returns the root directory of the git repository.
+ * @returns the path to the root of the git repo.
+ * @throws error if the exec command fails.
+ */
+export const getGitRepoRoot = (): string => {
+  const gitRepoRoot = (
+    execSync('git rev-parse --show-toplevel', {
+      encoding: 'utf-8',
+    }) || ''
+  ).trim();
+
+  if (!gitRepoRoot) {
+    throw new Error(`Git repo returned empty value`);
+  }
+
+  return gitRepoRoot;
+};
+
+/**
+ * getLatestGitHubRelease returns the release tag as a string.
+ * @returns string of the release tag (e.g. "v1.2.3").
+ */
+export const getLatestGitHubRelease = async (
+  proxy?: string,
+): Promise<string> => {
+  try {
+    const controller = new AbortController();
+    if (proxy) {
+      setGlobalDispatcher(new ProxyAgent(proxy));
+    }
+
+    const endpoint = `https://api.github.com/repos/google-github-actions/run-gemini-cli/releases/latest`;
+
+    const response = await fetch(endpoint, {
+      method: 'GET',
+      headers: {
+        Accept: 'application/vnd.github+json',
+        'Content-Type': 'application/json',
+        'X-GitHub-Api-Version': '2022-11-28',
+      },
+      signal: controller.signal,
+    });
+
+    if (!response.ok) {
+      throw new Error(
+        `Invalid response code: ${response.status} - ${response.statusText}`,
+      );
+    }
+
+    const releaseTag = (await response.json()).tag_name;
+    if (!releaseTag) {
+      throw new Error(`Response did not include tag_name field`);
+    }
+    return releaseTag;
+  } catch (_error) {
+    console.debug(`Failed to determine latest run-gemini-cli release:`, _error);
+    throw new Error(
+      `Unable to determine the latest run-gemini-cli release on GitHub.`,
+    );
+  }
+};