Merge 14150cf66c into 0c366fd6a8

This PR fixes several issues with tag handling in the checkout action:

1. fetch-tags: true now works (fixes #1471)
   - Tags refspec is now included in getRefSpec() when fetchTags=true
   - Previously tags were only fetched during a separate fetch that was
     overwritten by the main fetch

2. Tag checkout preserves annotations (fixes #290)
   - Tags are fetched via refspec (+refs/tags/*:refs/tags/*) instead of
     --tags flag
   - This fetches the actual tag objects, preserving annotations

3. Tag checkout with fetch-tags: true no longer fails (fixes #1467)
   - When checking out a tag with fetchTags=true, only the wildcard
     refspec is used (specific tag refspec is redundant)

Changes:
- src/ref-helper.ts: getRefSpec() now accepts fetchTags parameter and
  prepends tags refspec when true
- src/git-command-manager.ts: fetch() simplified to always use --no-tags,
  tags are fetched explicitly via refspec
- src/git-source-provider.ts: passes fetchTags to getRefSpec()
- Added E2E test for fetch-tags option

Related #1471, #1467, #290

.github/copilot-instructions.md

@@ -0,0 +1,121 @@
+# GitHub Actions Checkout - AI Coding Instructions
+
+## Project Overview
+
+This is the official `actions/checkout` GitHub Action for checking out repositories in workflows. It's a TypeScript project that compiles to a single bundled JavaScript file (`dist/index.js`) and supports both git-based and REST API-based repository downloads.
+
+## Architecture & Key Components
+
+### Core Entry Points
+- **`src/main.ts`**: Main entry point with `run()` and `cleanup()` functions, determined by `stateHelper.IsPost`
+- **`src/git-source-provider.ts`**: Primary orchestrator for repository acquisition (git vs REST API fallback)
+- **`src/input-helper.ts`**: Input validation and GitHub Actions input processing
+- **`action.yml`**: Defines the action interface with comprehensive input/output schema
+
+### Critical Data Flow
+1. `main.ts` → `inputHelper.getInputs()` → validates and transforms action inputs
+2. `main.ts` → `gitSourceProvider.getSource(settings)` → orchestrates repository download
+3. `git-source-provider.ts` decides: use Git CLI or fallback to GitHub REST API
+4. State management via `state-helper.ts` for POST action cleanup
+
+### Authentication & Security Patterns
+- **Token-based auth**: Uses `@actions/core` to handle GitHub tokens securely
+- **SSH key management**: Configures temporary SSH keys in `git-auth-helper.ts`
+- **Safe directory**: Automatically configures `git config safe.directory` for container compatibility
+
+## Development Workflow
+
+### Essential Commands
+```bash
+npm ci                    # Install dependencies
+npm run build            # TypeScript → JavaScript + bundle with ncc + generate docs
+npm run format           # Prettier formatting
+npm run lint            # ESLint validation
+npm test                # Jest test suite
+```
+
+### Build Process (Critical!)
+- **`npm run build`** runs: `tsc && ncc build && node lib/misc/generate-docs.js`
+- **Documentation sync**: `src/misc/generate-docs.ts` auto-updates README.md usage section from `action.yml`
+- **Bundling**: Uses `@vercel/ncc` to create single `dist/index.js` file
+- **Always run `npm run build` before commits** - the `dist/` directory must be up-to-date
+
+### Testing Strategy
+- **Unit tests**: Jest tests in `__test__/` for all core modules
+- **Integration tests**: Shell scripts (`__test__/verify-*.sh`) test real git operations
+- **E2E tests**: `.github/workflows/test.yml` tests across OS matrix with actual GitHub repos
+
+## Project-Specific Conventions
+
+### TypeScript Patterns
+- **Interface-driven**: `IGitSourceSettings` centralizes all configuration
+- **Async/await**: All I/O operations use async patterns, not promises
+- **Error handling**: Use `core.setFailed()` for action failures, `core.warning()` for non-critical issues
+
+### Git Operation Patterns
+```typescript
+// Check Git version and fallback pattern
+const git = await getGitCommandManager(settings)
+if (git) {
+  // Use Git CLI
+  await git.fetch(refSpec, fetchDepth)
+} else {
+  // Fallback to REST API
+  await githubApiHelper.downloadRepository(...)
+}
+```
+
+### State Management (Unique Pattern!)
+- **Dual-phase execution**: Same script runs twice (MAIN + POST) determined by `stateHelper.IsPost`
+- **State persistence**: Use `core.saveState()` / `core.getState()` to pass data between phases
+- **Cleanup responsibility**: POST phase cleans up auth tokens, SSH keys, etc.
+
+### Input Validation Approach
+- **GitHub context integration**: Defaults repository from `github.context.repo`
+- **Path safety**: Validates paths are within `GITHUB_WORKSPACE`
+- **Flexible refs**: Handles branches, tags, SHAs, and PR refs uniformly
+
+## Integration Points
+
+### GitHub Actions SDK Usage
+- **`@actions/core`**: Input/output, logging, state management
+- **`@actions/github`**: GitHub context and API access
+- **`@actions/exec`**: Git command execution
+- **`@actions/io`**: File system operations
+
+### Git Integration
+- **Version compatibility**: Minimum Git 2.18, with feature detection for sparse-checkout
+- **Authentication modes**: Token-based (default) or SSH key-based
+- **Advanced features**: LFS, submodules, sparse-checkout, partial clones
+
+### Container Support
+- **Safe directory**: Critical for container workflows - auto-configures git safe.directory
+- **Credential persistence**: Configures git credential helper for authenticated operations
+
+## Common Debugging Patterns
+
+### Enable Debug Logging
+```yaml
+steps:
+  - uses: actions/checkout@v5
+    env:
+      ACTIONS_STEP_DEBUG: true
+```
+
+### REST API Fallback Testing
+```bash
+# Force REST API mode by overriding Git version
+__test__/override-git-version.sh
+```
+
+### Authentication Issues
+- Check `GITHUB_TOKEN` permissions: needs `contents: read`
+- For private repos: requires PAT with repo access
+- Container issues: verify safe.directory configuration
+
+## Key Files for Understanding
+- `src/git-source-provider.ts` - Main orchestration logic
+- `src/input-helper.ts` - Action interface and validation
+- `src/git-auth-helper.ts` - Authentication and credential management
+- `action.yml` - Complete input/output specification
+- `.github/workflows/test.yml` - Comprehensive test scenarios

.github/workflows/check-dist.yml

@@ -22,7 +22,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v6
 
       - name: Set Node.js 24.x
         uses: actions/setup-node@v4

.github/workflows/codeql-analysis.yml

@@ -39,7 +39,7 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v4.1.6
+      uses: actions/checkout@v6
 
     - name: Initialize CodeQL
       uses: github/codeql-action/init@v3

.github/workflows/deno.yml

@@ -0,0 +1,41 @@
+# This workflow uses actions that are not certified by GitHub.
+# They are provided by a third-party and are governed by
+# separate terms of service, privacy policy, and support
+# documentation.
+
+# This workflow will install Deno then run `deno lint` and `deno test`.
+# For more information see: https://github.com/denoland/setup-deno
+
+name: Deno
+
+on:
+  push:
+    branches: ["main"]
+  pull_request:
+    branches: ["main"]
+
+permissions:
+  contents: read
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Setup repo
+        uses: actions/checkout@v4
+
+      - name: Setup Deno
+        uses: denoland/setup-deno@v1.1.2
+        with:
+          deno-version: v1.x
+
+      # Uncomment this step to verify the use of 'deno fmt' on each commit.
+      # - name: Verify formatting
+      #   run: deno fmt --check
+
+      - name: Run linter
+        run: deno lint
+
+      - name: Run tests
+        run: deno test -A

.github/workflows/licensed.yml

@@ -9,6 +9,6 @@ jobs:
     runs-on: ubuntu-latest
     name: Check licenses
     steps:
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v6
       - run: npm ci
       - run: npm run licensed-check

.github/workflows/publish-immutable-actions.yml

@@ -14,7 +14,7 @@ jobs:
 
     steps:
       - name: Checking out
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
       - name: Publish
         id: publish
         uses: actions/publish-immutable-action@0.0.3

.github/workflows/test.yml

@@ -19,7 +19,7 @@ jobs:
       - uses: actions/setup-node@v4
         with:
           node-version: 24.x
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v6
       - run: npm ci
       - run: npm run build
       - run: npm run format-check
@@ -37,7 +37,7 @@ jobs:
     steps:
       # Clone this repo
       - name: Checkout
-        uses: actions/checkout@v4.1.6
+        uses: actions/checkout@v6
 
       # Basic checkout
       - name: Checkout basic
@@ -87,6 +87,17 @@ jobs:
       - name: Verify fetch filter
         run: __test__/verify-fetch-filter.sh
 
+      # Fetch tags
+      - name: Checkout with fetch-tags
+        uses: ./
+        with:
+          ref: test-data/v2/basic
+          path: fetch-tags-test
+          fetch-tags: true
+      - name: Verify fetch-tags
+        shell: bash
+        run: __test__/verify-fetch-tags.sh
+
       # Sparse checkout
       - name: Sparse checkout
         uses: ./
@@ -165,6 +176,22 @@ jobs:
       - name: Verify submodules recursive
         run: __test__/verify-submodules-recursive.sh
 
+      # Worktree credentials
+      - name: Checkout for worktree test
+        uses: ./
+        with:
+          path: worktree-test
+      - name: Verify worktree credentials
+        shell: bash
+        run: __test__/verify-worktree.sh worktree-test worktree-branch
+
+      # Worktree credentials in container step
+      - name: Verify worktree credentials in container step
+        if: runner.os == 'Linux'
+        uses: docker://bitnami/git:latest
+        with:
+          args: bash __test__/verify-worktree.sh worktree-test container-worktree-branch
+
       # Basic checkout using REST API
       - name: Remove basic
         if: runner.os != 'windows'
@@ -202,7 +229,7 @@ jobs:
     steps:
       # Clone this repo
       - name: Checkout
-        uses: actions/checkout@v4.1.6
+        uses: actions/checkout@v6
 
       # Basic checkout using git
       - name: Checkout basic
@@ -234,7 +261,7 @@ jobs:
     steps:
       # Clone this repo
       - name: Checkout
-        uses: actions/checkout@v4.1.6
+        uses: actions/checkout@v6
 
       # Basic checkout using git
       - name: Checkout basic
@@ -264,7 +291,7 @@ jobs:
     steps:
       # Clone this repo
       - name: Checkout
-        uses: actions/checkout@v4.1.6
+        uses: actions/checkout@v6
         with:
           path: localClone
 
@@ -291,8 +318,8 @@ jobs:
           git fetch --no-tags --depth=1 origin +refs/heads/main:refs/remotes/origin/main
 
       # needed to make checkout post cleanup succeed
-      - name: Fix Checkout v4
-        uses: actions/checkout@v4.1.6
+      - name: Fix Checkout v6
+        uses: actions/checkout@v6
         with:
           path: localClone
 
@@ -301,7 +328,7 @@ jobs:
     steps:
       # Clone this repo
       - name: Checkout
-        uses: actions/checkout@v4.1.6
+        uses: actions/checkout@v6
         with:
           path: actions-checkout
 

.github/workflows/update-main-version.yml

@@ -23,7 +23,7 @@ jobs:
     # Note this update workflow can also be used as a rollback tool.
     # For that reason, it's best to pin `actions/checkout` to a known, stable version
     # (typically, about two releases back).
-    - uses: actions/checkout@v4.1.6
+    - uses: actions/checkout@v6
       with:
         fetch-depth: 0
     - name: Git config

.github/workflows/update-test-ubuntu-git.yml

@@ -26,7 +26,7 @@ jobs:
  
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       # Use `docker/login-action` to log in to GHCR.io. 
       # Once published, the packages are scoped to the account defined here.

CHANGELOG.md

@@ -1,19 +1,25 @@
 # Changelog
 
-## V6.0.0
+## v6.0.2
+* Fix tag handling: preserve annotations and explicit fetch-tags by @ericsciple in https://github.com/actions/checkout/pull/2356
+
+## v6.0.1
+* Add worktree support for persist-credentials includeIf by @ericsciple in https://github.com/actions/checkout/pull/2327
+
+## v6.0.0
 * Persist creds to a separate file by @ericsciple in https://github.com/actions/checkout/pull/2286
 * Update README to include Node.js 24 support details and requirements by @salmanmkc in https://github.com/actions/checkout/pull/2248
 
-## V5.0.1
+## v5.0.1
 * Port v6 cleanup to v5 by @ericsciple in https://github.com/actions/checkout/pull/2301
 
-## V5.0.0
+## v5.0.0
 * Update actions checkout to use node 24 by @salmanmkc in https://github.com/actions/checkout/pull/2226
 
-## V4.3.1
+## v4.3.1
 * Port v6 cleanup to v4 by @ericsciple in https://github.com/actions/checkout/pull/2305
 
-## V4.3.0
+## v4.3.0
 * docs: update README.md by @motss in https://github.com/actions/checkout/pull/1971
 * Add internal repos for checking out multiple repositories by @mouismail in https://github.com/actions/checkout/pull/1977
 * Documentation update - add recommended permissions to Readme by @benwells in https://github.com/actions/checkout/pull/2043

LICENSE

@@ -1,22 +1,201 @@
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README.md

@@ -4,8 +4,9 @@
 
 ## What's new
 
-- Updated `persist-credentials` to store the credentials under `$RUNNER_TEMP` instead of directly in the local git config.
-  - This requires a minimum Actions Runner version of [v2.329.0](https://github.com/actions/runner/releases/tag/v2.329.0) to access the persisted credentials for [Docker container action](https://docs.github.com/en/actions/tutorials/use-containerized-services/create-a-docker-container-action) scenarios.
+- Improved credential security: `persist-credentials` now stores credentials in a separate file under `$RUNNER_TEMP` instead of directly in `.git/config`
+- No workflow changes required — `git fetch`, `git push`, etc. continue to work automatically
+- Running authenticated git commands from a [Docker container action](https://docs.github.com/actions/sharing-automations/creating-actions/creating-a-docker-container-action) requires Actions Runner [v2.329.0](https://github.com/actions/runner/releases/tag/v2.329.0) or later
 
 # Checkout v5
 
@@ -51,7 +52,7 @@ Please refer to the [release page](https://github.com/actions/checkout/releases/
 
 <!-- start usage -->
 ```yaml
-- uses: actions/checkout@v5
+- uses: actions/checkout@v6
   with:
     # Repository name with owner. For example, actions/checkout
     # Default: ${{ github.repository }}
@@ -190,7 +191,7 @@ Please refer to the [release page](https://github.com/actions/checkout/releases/
 ## Fetch only the root files
 
 ```yaml
-- uses: actions/checkout@v5
+- uses: actions/checkout@v6
   with:
     sparse-checkout: .
 ```
@@ -198,7 +199,7 @@ Please refer to the [release page](https://github.com/actions/checkout/releases/
 ## Fetch only the root files and `.github` and `src` folder
 
 ```yaml
-- uses: actions/checkout@v5
+- uses: actions/checkout@v6
   with:
     sparse-checkout: |
       .github
@@ -208,7 +209,7 @@ Please refer to the [release page](https://github.com/actions/checkout/releases/
 ## Fetch only a single file
 
 ```yaml
-- uses: actions/checkout@v5
+- uses: actions/checkout@v6
   with:
     sparse-checkout: |
       README.md
@@ -218,7 +219,7 @@ Please refer to the [release page](https://github.com/actions/checkout/releases/
 ## Fetch all history for all tags and branches
 
 ```yaml
-- uses: actions/checkout@v5
+- uses: actions/checkout@v6
   with:
     fetch-depth: 0
 ```
@@ -226,7 +227,7 @@ Please refer to the [release page](https://github.com/actions/checkout/releases/
 ## Checkout a different branch
 
 ```yaml
-- uses: actions/checkout@v5
+- uses: actions/checkout@v6
   with:
     ref: my-branch
 ```
@@ -234,7 +235,7 @@ Please refer to the [release page](https://github.com/actions/checkout/releases/
 ## Checkout HEAD^
 
 ```yaml
-- uses: actions/checkout@v5
+- uses: actions/checkout@v6
   with:
     fetch-depth: 2
 - run: git checkout HEAD^
@@ -244,12 +245,12 @@ Please refer to the [release page](https://github.com/actions/checkout/releases/
 
 ```yaml
 - name: Checkout
-  uses: actions/checkout@v5
+  uses: actions/checkout@v6
   with:
     path: main
 
 - name: Checkout tools repo
-  uses: actions/checkout@v5
+  uses: actions/checkout@v6
   with:
     repository: my-org/my-tools
     path: my-tools
@@ -260,10 +261,10 @@ Please refer to the [release page](https://github.com/actions/checkout/releases/
 
 ```yaml
 - name: Checkout
-  uses: actions/checkout@v5
+  uses: actions/checkout@v6
 
 - name: Checkout tools repo
-  uses: actions/checkout@v5
+  uses: actions/checkout@v6
   with:
     repository: my-org/my-tools
     path: my-tools
@@ -274,12 +275,12 @@ Please refer to the [release page](https://github.com/actions/checkout/releases/
 
 ```yaml
 - name: Checkout
-  uses: actions/checkout@v5
+  uses: actions/checkout@v6
   with:
     path: main
 
 - name: Checkout private tools
-  uses: actions/checkout@v5
+  uses: actions/checkout@v6
   with:
     repository: my-org/my-private-tools
     token: ${{ secrets.GH_PAT }} # `GH_PAT` is a secret that contains your PAT
@@ -292,7 +293,7 @@ Please refer to the [release page](https://github.com/actions/checkout/releases/
 ## Checkout pull request HEAD commit instead of merge commit
 
 ```yaml
-- uses: actions/checkout@v5
+- uses: actions/checkout@v6
   with:
     ref: ${{ github.event.pull_request.head.sha }}
 ```
@@ -308,7 +309,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
 ```
 
 ## Push a commit using the built-in token
@@ -319,7 +320,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - run: |
           date > generated.txt
           # Note: the following account information will not work on GHES
@@ -341,7 +342,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           ref: ${{ github.head_ref }}
       - run: |

__test__/git-command-manager.test.ts

@@ -108,7 +108,7 @@ describe('Test fetchDepth and fetchTags options', () => {
     jest.restoreAllMocks()
   })
 
-  it('should call execGit with the correct arguments when fetchDepth is 0 and fetchTags is true', async () => {
+  it('should call execGit with the correct arguments when fetchDepth is 0', async () => {
     jest.spyOn(exec, 'exec').mockImplementation(mockExec)
     const workingDirectory = 'test'
     const lfs = false
@@ -122,45 +122,7 @@ describe('Test fetchDepth and fetchTags options', () => {
     const refSpec = ['refspec1', 'refspec2']
     const options = {
       filter: 'filterValue',
-      fetchDepth: 0,
-      fetchTags: true
-    }
-
-    await git.fetch(refSpec, options)
-
-    expect(mockExec).toHaveBeenCalledWith(
-      expect.any(String),
-      [
-        '-c',
-        'protocol.version=2',
-        'fetch',
-        '--prune',
-        '--no-recurse-submodules',
-        '--filter=filterValue',
-        'origin',
-        'refspec1',
-        'refspec2'
-      ],
-      expect.any(Object)
-    )
-  })
-
-  it('should call execGit with the correct arguments when fetchDepth is 0 and fetchTags is false', async () => {
-    jest.spyOn(exec, 'exec').mockImplementation(mockExec)
-
-    const workingDirectory = 'test'
-    const lfs = false
-    const doSparseCheckout = false
-    git = await commandManager.createCommandManager(
-      workingDirectory,
-      lfs,
-      doSparseCheckout
-    )
-    const refSpec = ['refspec1', 'refspec2']
-    const options = {
-      filter: 'filterValue',
-      fetchDepth: 0,
-      fetchTags: false
+      fetchDepth: 0
     }
 
     await git.fetch(refSpec, options)
@@ -183,7 +145,45 @@ describe('Test fetchDepth and fetchTags options', () => {
     )
   })
 
-  it('should call execGit with the correct arguments when fetchDepth is 1 and fetchTags is false', async () => {
+  it('should call execGit with the correct arguments when fetchDepth is 0 and refSpec includes tags', async () => {
+    jest.spyOn(exec, 'exec').mockImplementation(mockExec)
+
+    const workingDirectory = 'test'
+    const lfs = false
+    const doSparseCheckout = false
+    git = await commandManager.createCommandManager(
+      workingDirectory,
+      lfs,
+      doSparseCheckout
+    )
+    const refSpec = ['refspec1', 'refspec2', '+refs/tags/*:refs/tags/*']
+    const options = {
+      filter: 'filterValue',
+      fetchDepth: 0
+    }
+
+    await git.fetch(refSpec, options)
+
+    expect(mockExec).toHaveBeenCalledWith(
+      expect.any(String),
+      [
+        '-c',
+        'protocol.version=2',
+        'fetch',
+        '--no-tags',
+        '--prune',
+        '--no-recurse-submodules',
+        '--filter=filterValue',
+        'origin',
+        'refspec1',
+        'refspec2',
+        '+refs/tags/*:refs/tags/*'
+      ],
+      expect.any(Object)
+    )
+  })
+
+  it('should call execGit with the correct arguments when fetchDepth is 1', async () => {
     jest.spyOn(exec, 'exec').mockImplementation(mockExec)
 
     const workingDirectory = 'test'
@@ -197,8 +197,7 @@ describe('Test fetchDepth and fetchTags options', () => {
     const refSpec = ['refspec1', 'refspec2']
     const options = {
       filter: 'filterValue',
-      fetchDepth: 1,
-      fetchTags: false
+      fetchDepth: 1
     }
 
     await git.fetch(refSpec, options)
@@ -222,7 +221,7 @@ describe('Test fetchDepth and fetchTags options', () => {
     )
   })
 
-  it('should call execGit with the correct arguments when fetchDepth is 1 and fetchTags is true', async () => {
+  it('should call execGit with the correct arguments when fetchDepth is 1 and refSpec includes tags', async () => {
     jest.spyOn(exec, 'exec').mockImplementation(mockExec)
 
     const workingDirectory = 'test'
@@ -233,11 +232,10 @@ describe('Test fetchDepth and fetchTags options', () => {
       lfs,
       doSparseCheckout
     )
-    const refSpec = ['refspec1', 'refspec2']
+    const refSpec = ['refspec1', 'refspec2', '+refs/tags/*:refs/tags/*']
     const options = {
       filter: 'filterValue',
-      fetchDepth: 1,
-      fetchTags: true
+      fetchDepth: 1
     }
 
     await git.fetch(refSpec, options)
@@ -248,13 +246,15 @@ describe('Test fetchDepth and fetchTags options', () => {
         '-c',
         'protocol.version=2',
         'fetch',
+        '--no-tags',
         '--prune',
         '--no-recurse-submodules',
         '--filter=filterValue',
         '--depth=1',
         'origin',
         'refspec1',
-        'refspec2'
+        'refspec2',
+        '+refs/tags/*:refs/tags/*'
       ],
       expect.any(Object)
     )
@@ -338,7 +338,7 @@ describe('Test fetchDepth and fetchTags options', () => {
     )
   })
 
-  it('should call execGit with the correct arguments when fetchTags is true and showProgress is true', async () => {
+  it('should call execGit with the correct arguments when showProgress is true and refSpec includes tags', async () => {
     jest.spyOn(exec, 'exec').mockImplementation(mockExec)
 
     const workingDirectory = 'test'
@@ -349,10 +349,9 @@ describe('Test fetchDepth and fetchTags options', () => {
       lfs,
       doSparseCheckout
     )
-    const refSpec = ['refspec1', 'refspec2']
+    const refSpec = ['refspec1', 'refspec2', '+refs/tags/*:refs/tags/*']
     const options = {
       filter: 'filterValue',
-      fetchTags: true,
       showProgress: true
     }
 
@@ -364,15 +363,134 @@ describe('Test fetchDepth and fetchTags options', () => {
         '-c',
         'protocol.version=2',
         'fetch',
+        '--no-tags',
         '--prune',
         '--no-recurse-submodules',
         '--progress',
         '--filter=filterValue',
         'origin',
         'refspec1',
-        'refspec2'
+        'refspec2',
+        '+refs/tags/*:refs/tags/*'
       ],
       expect.any(Object)
     )
   })
 })
+
+describe('git user-agent with orchestration ID', () => {
+  beforeEach(async () => {
+    jest.spyOn(fshelper, 'fileExistsSync').mockImplementation(jest.fn())
+    jest.spyOn(fshelper, 'directoryExistsSync').mockImplementation(jest.fn())
+  })
+
+  afterEach(() => {
+    jest.restoreAllMocks()
+    // Clean up environment variable to prevent test pollution
+    delete process.env['ACTIONS_ORCHESTRATION_ID']
+  })
+
+  it('should include orchestration ID in user-agent when ACTIONS_ORCHESTRATION_ID is set', async () => {
+    const orchId = 'test-orch-id-12345'
+    process.env['ACTIONS_ORCHESTRATION_ID'] = orchId
+
+    let capturedEnv: any = null
+    mockExec.mockImplementation((path, args, options) => {
+      if (args.includes('version')) {
+        options.listeners.stdout(Buffer.from('2.18'))
+      }
+      // Capture env on any command
+      capturedEnv = options.env
+      return 0
+    })
+    jest.spyOn(exec, 'exec').mockImplementation(mockExec)
+
+    const workingDirectory = 'test'
+    const lfs = false
+    const doSparseCheckout = false
+    git = await commandManager.createCommandManager(
+      workingDirectory,
+      lfs,
+      doSparseCheckout
+    )
+
+    // Call a git command to trigger env capture after user-agent is set
+    await git.init()
+
+    // Verify the user agent includes the orchestration ID
+    expect(git).toBeDefined()
+    expect(capturedEnv).toBeDefined()
+    expect(capturedEnv['GIT_HTTP_USER_AGENT']).toBe(
+      `git/2.18 (github-actions-checkout) actions_orchestration_id/${orchId}`
+    )
+  })
+
+  it('should sanitize invalid characters in orchestration ID', async () => {
+    const orchId = 'test (with) special/chars'
+    process.env['ACTIONS_ORCHESTRATION_ID'] = orchId
+
+    let capturedEnv: any = null
+    mockExec.mockImplementation((path, args, options) => {
+      if (args.includes('version')) {
+        options.listeners.stdout(Buffer.from('2.18'))
+      }
+      // Capture env on any command
+      capturedEnv = options.env
+      return 0
+    })
+    jest.spyOn(exec, 'exec').mockImplementation(mockExec)
+
+    const workingDirectory = 'test'
+    const lfs = false
+    const doSparseCheckout = false
+    git = await commandManager.createCommandManager(
+      workingDirectory,
+      lfs,
+      doSparseCheckout
+    )
+
+    // Call a git command to trigger env capture after user-agent is set
+    await git.init()
+
+    // Verify the user agent has sanitized orchestration ID (spaces, parentheses, slash replaced)
+    expect(git).toBeDefined()
+    expect(capturedEnv).toBeDefined()
+    expect(capturedEnv['GIT_HTTP_USER_AGENT']).toBe(
+      'git/2.18 (github-actions-checkout) actions_orchestration_id/test__with__special_chars'
+    )
+  })
+
+  it('should not modify user-agent when ACTIONS_ORCHESTRATION_ID is not set', async () => {
+    delete process.env['ACTIONS_ORCHESTRATION_ID']
+
+    let capturedEnv: any = null
+    mockExec.mockImplementation((path, args, options) => {
+      if (args.includes('version')) {
+        options.listeners.stdout(Buffer.from('2.18'))
+      }
+      // Capture env on any command
+      capturedEnv = options.env
+      return 0
+    })
+    jest.spyOn(exec, 'exec').mockImplementation(mockExec)
+
+    const workingDirectory = 'test'
+    const lfs = false
+    const doSparseCheckout = false
+    git = await commandManager.createCommandManager(
+      workingDirectory,
+      lfs,
+      doSparseCheckout
+    )
+
+    // Call a git command to trigger env capture after user-agent is set
+    await git.init()
+
+    // Verify the user agent does NOT contain orchestration ID
+    expect(git).toBeDefined()
+    expect(capturedEnv).toBeDefined()
+    expect(capturedEnv['GIT_HTTP_USER_AGENT']).toBe(
+      'git/2.18 (github-actions-checkout)'
+    )
+  })
+})

__test__/ref-helper.test.ts

@@ -152,7 +152,22 @@ describe('ref-helper tests', () => {
   it('getRefSpec sha + refs/tags/', async () => {
     const refSpec = refHelper.getRefSpec('refs/tags/my-tag', commit)
     expect(refSpec.length).toBe(1)
-    expect(refSpec[0]).toBe(`+${commit}:refs/tags/my-tag`)
+    expect(refSpec[0]).toBe(`+refs/tags/my-tag:refs/tags/my-tag`)
+  })
+
+  it('getRefSpec sha + refs/tags/ with fetchTags', async () => {
+    // When fetchTags is true, only include tags wildcard (specific tag is redundant)
+    const refSpec = refHelper.getRefSpec('refs/tags/my-tag', commit, true)
+    expect(refSpec.length).toBe(1)
+    expect(refSpec[0]).toBe('+refs/tags/*:refs/tags/*')
+  })
+
+  it('getRefSpec sha + refs/heads/ with fetchTags', async () => {
+    // When fetchTags is true, include both the branch refspec and tags wildcard
+    const refSpec = refHelper.getRefSpec('refs/heads/my/branch', commit, true)
+    expect(refSpec.length).toBe(2)
+    expect(refSpec[0]).toBe('+refs/tags/*:refs/tags/*')
+    expect(refSpec[1]).toBe(`+${commit}:refs/remotes/origin/my/branch`)
   })
 
   it('getRefSpec sha only', async () => {
@@ -168,6 +183,14 @@ describe('ref-helper tests', () => {
     expect(refSpec[1]).toBe('+refs/tags/my-ref*:refs/tags/my-ref*')
   })
 
+  it('getRefSpec unqualified ref only with fetchTags', async () => {
+    // When fetchTags is true, skip specific tag pattern since wildcard covers all
+    const refSpec = refHelper.getRefSpec('my-ref', '', true)
+    expect(refSpec.length).toBe(2)
+    expect(refSpec[0]).toBe('+refs/tags/*:refs/tags/*')
+    expect(refSpec[1]).toBe('+refs/heads/my-ref*:refs/remotes/origin/my-ref*')
+  })
+
   it('getRefSpec refs/heads/ only', async () => {
     const refSpec = refHelper.getRefSpec('refs/heads/my/branch', '')
     expect(refSpec.length).toBe(1)
@@ -187,4 +210,21 @@ describe('ref-helper tests', () => {
     expect(refSpec.length).toBe(1)
     expect(refSpec[0]).toBe('+refs/tags/my-tag:refs/tags/my-tag')
   })
+
+  it('getRefSpec refs/tags/ only with fetchTags', async () => {
+    // When fetchTags is true, only include tags wildcard (specific tag is redundant)
+    const refSpec = refHelper.getRefSpec('refs/tags/my-tag', '', true)
+    expect(refSpec.length).toBe(1)
+    expect(refSpec[0]).toBe('+refs/tags/*:refs/tags/*')
+  })
+
+  it('getRefSpec refs/heads/ only with fetchTags', async () => {
+    // When fetchTags is true, include both the branch refspec and tags wildcard
+    const refSpec = refHelper.getRefSpec('refs/heads/my/branch', '', true)
+    expect(refSpec.length).toBe(2)
+    expect(refSpec[0]).toBe('+refs/tags/*:refs/tags/*')
+    expect(refSpec[1]).toBe(
+      '+refs/heads/my/branch:refs/remotes/origin/my/branch'
+    )
+  })
 })

__test__/verify-fetch-tags.sh

@@ -0,0 +1,9 @@
+#!/bin/sh
+
+# Verify tags were fetched
+TAG_COUNT=$(git -C ./fetch-tags-test tag | wc -l)
+if [ "$TAG_COUNT" -eq 0 ]; then
+    echo "Expected tags to be fetched, but found none"
+    exit 1
+fi
+echo "Found $TAG_COUNT tags"

__test__/verify-worktree.sh

@@ -0,0 +1,51 @@
+#!/bin/bash
+set -e
+
+# Verify worktree credentials
+# This test verifies that git credentials work in worktrees created after checkout
+# Usage: verify-worktree.sh <checkout-path> <worktree-name>
+
+CHECKOUT_PATH="$1"
+WORKTREE_NAME="$2"
+
+if [ -z "$CHECKOUT_PATH" ] || [ -z "$WORKTREE_NAME" ]; then
+  echo "Usage: verify-worktree.sh <checkout-path> <worktree-name>"
+  exit 1
+fi
+
+cd "$CHECKOUT_PATH"
+
+# Add safe directory for container environments
+git config --global --add safe.directory "*" 2>/dev/null || true
+
+# Show the includeIf configuration
+echo "Git config includeIf entries:"
+git config --list --show-origin | grep -i include || true
+
+# Create the worktree
+echo "Creating worktree..."
+git worktree add "../$WORKTREE_NAME" HEAD --detach
+
+# Change to worktree directory
+cd "../$WORKTREE_NAME"
+
+# Verify we're in a worktree
+echo "Verifying worktree gitdir:"
+cat .git
+
+# Verify credentials are available in worktree by checking extraheader is configured
+echo "Checking credentials in worktree..."
+if git config --list --show-origin | grep -q "extraheader"; then
+  echo "Credentials are configured in worktree"
+else
+  echo "ERROR: Credentials are NOT configured in worktree"
+  echo "Full git config:"
+  git config --list --show-origin
+  exit 1
+fi
+
+# Verify fetch works in the worktree
+echo "Fetching in worktree..."
+git fetch origin
+
+echo "Worktree credentials test passed!"

dist/index.js

@@ -412,6 +412,9 @@ class GitAuthHelper {
                 // Configure host includeIf
                 const hostIncludeKey = `includeIf.gitdir:${gitDir}.path`;
                 yield this.git.config(hostIncludeKey, credentialsConfigPath);
+                // Configure host includeIf for worktrees
+                const hostWorktreeIncludeKey = `includeIf.gitdir:${gitDir}/worktrees/*.path`;
+                yield this.git.config(hostWorktreeIncludeKey, credentialsConfigPath);
                 // Container git directory
                 const workingDirectory = this.git.getWorkingDirectory();
                 const githubWorkspace = process.env['GITHUB_WORKSPACE'];
@@ -424,6 +427,9 @@ class GitAuthHelper {
                 // Configure container includeIf
                 const containerIncludeKey = `includeIf.gitdir:${containerGitDir}.path`;
                 yield this.git.config(containerIncludeKey, containerCredentialsPath);
+                // Configure container includeIf for worktrees
+                const containerWorktreeIncludeKey = `includeIf.gitdir:${containerGitDir}/worktrees/*.path`;
+                yield this.git.config(containerWorktreeIncludeKey, containerCredentialsPath);
             }
         });
     }
@@ -647,7 +653,6 @@ const fs = __importStar(__nccwpck_require__(7147));
 const fshelper = __importStar(__nccwpck_require__(7219));
 const io = __importStar(__nccwpck_require__(7436));
 const path = __importStar(__nccwpck_require__(1017));
-const refHelper = __importStar(__nccwpck_require__(8601));
 const regexpHelper = __importStar(__nccwpck_require__(3120));
 const retryHelper = __importStar(__nccwpck_require__(2155));
 const git_version_1 = __nccwpck_require__(3142);
@@ -825,9 +830,9 @@ class GitCommandManager {
     fetch(refSpec, options) {
         return __awaiter(this, void 0, void 0, function* () {
             const args = ['-c', 'protocol.version=2', 'fetch'];
-            if (!refSpec.some(x => x === refHelper.tagsRefSpec) && !options.fetchTags) {
-                args.push('--no-tags');
-            }
+            // Always use --no-tags for explicit control over tag fetching
+            // Tags are fetched explicitly via refspec when needed
+            args.push('--no-tags');
             args.push('--prune', '--no-recurse-submodules');
             if (options.showProgress) {
                 args.push('--progress');
@@ -1200,7 +1205,17 @@ class GitCommandManager {
                 }
             }
             // Set the user agent
-            const gitHttpUserAgent = `git/${this.gitVersion} (github-actions-checkout)`;
+            let gitHttpUserAgent = `git/${this.gitVersion} (github-actions-checkout)`;
+            // Append orchestration ID if set
+            const orchId = process.env['ACTIONS_ORCHESTRATION_ID'];
+            if (orchId) {
+                // Sanitize the orchestration ID to ensure it contains only valid characters
+                // Valid characters: 0-9, a-z, _, -, .
+                const sanitizedId = orchId.replace(/[^a-z0-9_.-]/gi, '_');
+                if (sanitizedId) {
+                    gitHttpUserAgent = `${gitHttpUserAgent} actions_orchestration_id/${sanitizedId}`;
+                }
+            }
             core.debug(`Set git useragent to: ${gitHttpUserAgent}`);
             this.gitEnv['GIT_HTTP_USER_AGENT'] = gitHttpUserAgent;
         });
@@ -1523,13 +1538,26 @@ function getSource(settings) {
                 if (!(yield refHelper.testRef(git, settings.ref, settings.commit))) {
                     refSpec = refHelper.getRefSpec(settings.ref, settings.commit);
                     yield git.fetch(refSpec, fetchOptions);
+                    // Verify the ref now matches. For branches, the targeted fetch above brings
+                    // in the specific commit. For tags (fetched by ref), this will fail if
+                    // the tag was moved after the workflow was triggered.
+                    if (!(yield refHelper.testRef(git, settings.ref, settings.commit))) {
+                        throw new Error(`The ref '${settings.ref}' does not point to the expected commit '${settings.commit}'. ` +
+                            `The ref may have been updated after the workflow was triggered.`);
+                    }
                 }
             }
             else {
                 fetchOptions.fetchDepth = settings.fetchDepth;
-                fetchOptions.fetchTags = settings.fetchTags;
-                const refSpec = refHelper.getRefSpec(settings.ref, settings.commit);
+                const refSpec = refHelper.getRefSpec(settings.ref, settings.commit, settings.fetchTags);
                 yield git.fetch(refSpec, fetchOptions);
+                // For tags, verify the ref still points to the expected commit.
+                // Tags are fetched by ref (not commit), so if a tag was moved after the
+                // workflow was triggered, we would silently check out the wrong commit.
+                if (!(yield refHelper.testRef(git, settings.ref, settings.commit))) {
+                    throw new Error(`The ref '${settings.ref}' does not point to the expected commit '${settings.commit}'. ` +
+                        `The ref may have been updated after the workflow was triggered.`);
+                }
             }
             core.endGroup();
             // Checkout info
@@ -2268,53 +2296,67 @@ function getRefSpecForAllHistory(ref, commit) {
     }
     return result;
 }
-function getRefSpec(ref, commit) {
+function getRefSpec(ref, commit, fetchTags) {
     if (!ref && !commit) {
         throw new Error('Args ref and commit cannot both be empty');
     }
     const upperRef = (ref || '').toUpperCase();
+    const result = [];
+    // When fetchTags is true, always include the tags refspec
+    if (fetchTags) {
+        result.push(exports.tagsRefSpec);
+    }
     // SHA
     if (commit) {
         // refs/heads
         if (upperRef.startsWith('REFS/HEADS/')) {
             const branch = ref.substring('refs/heads/'.length);
-            return [`+${commit}:refs/remotes/origin/${branch}`];
+            result.push(`+${commit}:refs/remotes/origin/${branch}`);
         }
         // refs/pull/
         else if (upperRef.startsWith('REFS/PULL/')) {
             const branch = ref.substring('refs/pull/'.length);
-            return [`+${commit}:refs/remotes/pull/${branch}`];
+            result.push(`+${commit}:refs/remotes/pull/${branch}`);
         }
         // refs/tags/
         else if (upperRef.startsWith('REFS/TAGS/')) {
-            return [`+${commit}:${ref}`];
+            if (!fetchTags) {
+                result.push(`+${ref}:${ref}`);
+            }
         }
         // Otherwise no destination ref
         else {
-            return [commit];
+            result.push(commit);
         }
     }
     // Unqualified ref, check for a matching branch or tag
     else if (!upperRef.startsWith('REFS/')) {
-        return [
-            `+refs/heads/${ref}*:refs/remotes/origin/${ref}*`,
-            `+refs/tags/${ref}*:refs/tags/${ref}*`
-        ];
+        result.push(`+refs/heads/${ref}*:refs/remotes/origin/${ref}*`);
+        if (!fetchTags) {
+            result.push(`+refs/tags/${ref}*:refs/tags/${ref}*`);
+        }
     }
     // refs/heads/
     else if (upperRef.startsWith('REFS/HEADS/')) {
         const branch = ref.substring('refs/heads/'.length);
-        return [`+${ref}:refs/remotes/origin/${branch}`];
+        result.push(`+${ref}:refs/remotes/origin/${branch}`);
     }
     // refs/pull/
     else if (upperRef.startsWith('REFS/PULL/')) {
         const branch = ref.substring('refs/pull/'.length);
-        return [`+${ref}:refs/remotes/pull/${branch}`];
+        result.push(`+${ref}:refs/remotes/pull/${branch}`);
     }
     // refs/tags/
-    else {
-        return [`+${ref}:${ref}`];
+    else if (upperRef.startsWith('REFS/TAGS/')) {
+        if (!fetchTags) {
+            result.push(`+${ref}:${ref}`);
+        }
     }
+    // Other refs
+    else {
+        result.push(`+${ref}:${ref}`);
+    }
+    return result;
 }
 /**
  * Tests whether the initial fetch created the ref at the expected commit
@@ -2350,7 +2392,9 @@ function testRef(git, ref, commit) {
         // refs/tags/
         else if (upperRef.startsWith('REFS/TAGS/')) {
             const tagName = ref.substring('refs/tags/'.length);
-            return ((yield git.tagExists(tagName)) && commit === (yield git.revParse(ref)));
+            // Use ^{commit} to dereference annotated tags to their underlying commit
+            return ((yield git.tagExists(tagName)) &&
+                commit === (yield git.revParse(`${ref}^{commit}`)));
         }
         // Unexpected
         else {

src/git-auth-helper.ts

@@ -374,6 +374,10 @@ class GitAuthHelper {
       const hostIncludeKey = `includeIf.gitdir:${gitDir}.path`
       await this.git.config(hostIncludeKey, credentialsConfigPath)
 
+      // Configure host includeIf for worktrees
+      const hostWorktreeIncludeKey = `includeIf.gitdir:${gitDir}/worktrees/*.path`
+      await this.git.config(hostWorktreeIncludeKey, credentialsConfigPath)
+
       // Container git directory
       const workingDirectory = this.git.getWorkingDirectory()
       const githubWorkspace = process.env['GITHUB_WORKSPACE']
@@ -395,6 +399,13 @@ class GitAuthHelper {
       // Configure container includeIf
       const containerIncludeKey = `includeIf.gitdir:${containerGitDir}.path`
       await this.git.config(containerIncludeKey, containerCredentialsPath)
+
+      // Configure container includeIf for worktrees
+      const containerWorktreeIncludeKey = `includeIf.gitdir:${containerGitDir}/worktrees/*.path`
+      await this.git.config(
+        containerWorktreeIncludeKey,
+        containerCredentialsPath
+      )
     }
   }
 

src/git-command-manager.ts

@@ -37,7 +37,6 @@ export interface IGitCommandManager {
     options: {
       filter?: string
       fetchDepth?: number
-      fetchTags?: boolean
       showProgress?: boolean
     }
   ): Promise<void>
@@ -280,14 +279,13 @@ class GitCommandManager {
     options: {
       filter?: string
       fetchDepth?: number
-      fetchTags?: boolean
       showProgress?: boolean
     }
   ): Promise<void> {
     const args = ['-c', 'protocol.version=2', 'fetch']
-    if (!refSpec.some(x => x === refHelper.tagsRefSpec) && !options.fetchTags) {
-      args.push('--no-tags')
-    }
+    // Always use --no-tags for explicit control over tag fetching
+    // Tags are fetched explicitly via refspec when needed
+    args.push('--no-tags')
 
     args.push('--prune', '--no-recurse-submodules')
     if (options.showProgress) {
@@ -730,7 +728,19 @@ class GitCommandManager {
       }
     }
     // Set the user agent
-    const gitHttpUserAgent = `git/${this.gitVersion} (github-actions-checkout)`
+    let gitHttpUserAgent = `git/${this.gitVersion} (github-actions-checkout)`
+
+    // Append orchestration ID if set
+    const orchId = process.env['ACTIONS_ORCHESTRATION_ID']
+    if (orchId) {
+      // Sanitize the orchestration ID to ensure it contains only valid characters
+      // Valid characters: 0-9, a-z, _, -, .
+      const sanitizedId = orchId.replace(/[^a-z0-9_.-]/gi, '_')
+      if (sanitizedId) {
+        gitHttpUserAgent = `${gitHttpUserAgent} actions_orchestration_id/${sanitizedId}`
+      }
+    }
+
     core.debug(`Set git useragent to: ${gitHttpUserAgent}`)
     this.gitEnv['GIT_HTTP_USER_AGENT'] = gitHttpUserAgent
   }

src/git-source-provider.ts

@@ -159,7 +159,6 @@ export async function getSource(settings: IGitSourceSettings): Promise<void> {
     const fetchOptions: {
       filter?: string
       fetchDepth?: number
-      fetchTags?: boolean
       showProgress?: boolean
     } = {}
 
@@ -182,12 +181,35 @@ export async function getSource(settings: IGitSourceSettings): Promise<void> {
       if (!(await refHelper.testRef(git, settings.ref, settings.commit))) {
         refSpec = refHelper.getRefSpec(settings.ref, settings.commit)
         await git.fetch(refSpec, fetchOptions)
+
+        // Verify the ref now matches. For branches, the targeted fetch above brings
+        // in the specific commit. For tags (fetched by ref), this will fail if
+        // the tag was moved after the workflow was triggered.
+        if (!(await refHelper.testRef(git, settings.ref, settings.commit))) {
+          throw new Error(
+            `The ref '${settings.ref}' does not point to the expected commit '${settings.commit}'. ` +
+              `The ref may have been updated after the workflow was triggered.`
+          )
+        }
       }
     } else {
       fetchOptions.fetchDepth = settings.fetchDepth
-      fetchOptions.fetchTags = settings.fetchTags
-      const refSpec = refHelper.getRefSpec(settings.ref, settings.commit)
+      const refSpec = refHelper.getRefSpec(
+        settings.ref,
+        settings.commit,
+        settings.fetchTags
+      )
       await git.fetch(refSpec, fetchOptions)
+
+      // For tags, verify the ref still points to the expected commit.
+      // Tags are fetched by ref (not commit), so if a tag was moved after the
+      // workflow was triggered, we would silently check out the wrong commit.
+      if (!(await refHelper.testRef(git, settings.ref, settings.commit))) {
+        throw new Error(
+          `The ref '${settings.ref}' does not point to the expected commit '${settings.commit}'. ` +
+            `The ref may have been updated after the workflow was triggered.`
+        )
+      }
     }
     core.endGroup()
 

src/misc/generate-docs.ts

@@ -120,7 +120,7 @@ function updateUsage(
 }
 
 updateUsage(
-  'actions/checkout@v5',
+  'actions/checkout@v6',
   path.join(__dirname, '..', '..', 'action.yml'),
   path.join(__dirname, '..', '..', 'README.md')
 )

src/ref-helper.ts

@@ -76,55 +76,75 @@ export function getRefSpecForAllHistory(ref: string, commit: string): string[] {
   return result
 }
 
-export function getRefSpec(ref: string, commit: string): string[] {
+export function getRefSpec(
+  ref: string,
+  commit: string,
+  fetchTags?: boolean
+): string[] {
   if (!ref && !commit) {
     throw new Error('Args ref and commit cannot both be empty')
   }
 
   const upperRef = (ref || '').toUpperCase()
+  const result: string[] = []
+
+  // When fetchTags is true, always include the tags refspec
+  if (fetchTags) {
+    result.push(tagsRefSpec)
+  }
 
   // SHA
   if (commit) {
     // refs/heads
     if (upperRef.startsWith('REFS/HEADS/')) {
       const branch = ref.substring('refs/heads/'.length)
-      return [`+${commit}:refs/remotes/origin/${branch}`]
+      result.push(`+${commit}:refs/remotes/origin/${branch}`)
     }
     // refs/pull/
     else if (upperRef.startsWith('REFS/PULL/')) {
       const branch = ref.substring('refs/pull/'.length)
-      return [`+${commit}:refs/remotes/pull/${branch}`]
+      result.push(`+${commit}:refs/remotes/pull/${branch}`)
     }
     // refs/tags/
     else if (upperRef.startsWith('REFS/TAGS/')) {
-      return [`+${commit}:${ref}`]
+      if (!fetchTags) {
+        result.push(`+${ref}:${ref}`)
+      }
     }
     // Otherwise no destination ref
     else {
-      return [commit]
+      result.push(commit)
     }
   }
   // Unqualified ref, check for a matching branch or tag
   else if (!upperRef.startsWith('REFS/')) {
-    return [
-      `+refs/heads/${ref}*:refs/remotes/origin/${ref}*`,
-      `+refs/tags/${ref}*:refs/tags/${ref}*`
-    ]
+    result.push(`+refs/heads/${ref}*:refs/remotes/origin/${ref}*`)
+    if (!fetchTags) {
+      result.push(`+refs/tags/${ref}*:refs/tags/${ref}*`)
+    }
   }
   // refs/heads/
   else if (upperRef.startsWith('REFS/HEADS/')) {
     const branch = ref.substring('refs/heads/'.length)
-    return [`+${ref}:refs/remotes/origin/${branch}`]
+    result.push(`+${ref}:refs/remotes/origin/${branch}`)
   }
   // refs/pull/
   else if (upperRef.startsWith('REFS/PULL/')) {
     const branch = ref.substring('refs/pull/'.length)
-    return [`+${ref}:refs/remotes/pull/${branch}`]
+    result.push(`+${ref}:refs/remotes/pull/${branch}`)
   }
   // refs/tags/
-  else {
-    return [`+${ref}:${ref}`]
+  else if (upperRef.startsWith('REFS/TAGS/')) {
+    if (!fetchTags) {
+      result.push(`+${ref}:${ref}`)
+    }
   }
+  // Other refs
+  else {
+    result.push(`+${ref}:${ref}`)
+  }
+
+  return result
 }
 
 /**
@@ -170,8 +190,10 @@ export async function testRef(
   // refs/tags/
   else if (upperRef.startsWith('REFS/TAGS/')) {
     const tagName = ref.substring('refs/tags/'.length)
+    // Use ^{commit} to dereference annotated tags to their underlying commit
     return (
-      (await git.tagExists(tagName)) && commit === (await git.revParse(ref))
+      (await git.tagExists(tagName)) &&
+      commit === (await git.revParse(`${ref}^{commit}`))
     )
   }
   // Unexpected