Git 2.17.0窄克隆：仅拉取单个文件并提交的实操问题

Great question! Let's walk through exactly how to pull off editing a single file from a large repo with minimal bandwidth usage, while avoiding that frustrating "does not appear to be a git repository" error. Since you're on Git 2.17.0 (an older but still functional version), we'll work within its feature set.

Step 1: Fix the Clone Command & Avoid Repository Errors #

First, let's nail down the initial clone command—this is usually where that "not a git repo" error originates:

• If srv.bare is a bare repository, your path is correct. If it's a regular non-bare repo, you need to point to its .git subdirectory instead (e.g., file://$(pwd)/srv/.git), since Git needs to interact with the repo's internal metadata files.
• Update your clone command to include --depth 1 while keeping the narrow clone filters:

git clone --no-checkout --filter=blob:none --depth 1 "file://$(pwd)/srv.bare" pc1
cd pc1

This pulls only the latest commit's metadata (no actual file content yet) to save maximum space and bandwidth.

Step 2: Sparse Checkout to Fetch Only Your Target File #

Git 2.17.0 doesn't have the modern git sparse-checkout init shortcut, so we'll set up sparse checkout manually to grab just the file you need:

1. Enable sparse checkout in the repo config:

git config core.sparseCheckout true

2. Specify the exact file path you want to fetch. For example, if your target file is src/utils/helpers.js, run:

echo "src/utils/helpers.js" >> .git/info/sparse-checkout

3. Check out the file to your working directory:

git checkout HEAD

Now you'll only see your target file in the pc1 directory—no other repo content is pulled down.

Step 3: Edit, Commit, and Push Your Changes #

Shallow clones (created with --depth 1) block pushes by default, so we need to tweak a few configs to allow pushing your single-file change:

1. Set up push defaults to target the correct remote branch:

git config push.default current
git config remote.origin.push HEAD

2. Edit your file as needed, then commit the change:

git add src/utils/helpers.js
git commit -m "Update helper function logic"

3. Push the commit to the remote repo:

git push

Note: If the remote repo has recent commits you don't have (since we're using a shallow clone), you might hit a non-fast-forward error. In that case, you'd need to fetch the latest changes first, but if you're the only one editing this file, this workflow should work smoothly.

Key Notes for Git 2.17.0 #

• The --filter=blob:none flag works with --depth 1 here, but make sure your remote repo (local in this case) supports narrow clones—all local repos do, so this isn't an issue.
• Double-check your remote path if you still get the "not a git repo" error: bare repos typically end with .bare, but regular repos require the .git suffix in the URL.

内容的提问来源于stack exchange，提问作者Dan Jacobson