Invalid redirection on branches with # in their name

[k0ral]

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Bug

Body

I've created a repository to showcase the issue, where:

1. I created branch branch-name
2. I renamed branch branch-name into branch-name#42

Scenario

Send HTTP GET to https://api.github.com/repos/k0ral/test-branch-redirection/branches/branch-name and follow redirections until you get a valid HTTP 200 response.

Current behavior

1. Request to https://api.github.com/repos/k0ral/test-branch-redirection/branches/branch-name gets an HTTP 301 response with Location header set to https://api.github.com/repos/k0ral/test-branch-redirection/branches/branch-name#42 (notice that the # character isn't escaped)
2. Following redirection: request to https://api.github.com/repos/k0ral/test-branch-redirection/branches/branch-name#42 gets an HTTP 301 response with Location header set to https://api.github.com/repos/k0ral/test-branch-redirection/branches/branch-name#42 (i.e. itself)
3. ... Loop forever

Desired behavior

1. Request to https://api.github.com/repos/k0ral/test-branch-redirection/branches/branch-name gets an HTTP 301 response with Location header set to https://api.github.com/repos/k0ral/test-branch-redirection/branches/branch-name%2342 (# is escaped)
2. Following redirection: request to https://api.github.com/repos/k0ral/test-branch-redirection/branches/branch-name%2342 gets an HTTP 200 response

Analysis

The unescaped # character is interpreted as an URL anchor, ignored by the API, so https://api.github.com/repos/k0ral/test-branch-redirection/branches/branch-name#42 is equivalent to https://api.github.com/repos/k0ral/test-branch-redirection/branches/branch-name , hence the infinite redirection.

[ghostinhershell]

Hi @k0ral,

Thanks so much for reaching out in our community. It sounds like this may be expected behavior.

When using a CLI, you might have situations where a branch or tag name contains special characters that have a special meaning for your shell environment. To use these characters safely in a Git command, they must be quoted or escaped, otherwise the command may have unintended effects: Dealing with special characters in branch and tag names.