Since I have no environment of GitHub Enterprise Server, I was looking forward to this issue, thanks!

We can modify the function setGithubToken to get a server domain from process.env['GITHUB_SERVER_URL'].

• https://github.com/actions/checkout/blob/25a956c84d5dd820d28caab9f86b8d183aeeff3d/src/url-helper.ts#L22
• https://github.com/actions/checkout/blob/25a956c84d5dd820d28caab9f86b8d183aeeff3d/src/git-auth-helper.ts#L54

Those are also helpful for us.

export function getServerUrl(): URL {
  // todo: remove GITHUB_URL after support for GHES Alpha is no longer needed
  return new URL(
    process.env['GITHUB_SERVER_URL'] ||
      process.env['GITHUB_URL'] ||
      'https://github.com'
  )
}

const serverUrl = getServerUrl()

return `https://x-access-token:${githubToken}@${serverUrl.hostname}/${publishRepo}.git`;

Should we read the ENV variable or should it be handed into the action by an input?
I can PR both, what is the better design - I am a novice!?

The former is the best because GITHUB_SERVER_URL can provide a URL of a company's GitHub Enterprise Server.

The former is the best because GITHUB_SERVER_URL can provide a URL of a company's GitHub Enterprise Server.

On it, expect PR 🔄