You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: auth.rs
    path of file: ./repos/deno/cli/tools/registry
    
    the code of the file until where you have to start completion: // Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.

use std::io::IsTerminal;

use deno_core::anyhow;
use deno_core::anyhow::bail;
use deno_core::error::AnyError;

pub enum AuthMethod {
  Interactive,
  Token(String),
  Oidc(OidcConfig),
}

pub struct OidcConfig {
  pub url: String,
  pub token: String,
}

pub(crate) fn is_gha() -> bool {
  std::env::var("GITHUB_ACTIONS").unwrap
    
fn get_gh_oidc_env_vars() -> Option<Result<(String, String), AnyError>> {
  if std::env::var("GITHUB_ACTIONS").unwrap_or_default() == "true" {
    let url = std::env::var("ACTIONS_ID_TOKEN_REQUEST_URL");
    let token = std::env::var("ACTIONS_ID_TOKEN_REQUEST_TOKEN");
    match (url, token) {
        (Ok(url), Ok(token)) => Some(Ok((url, token))),
        (Err(_), Err(_)) => Some(Err(anyhow::anyhow!(
          "No means to authenticate. Pass a token to `--token`, or enable tokenless publishing from GitHub Actions using OIDC. Learn more at https://deno.co/ghoidc"
        ))),
        _ => None,
      }
  } else {
    None
  }
}