[BUG] Changing NPM version when on 7.23.0 ignores registry option

[yacoman89]

Is there an existing issue for this?

• I have searched the existing issues

Current Behavior

I use an internal network for development. Because of this, I have a mirror of the npm registry. After I updated npm to version 7.23.0 and attempted to downgrade npm to version 7.22.0 using npm install --global npm@7.22.0, I noticed the install would fail because npm was ignoring the registry I specified. This operation was forced to use the default registry https://registry.npmjs.org/npm during one of it's checks.

Expected Behavior

I would expect that if an alternative registry is provided, the npm install checks would use that registry and continue the install process.

Steps To Reproduce

1. In this environment...
   a. Any OS without an internet connection that uses a mirror of the npm registry on an internal network.
   b. Need to be using npm version 7.23.0.
2. With this config...

registry = "https://my.awesome.npm.mirror/npm"

3. Run npm install --global npm@7.22.0
4. See error...

npm ERR! code ENOTFOUND
npm ERR! syscall getaddrinfo
npm ERR! errno ENOTFOUND
npm ERR! network request to https://registry.npmjs.org/npm failed, reason getaddrinfo ENOTFOUND registry.npmjs.org
npm ERR! network This is a problem related to network connectivity.
npm ERR! network In most cases you are behind a proxy or have bad network settings.
npm ERR! network
npm ERR! network If you are behind a proxy, please make sure that the
npm ERR! network 'proxy' config is set properly.  See: 'npm help config'

Environment

• OS: Any
• Node: v12.14.0
• npm: 7.23.0