…overlaps the exact name
Removed FIXME comment since Gem::Package checks a hash checksum now.
Before accessing the core API (indexes, specs, .gem files), RubyGems will query the source via a DNS SRV record, to see if there is a specific API host to connect to rather than directly to the source itself. This allows for the usage of short, simple source names (like https://rubygems.org) with specific api endpoint names, which improves load balancing.
This is a little more aggressive than the pull request's diff because if there is an error fetching the index for a source, it doesn't fall back to the cache. This seems like the right behavior because if the index can't be fetched, the likely good that the spec and .gem can be is very slim.
The -v option applies to all gems specified, but it's common to need to install different versions of the respective gems.
Setting :disable_default_gem_server: true in the config file would wrongly use the :verbose flag instead.