Gem::SpecificationPolicy#validate_name

# File tmp/rubies/ruby-3.0.5/lib/rubygems/specification_policy.rb, line 272
def validate_name
  name = @specification.name

  if !name.is_a?(String)
    error "invalid value for attribute name: \"#{name.inspect}\" must be a string"
  elsif name !~ /[a-zA-Z]/
    error "invalid value for attribute name: #{name.dump} must include at least one letter"
  elsif name !~ VALID_NAME_PATTERN
    error "invalid value for attribute name: #{name.dump} can only include letters, numbers, dashes, and underscores"
  elsif name =~ SPECIAL_CHARACTERS
    error "invalid value for attribute name: #{name.dump} can not begin with a period, dash, or underscore"
  end
end