def validate_configured_sources!
      Gem.sources.each_source do |src|
        begin
          src.load_specs(:released)
        rescue Gem::Exception => source_error
          if ENV["VAGRANT_ALLOW_PLUGIN_SOURCE_ERRORS"]
            @logger.warn("Failed to load configured plugin source: #{src}!")
            @logger.warn("Error received attempting to load source (#{src}): #{source_error}")
            @logger.warn("Ignoring plugin source load failure due user request via env variable")
          else
            @logger.error("Failed to load configured plugin source `#{src}`: #{source_error}")
            raise Vagrant::Errors::PluginSourceError,
              source: src.uri.to_s,
              error_msg: source_error.message
          end
        end
      end
    end
def validate_configured_sources!
      Gem.sources.each_source do |src|
        begin
          src.load_specs(:released)
        rescue Gem::Exception => source_error
          if ENV["VAGRANT_ALLOW_PLUGIN_SOURCE_ERRORS"]
            @logger.warn("Failed to load configured plugin source: #{src}!")
            @logger.warn("Error received attempting to load source (#{src}): #{source_error}")
            @logger.warn("Ignoring plugin source load failure due user request via env variable")
          else
            @logger.error("Failed to load configured plugin source `#{src}`: #{source_error}")
            raise Vagrant::Errors::PluginSourceError,
              source: src.uri.to_s,
              error_msg: source_error.message
          end
        end
      end
    end
Iterates each configured RubyGem source to validate that it is properly
 available. If source is unavailable an exception is raised.