This method is only available on newer versions.
The first available version (v2_6_3) is shown here.
source(name)
public
@return [Class] that handles the source. The calss includes
API::Source
# File lib/bundler/plugin.rb, line 139
def source(name)
raise UnknownSourceError, "Source #{name} not found" unless source? name
load_plugin(index.source_plugin(name)) unless @sources.key? name
@sources[name]
end