supply

type Command interface {
	Run(cmd *exec.Cmd) error
}

type Installer interface {
	InstallDependency(libbuildpack.Dependency, string) error
}

type Manifest interface {
	AllDependencyVersions(string) []string
}

type Package struct {
	Name string `yaml:"name"`
}

type Packages struct {
	Packages []Source `yaml:"packages"`
}

type Source struct {
	CranMirror string    `yaml:"cran_mirror"`
	Packages   []Package `yaml:"packages"`
	Ncpus      int       `yaml:"num_threads"`
}

type Stager interface {
	BuildDir() string
	DepDir() string
	DepsDir() string
	DepsIdx() string
	LinkDirectoryInDepDir(string, string) error
}

type Supplier struct {
	Stager    Stager
	Manifest  Manifest
	Installer Installer
	Command   Command
	Log       *libbuildpack.Logger
}