filesystem

type EditedFileSystem struct {
	BaseFS FileSystem
	Edits  map[string]*text.EditSet
}

type FileSystem interface {
	// ReadDir returns a slice of os.FileInfo, sorted by Name,
	// describing the content of the named directory.
	ReadDir(dir string) ([]os.FileInfo, error)

	// OpenFile opens a file (not a directory) for reading.
	OpenFile(path string) (io.ReadCloser, error)

	// OverwriteFile opens a file for writing.  It is an error if the
	// file does not already exist.
	OverwriteFile(path string) (io.WriteCloser, error)

	// CreateFile creates a text file with the given contents and default
	// permissions.
	CreateFile(path, contents string) error

	// Rename changes the name of a file or directory.  newName should be a
	// bare name, not including a directory prefix; the existing file will
	// be renamed within its existing parent directory.
	Rename(path, newName string) error

	// Remove deletes a file or an empty directory.
	Remove(path string) error
}

type LocalFileSystem struct{}