| package fsnoder |
| |
| import ( |
| "bytes" |
| "fmt" |
| "hash/fnv" |
| |
| "gopkg.in/src-d/go-git.v4/utils/merkletrie/noder" |
| ) |
| |
| // file values represent file-like noders in a merkle trie. |
| type file struct { |
| name string // relative |
| contents string |
| hash []byte // memoized |
| } |
| |
| // newFile returns a noder representing a file with the given contents. |
| func newFile(name, contents string) (*file, error) { |
| if name == "" { |
| return nil, fmt.Errorf("files cannot have empty names") |
| } |
| |
| return &file{ |
| name: name, |
| contents: contents, |
| }, nil |
| } |
| |
| // The hash of a file is just its contents. |
| // Empty files will have the fnv64 basis offset as its hash. |
| func (f *file) Hash() []byte { |
| if f.hash == nil { |
| h := fnv.New64a() |
| h.Write([]byte(f.contents)) // it nevers returns an error. |
| f.hash = h.Sum(nil) |
| } |
| |
| return f.hash |
| } |
| |
| func (f *file) Name() string { |
| return f.name |
| } |
| |
| func (f *file) IsDir() bool { |
| return false |
| } |
| |
| func (f *file) Children() ([]noder.Noder, error) { |
| return noder.NoChildren, nil |
| } |
| |
| func (f *file) NumChildren() (int, error) { |
| return 0, nil |
| } |
| |
| const ( |
| fileStartMark = '<' |
| fileEndMark = '>' |
| ) |
| |
| // String returns a string formated as: name<contents>. |
| func (f *file) String() string { |
| var buf bytes.Buffer |
| buf.WriteString(f.name) |
| buf.WriteRune(fileStartMark) |
| buf.WriteString(f.contents) |
| buf.WriteRune(fileEndMark) |
| |
| return buf.String() |
| } |