plumbing/format/idxfile: add new Index and MemoryIndex

Signed-off-by: Miguel Molina <miguel@erizocosmi.co>

1 files changed, 0 insertions, 125 deletions

diff --git a/plumbing/format/packfile/index.go b/plumbing/format/packfile/index.go
deleted file mode 100644
index 021b2d1..0000000
--- a/plumbing/format/packfile/index.go
+++ /dev/null
@@ -1,125 +0,0 @@
-package packfile
-
-import (
-	"sort"
-
-	"gopkg.in/src-d/go-git.v4/plumbing"
-	"gopkg.in/src-d/go-git.v4/plumbing/format/idxfile"
-)
-
-// Index is an in-memory representation of a packfile index.
-// This uses idxfile.Idxfile under the hood to obtain indexes from .idx files
-// or to store them.
-type Index struct {
-	byHash   map[plumbing.Hash]*idxfile.Entry
-	byOffset []*idxfile.Entry // sorted by their offset
-}
-
-// NewIndex creates a new empty index with the given size. Size is a hint and
-// can be 0. It is recommended to set it to the number of objects to be indexed
-// if it is known beforehand (e.g. reading from a packfile).
-func NewIndex(size int) *Index {
-	return &Index{
-		byHash:   make(map[plumbing.Hash]*idxfile.Entry, size),
-		byOffset: make([]*idxfile.Entry, 0, size),
-	}
-}
-
-// NewIndexFromIdxFile creates a new Index from an idxfile.IdxFile.
-func NewIndexFromIdxFile(idxf *idxfile.Idxfile) *Index {
-	idx := &Index{
-		byHash:   make(map[plumbing.Hash]*idxfile.Entry, idxf.ObjectCount),
-		byOffset: make([]*idxfile.Entry, 0, idxf.ObjectCount),
-	}
-	sorted := true
-	for i, e := range idxf.Entries {
-		idx.addUnsorted(e)
-		if i > 0 && idx.byOffset[i-1].Offset >= e.Offset {
-			sorted = false
-		}
-	}
-
-	// If the idxfile was loaded from a regular packfile index
-	// then it will already be in offset order, in which case we
-	// can avoid doing a relatively expensive idempotent sort.
-	if !sorted {
-		sort.Sort(orderByOffset(idx.byOffset))
-	}
-
-	return idx
-}
-
-// orderByOffset is a sort.Interface adapter that arranges
-// a slice of entries by their offset.
-type orderByOffset []*idxfile.Entry
-
-func (o orderByOffset) Len() int           { return len(o) }
-func (o orderByOffset) Less(i, j int) bool { return o[i].Offset < o[j].Offset }
-func (o orderByOffset) Swap(i, j int)      { o[i], o[j] = o[j], o[i] }
-
-// Add adds a new Entry with the given values to the index.
-func (idx *Index) Add(h plumbing.Hash, offset uint64, crc32 uint32) {
-	e := &idxfile.Entry{
-		Hash:   h,
-		Offset: offset,
-		CRC32:  crc32,
-	}
-	idx.byHash[e.Hash] = e
-
-	// Find the right position in byOffset.
-	// Look for the first position whose offset is *greater* than e.Offset.
-	i := sort.Search(len(idx.byOffset), func(i int) bool {
-		return idx.byOffset[i].Offset > offset
-	})
-	if i == len(idx.byOffset) {
-		// Simple case: add it to the end.
-		idx.byOffset = append(idx.byOffset, e)
-		return
-	}
-	// Harder case: shift existing entries down by one to make room.
-	// Append a nil entry first so we can use existing capacity in case
-	// the index was carefully preallocated.
-	idx.byOffset = append(idx.byOffset, nil)
-	copy(idx.byOffset[i+1:], idx.byOffset[i:len(idx.byOffset)-1])
-	idx.byOffset[i] = e
-}
-
-func (idx *Index) addUnsorted(e *idxfile.Entry) {
-	idx.byHash[e.Hash] = e
-	idx.byOffset = append(idx.byOffset, e)
-}
-
-// LookupHash looks an entry up by its hash. An idxfile.Entry is returned and
-// a bool, which is true if it was found or false if it wasn't.
-func (idx *Index) LookupHash(h plumbing.Hash) (*idxfile.Entry, bool) {
-	e, ok := idx.byHash[h]
-	return e, ok
-}
-
-// LookupHash looks an entry up by its offset in the packfile. An idxfile.Entry
-// is returned and a bool, which is true if it was found or false if it wasn't.
-func (idx *Index) LookupOffset(offset uint64) (*idxfile.Entry, bool) {
-	i := sort.Search(len(idx.byOffset), func(i int) bool {
-		return idx.byOffset[i].Offset >= offset
-	})
-	if i >= len(idx.byOffset) || idx.byOffset[i].Offset != offset {
-		return nil, false // not present
-	}
-	return idx.byOffset[i], true
-}
-
-// Size returns the number of entries in the index.
-func (idx *Index) Size() int {
-	return len(idx.byHash)
-}
-
-// ToIdxFile converts the index to an idxfile.Idxfile, which can then be used
-// to serialize.
-func (idx *Index) ToIdxFile() *idxfile.Idxfile {
-	idxf := idxfile.NewIdxfile()
-	for _, e := range idx.byHash {
-		idxf.Entries = append(idxf.Entries, e)
-	}
-
-	return idxf
-}