[mod]: Bump gopkg.in/src-d/go-git.v4 from 4.8.0 to 4.10.0 (#6662)

Bumps [gopkg.in/src-d/go-git.v4](https://github.com/src-d/go-git) from 4.8.0 to 4.10.0.
- [Release notes](https://github.com/src-d/go-git/releases)
- [Commits](https://github.com/src-d/go-git/compare/v4.8.0...v4.10.0)

26 files changed, 594 insertions, 188 deletions

diff --git a/vendor/gopkg.in/src-d/go-git.v4/config/config.go b/vendor/gopkg.in/src-d/go-git.v4/config/config.go
index a637f6d709..2c3b8b9683 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/config/config.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/config/config.go
@@ -8,6 +8,7 @@ import (
 	"sort"
 	"strconv"
 
+	"gopkg.in/src-d/go-git.v4/internal/url"
 	format "gopkg.in/src-d/go-git.v4/plumbing/format/config"
 )
 
@@ -399,3 +400,7 @@ func (c *RemoteConfig) marshal() *format.Subsection {
 
 	return c.raw
 }
+
+func (c *RemoteConfig) IsFirstURLLocal() bool {
+	return url.IsLocalEndpoint(c.URLs[0])
+}
diff --git a/vendor/gopkg.in/src-d/go-git.v4/internal/url/url.go b/vendor/gopkg.in/src-d/go-git.v4/internal/url/url.go
new file mode 100644
index 0000000000..0f0d709d93
--- /dev/null
+++ b/vendor/gopkg.in/src-d/go-git.v4/internal/url/url.go
@@ -0,0 +1,37 @@
+package url
+
+import (
+	"regexp"
+)
+
+var (
+	isSchemeRegExp   = regexp.MustCompile(`^[^:]+://`)
+	scpLikeUrlRegExp = regexp.MustCompile(`^(?:(?P<user>[^@]+)@)?(?P<host>[^:\s]+):(?:(?P<port>[0-9]{1,5})/)?(?P<path>[^\\].*)$`)
+)
+
+// MatchesScheme returns true if the given string matches a URL-like
+// format scheme.
+func MatchesScheme(url string) bool {
+	return isSchemeRegExp.MatchString(url)
+}
+
+// MatchesScpLike returns true if the given string matches an SCP-like
+// format scheme.
+func MatchesScpLike(url string) bool {
+	return scpLikeUrlRegExp.MatchString(url)
+}
+
+// FindScpLikeComponents returns the user, host, port and path of the
+// given SCP-like URL.
+func FindScpLikeComponents(url string) (user, host, port, path string) {
+	m := scpLikeUrlRegExp.FindStringSubmatch(url)
+	return m[1], m[2], m[3], m[4]
+}
+
+// IsLocalEndpoint returns true if the given URL string specifies a
+// local file endpoint.  For example, on a Linux machine,
+// `/home/user/src/go-git` would match as a local endpoint, but
+// `https://github.com/src-d/go-git` would not.
+func IsLocalEndpoint(url string) bool {
+	return !MatchesScheme(url) && !MatchesScpLike(url)
+}
diff --git a/vendor/gopkg.in/src-d/go-git.v4/options.go b/vendor/gopkg.in/src-d/go-git.v4/options.go
index 5d10a88c35..ed7689ab3f 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/options.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/options.go
@@ -335,6 +335,11 @@ type LogOptions struct {
 	// Show only those commits in which the specified file was inserted/updated.
 	// It is equivalent to running `git log -- <file-name>`.
 	FileName *string
+
+	// Pretend as if all the refs in refs/, along with HEAD, are listed on the command line as <commit>.
+	// It is equivalent to running `git log --all`.
+	// If set on true, the From option will be ignored.
+	All bool
 }
 
 var (
diff --git a/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/common.go b/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/common.go
index 2b4acebdeb..0d9ed5447d 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/common.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/common.go
@@ -51,7 +51,13 @@ func WritePackfileToObjectStorage(
 	}
 
 	defer ioutil.CheckClose(w, &err)
-	_, err = io.Copy(w, packfile)
+
+	var n int64
+	n, err = io.Copy(w, packfile)
+	if err == nil && n == 0 {
+		return ErrEmptyPackfile
+	}
+
 	return err
 }
 
diff --git a/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/fsobject.go b/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/fsobject.go
index 330cb73c98..a268bce7ed 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/fsobject.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/fsobject.go
@@ -48,7 +48,7 @@ func NewFSObject(
 // Reader implements the plumbing.EncodedObject interface.
 func (o *FSObject) Reader() (io.ReadCloser, error) {
 	obj, ok := o.cache.Get(o.hash)
-	if ok {
+	if ok && obj != o {
 		reader, err := obj.Reader()
 		if err != nil {
 			return nil, err
diff --git a/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/packfile.go b/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/packfile.go
index 2166e0aa20..69b6e85d0c 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/packfile.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/packfile.go
@@ -21,6 +21,16 @@ var (
 	ErrZLib = NewError("zlib reading error")
 )
 
+// When reading small objects from packfile it is beneficial to do so at
+// once to exploit the buffered I/O. In many cases the objects are so small
+// that they were already loaded to memory when the object header was
+// loaded from the packfile. Wrapping in FSObject would cause this buffered
+// data to be thrown away and then re-read later, with the additional
+// seeking causing reloads from disk. Objects smaller than this threshold
+// are now always read into memory and stored in cache instead of being
+// wrapped in FSObject.
+const smallObjectThreshold = 16 * 1024
+
 // Packfile allows retrieving information from inside a packfile.
 type Packfile struct {
 	idxfile.Index
@@ -79,15 +89,7 @@ func (p *Packfile) GetByOffset(o int64) (plumbing.EncodedObject, error) {
 		}
 	}
 
-	if _, err := p.s.SeekFromStart(o); err != nil {
-		if err == io.EOF || isInvalid(err) {
-			return nil, plumbing.ErrObjectNotFound
-		}
-
-		return nil, err
-	}
-
-	return p.nextObject()
+	return p.objectAtOffset(o)
 }
 
 // GetSizeByOffset retrieves the size of the encoded object from the
@@ -105,7 +107,13 @@ func (p *Packfile) GetSizeByOffset(o int64) (size int64, err error) {
 	if err != nil {
 		return 0, err
 	}
-	return h.Length, nil
+	return p.getObjectSize(h)
+}
+
+func (p *Packfile) objectHeaderAtOffset(offset int64) (*ObjectHeader, error) {
+	h, err := p.s.SeekObjectHeader(offset)
+	p.s.pendingObject = nil
+	return h, err
 }
 
 func (p *Packfile) nextObjectHeader() (*ObjectHeader, error) {
@@ -154,11 +162,7 @@ func (p *Packfile) getObjectType(h *ObjectHeader) (typ plumbing.ObjectType, err
 		if baseType, ok := p.offsetToType[offset]; ok {
 			typ = baseType
 		} else {
-			if _, err = p.s.SeekFromStart(offset); err != nil {
-				return
-			}
-
-			h, err = p.nextObjectHeader()
+			h, err = p.objectHeaderAtOffset(offset)
 			if err != nil {
 				return
 			}
@@ -175,8 +179,8 @@ func (p *Packfile) getObjectType(h *ObjectHeader) (typ plumbing.ObjectType, err
 	return
 }
 
-func (p *Packfile) nextObject() (plumbing.EncodedObject, error) {
-	h, err := p.nextObjectHeader()
+func (p *Packfile) objectAtOffset(offset int64) (plumbing.EncodedObject, error) {
+	h, err := p.objectHeaderAtOffset(offset)
 	if err != nil {
 		if err == io.EOF || isInvalid(err) {
 			return nil, plumbing.ErrObjectNotFound
@@ -190,6 +194,13 @@ func (p *Packfile) nextObject() (plumbing.EncodedObject, error) {
 		return p.getNextObject(h)
 	}
 
+	// If the object is not a delta and it's small enough then read it
+	// completely into memory now since it is already read from disk
+	// into buffer anyway.
+	if h.Length <= smallObjectThreshold && h.Type != plumbing.OFSDeltaObject && h.Type != plumbing.REFDeltaObject {
+		return p.getNextObject(h)
+	}
+
 	hash, err := p.FindHash(h.Offset)
 	if err != nil {
 		return nil, err
@@ -233,11 +244,7 @@ func (p *Packfile) getObjectContent(offset int64) (io.ReadCloser, error) {
 		}
 	}
 
-	if _, err := p.s.SeekFromStart(offset); err != nil {
-		return nil, err
-	}
-
-	h, err := p.nextObjectHeader()
+	h, err := p.objectHeaderAtOffset(offset)
 	if err != nil {
 		return nil, err
 	}
@@ -329,8 +336,6 @@ func (p *Packfile) fillOFSDeltaObjectContent(obj plumbing.EncodedObject, offset
 		if err != nil {
 			return err
 		}
-
-		p.cachePut(base)
 	}
 
 	obj.SetType(base.Type())
diff --git a/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/parser.go b/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/parser.go
index 5a62d63bb0..71cbba9838 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/parser.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/parser.go
@@ -398,11 +398,7 @@ func (p *Parser) readData(o *objectInfo) ([]byte, error) {
 		return data, nil
 	}
 
-	if _, err := p.scanner.SeekFromStart(o.Offset); err != nil {
-		return nil, err
-	}
-
-	if _, err := p.scanner.NextObjectHeader(); err != nil {
+	if _, err := p.scanner.SeekObjectHeader(o.Offset); err != nil {
 		return nil, err
 	}
 
diff --git a/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/scanner.go b/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/scanner.go
index 6fc183b94f..614b0d1a8b 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/scanner.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/plumbing/format/packfile/scanner.go
@@ -138,14 +138,52 @@ func (s *Scanner) readCount() (uint32, error) {
 	return binary.ReadUint32(s.r)
 }
 
+// SeekObjectHeader seeks to specified offset and returns the ObjectHeader
+// for the next object in the reader
+func (s *Scanner) SeekObjectHeader(offset int64) (*ObjectHeader, error) {
+	// if seeking we assume that you are not interested in the header
+	if s.version == 0 {
+		s.version = VersionSupported
+	}
+
+	if _, err := s.r.Seek(offset, io.SeekStart); err != nil {
+		return nil, err
+	}
+
+	h, err := s.nextObjectHeader()
+	if err != nil {
+		return nil, err
+	}
+
+	h.Offset = offset
+	return h, nil
+}
+
 // NextObjectHeader returns the ObjectHeader for the next object in the reader
 func (s *Scanner) NextObjectHeader() (*ObjectHeader, error) {
-	defer s.Flush()
-
 	if err := s.doPending(); err != nil {
 		return nil, err
 	}
 
+	offset, err := s.r.Seek(0, io.SeekCurrent)
+	if err != nil {
+		return nil, err
+	}
+
+	h, err := s.nextObjectHeader()
+	if err != nil {
+		return nil, err
+	}
+
+	h.Offset = offset
+	return h, nil
+}
+
+// nextObjectHeader returns the ObjectHeader for the next object in the reader
+// without the Offset field
+func (s *Scanner) nextObjectHeader() (*ObjectHeader, error) {
+	defer s.Flush()
+
 	s.crc.Reset()
 
 	h := &ObjectHeader{}
@@ -308,7 +346,7 @@ var byteSlicePool = sync.Pool{
 // SeekFromStart sets a new offset from start, returns the old position before
 // the change.
 func (s *Scanner) SeekFromStart(offset int64) (previous int64, err error) {
-	// if seeking we assume that you are not interested on the header
+	// if seeking we assume that you are not interested in the header
 	if s.version == 0 {
 		s.version = VersionSupported
 	}
@@ -385,7 +423,7 @@ type bufferedSeeker struct {
 }
 
 func (r *bufferedSeeker) Seek(offset int64, whence int) (int64, error) {
-	if whence == io.SeekCurrent {
+	if whence == io.SeekCurrent && offset == 0 {
 		current, err := r.r.Seek(offset, whence)
 		if err != nil {
 			return current, err
diff --git a/vendor/gopkg.in/src-d/go-git.v4/plumbing/object/commit_walker.go b/vendor/gopkg.in/src-d/go-git.v4/plumbing/object/commit_walker.go
index 40ad2582bc..0eff059127 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/plumbing/object/commit_walker.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/plumbing/object/commit_walker.go
@@ -1,10 +1,12 @@
 package object
 
 import (
+	"container/list"
 	"io"
 
 	"gopkg.in/src-d/go-git.v4/plumbing"
 	"gopkg.in/src-d/go-git.v4/plumbing/storer"
+	"gopkg.in/src-d/go-git.v4/storage"
 )
 
 type commitPreIterator struct {
@@ -181,3 +183,145 @@ func (w *commitPostIterator) ForEach(cb func(*Commit) error) error {
 }
 
 func (w *commitPostIterator) Close() {}
+
+// commitAllIterator stands for commit iterator for all refs.
+type commitAllIterator struct {
+	// currCommit points to the current commit.
+	currCommit *list.Element
+}
+
+// NewCommitAllIter returns a new commit iterator for all refs.
+// repoStorer is a repo Storer used to get commits and references.
+// commitIterFunc is a commit iterator function, used to iterate through ref commits in chosen order
+func NewCommitAllIter(repoStorer storage.Storer, commitIterFunc func(*Commit) CommitIter) (CommitIter, error) {
+	commitsPath := list.New()
+	commitsLookup := make(map[plumbing.Hash]*list.Element)
+	head, err := storer.ResolveReference(repoStorer, plumbing.HEAD)
+	if err == nil {
+		err = addReference(repoStorer, commitIterFunc, head, commitsPath, commitsLookup)
+	}
+
+	if err != nil && err != plumbing.ErrReferenceNotFound {
+		return nil, err
+	}
+
+	// add all references along with the HEAD
+	refIter, err := repoStorer.IterReferences()
+	if err != nil {
+		return nil, err
+	}
+	defer refIter.Close()
+
+	for {
+		ref, err := refIter.Next()
+		if err == io.EOF {
+			break
+		}
+
+		if err == plumbing.ErrReferenceNotFound {
+			continue
+		}
+
+		if err != nil {
+			return nil, err
+		}
+
+		if err = addReference(repoStorer, commitIterFunc, ref, commitsPath, commitsLookup); err != nil {
+			return nil, err
+		}
+	}
+
+	return &commitAllIterator{commitsPath.Front()}, nil
+}
+
+func addReference(
+	repoStorer storage.Storer,
+	commitIterFunc func(*Commit) CommitIter,
+	ref *plumbing.Reference,
+	commitsPath *list.List,
+	commitsLookup map[plumbing.Hash]*list.Element) error {
+
+	_, exists := commitsLookup[ref.Hash()]
+	if exists {
+		// we already have it - skip the reference.
+		return nil
+	}
+
+	refCommit, _ := GetCommit(repoStorer, ref.Hash())
+	if refCommit == nil {
+		// if it's not a commit - skip it.
+		return nil
+	}
+
+	var (
+		refCommits []*Commit
+		parent     *list.Element
+	)
+	// collect all ref commits to add
+	commitIter := commitIterFunc(refCommit)
+	for c, e := commitIter.Next(); e == nil; {
+		parent, exists = commitsLookup[c.Hash]
+		if exists {
+			break
+		}
+		refCommits = append(refCommits, c)
+		c, e = commitIter.Next()
+	}
+	commitIter.Close()
+
+	if parent == nil {
+		// common parent - not found
+		// add all commits to the path from this ref (maybe it's a HEAD and we don't have anything, yet)
+		for _, c := range refCommits {
+			parent = commitsPath.PushBack(c)
+			commitsLookup[c.Hash] = parent
+		}
+	} else {
+		// add ref's commits to the path in reverse order (from the latest)
+		for i := len(refCommits) - 1; i >= 0; i-- {
+			c := refCommits[i]
+			// insert before found common parent
+			parent = commitsPath.InsertBefore(c, parent)
+			commitsLookup[c.Hash] = parent
+		}
+	}
+
+	return nil
+}
+
+func (it *commitAllIterator) Next() (*Commit, error) {
+	if it.currCommit == nil {
+		return nil, io.EOF
+	}
+
+	c := it.currCommit.Value.(*Commit)
+	it.currCommit = it.currCommit.Next()
+
+	return c, nil
+}
+
+func (it *commitAllIterator) ForEach(cb func(*Commit) error) error {
+	for {
+		c, err := it.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return err
+		}
+
+		err = cb(c)
+		if err == storer.ErrStop {
+			break
+		}
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (it *commitAllIterator) Close() {
+	it.currCommit = nil
+}
diff --git a/vendor/gopkg.in/src-d/go-git.v4/plumbing/object/commit_walker_file.go b/vendor/gopkg.in/src-d/go-git.v4/plumbing/object/commit_walker_file.go
index 84e738ac6c..6f16e611f1 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/plumbing/object/commit_walker_file.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/plumbing/object/commit_walker_file.go
@@ -1,23 +1,30 @@
 package object
 
 import (
-	"gopkg.in/src-d/go-git.v4/plumbing/storer"
 	"io"
+
+	"gopkg.in/src-d/go-git.v4/plumbing"
+
+	"gopkg.in/src-d/go-git.v4/plumbing/storer"
 )
 
 type commitFileIter struct {
 	fileName      string
 	sourceIter    CommitIter
 	currentCommit *Commit
+	checkParent   bool
 }
 
 // NewCommitFileIterFromIter returns a commit iterator which performs diffTree between
 // successive trees returned from the commit iterator from the argument. The purpose of this is
 // to find the commits that explain how the files that match the path came to be.
-func NewCommitFileIterFromIter(fileName string, commitIter CommitIter) CommitIter {
+// If checkParent is true then the function double checks if potential parent (next commit in a path)
+// is one of the parents in the tree (it's used by `git log --all`).
+func NewCommitFileIterFromIter(fileName string, commitIter CommitIter, checkParent bool) CommitIter {
 	iterator := new(commitFileIter)
 	iterator.sourceIter = commitIter
 	iterator.fileName = fileName
+	iterator.checkParent = checkParent
 	return iterator
 }
 
@@ -71,20 +78,14 @@ func (c *commitFileIter) getNextFileCommit() (*Commit, error) {
 			return nil, diffErr
 		}
 
-		foundChangeForFile := false
-		for _, change := range changes {
-			if change.name() == c.fileName {
-				foundChangeForFile = true
-				break
-			}
-		}
+		found := c.hasFileChange(changes, parentCommit)
 
 		// Storing the current-commit in-case a change is found, and
 		// Updating the current-commit for the next-iteration
 		prevCommit := c.currentCommit
 		c.currentCommit = parentCommit
 
-		if foundChangeForFile == true {
+		if found {
 			return prevCommit, nil
 		}
 
@@ -95,6 +96,35 @@ func (c *commitFileIter) getNextFileCommit() (*Commit, error) {
 	}
 }
 
+func (c *commitFileIter) hasFileChange(changes Changes, parent *Commit) bool {
+	for _, change := range changes {
+		if change.name() != c.fileName {
+			continue
+		}
+
+		// filename matches, now check if source iterator contains all commits (from all refs)
+		if c.checkParent {
+			if parent != nil && isParentHash(parent.Hash, c.currentCommit) {
+				return true
+			}
+			continue
+		}
+
+		return true
+	}
+
+	return false
+}
+
+func isParentHash(hash plumbing.Hash, commit *Commit) bool {
+	for _, h := range commit.ParentHashes {
+		if h == hash {
+			return true
+		}
+	}
+	return false
+}
+
 func (c *commitFileIter) ForEach(cb func(*Commit) error) error {
 	for {
 		commit, nextErr := c.Next()
diff --git a/vendor/gopkg.in/src-d/go-git.v4/plumbing/revlist/revlist.go b/vendor/gopkg.in/src-d/go-git.v4/plumbing/revlist/revlist.go
index 0a9d1e8120..7ad71ac044 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/plumbing/revlist/revlist.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/plumbing/revlist/revlist.go
@@ -21,7 +21,20 @@ func Objects(
 	objs,
 	ignore []plumbing.Hash,
 ) ([]plumbing.Hash, error) {
-	ignore, err := objects(s, ignore, nil, true)
+	return ObjectsWithStorageForIgnores(s, s, objs, ignore)
+}
+
+// ObjectsWithStorageForIgnores is the same as Objects, but a
+// secondary storage layer can be provided, to be used to finding the
+// full set of objects to be ignored while finding the reachable
+// objects.  This is useful when the main `s` storage layer is slow
+// and/or remote, while the ignore list is available somewhere local.
+func ObjectsWithStorageForIgnores(
+	s, ignoreStore storer.EncodedObjectStorer,
+	objs,
+	ignore []plumbing.Hash,
+) ([]plumbing.Hash, error) {
+	ignore, err := objects(ignoreStore, ignore, nil, true)
 	if err != nil {
 		return nil, err
 	}
@@ -114,7 +127,6 @@ func reachableObjects(
 	i := object.NewCommitPreorderIter(commit, seen, ignore)
 	pending := make(map[plumbing.Hash]bool)
 	addPendingParents(pending, visited, commit)
-
 	for {
 		commit, err := i.Next()
 		if err == io.EOF {
diff --git a/vendor/gopkg.in/src-d/go-git.v4/plumbing/storer/object.go b/vendor/gopkg.in/src-d/go-git.v4/plumbing/storer/object.go
index 2ac9b091ef..98d1ec3fec 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/plumbing/storer/object.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/plumbing/storer/object.go
@@ -222,7 +222,7 @@ type MultiEncodedObjectIter struct {
 }
 
 // NewMultiEncodedObjectIter returns an object iterator for the given slice of
-// objects.
+// EncodedObjectIters.
 func NewMultiEncodedObjectIter(iters []EncodedObjectIter) EncodedObjectIter {
 	return &MultiEncodedObjectIter{iters: iters}
 }
diff --git a/vendor/gopkg.in/src-d/go-git.v4/plumbing/storer/reference.go b/vendor/gopkg.in/src-d/go-git.v4/plumbing/storer/reference.go
index 5e85a3be4d..cce72b4aa3 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/plumbing/storer/reference.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/plumbing/storer/reference.go
@@ -131,9 +131,27 @@ func (iter *ReferenceSliceIter) Next() (*plumbing.Reference, error) {
 // an error happens or the end of the iter is reached. If ErrStop is sent
 // the iteration is stop but no error is returned. The iterator is closed.
 func (iter *ReferenceSliceIter) ForEach(cb func(*plumbing.Reference) error) error {
+	return forEachReferenceIter(iter, cb)
+}
+
+type bareReferenceIterator interface {
+	Next() (*plumbing.Reference, error)
+	Close()
+}
+
+func forEachReferenceIter(iter bareReferenceIterator, cb func(*plumbing.Reference) error) error {
 	defer iter.Close()
-	for _, r := range iter.series {
-		if err := cb(r); err != nil {
+	for {
+		obj, err := iter.Next()
+		if err != nil {
+			if err == io.EOF {
+				return nil
+			}
+
+			return err
+		}
+
+		if err := cb(obj); err != nil {
 			if err == ErrStop {
 				return nil
 			}
@@ -141,8 +159,6 @@ func (iter *ReferenceSliceIter) ForEach(cb func(*plumbing.Reference) error) erro
 			return err
 		}
 	}
-
-	return nil
 }
 
 // Close releases any resources used by the iterator.
@@ -150,6 +166,52 @@ func (iter *ReferenceSliceIter) Close() {
 	iter.pos = len(iter.series)
 }
 
+// MultiReferenceIter implements ReferenceIter. It iterates over several
+// ReferenceIter,
+//
+// The MultiReferenceIter must be closed with a call to Close() when it is no
+// longer needed.
+type MultiReferenceIter struct {
+	iters []ReferenceIter
+}
+
+// NewMultiReferenceIter returns an reference iterator for the given slice of
+// EncodedObjectIters.
+func NewMultiReferenceIter(iters []ReferenceIter) ReferenceIter {
+	return &MultiReferenceIter{iters: iters}
+}
+
+// Next returns the next reference from the iterator, if one iterator reach
+// io.EOF is removed and the next one is used.
+func (iter *MultiReferenceIter) Next() (*plumbing.Reference, error) {
+	if len(iter.iters) == 0 {
+		return nil, io.EOF
+	}
+
+	obj, err := iter.iters[0].Next()
+	if err == io.EOF {
+		iter.iters[0].Close()
+		iter.iters = iter.iters[1:]
+		return iter.Next()
+	}
+
+	return obj, err
+}
+
+// ForEach call the cb function for each reference contained on this iter until
+// an error happens or the end of the iter is reached. If ErrStop is sent
+// the iteration is stop but no error is returned. The iterator is closed.
+func (iter *MultiReferenceIter) ForEach(cb func(*plumbing.Reference) error) error {
+	return forEachReferenceIter(iter, cb)
+}
+
+// Close releases any resources used by the iterator.
+func (iter *MultiReferenceIter) Close() {
+	for _, i := range iter.iters {
+		i.Close()
+	}
+}
+
 // ResolveReference resolves a SymbolicReference to a HashReference.
 func ResolveReference(s ReferenceStorer, n plumbing.ReferenceName) (*plumbing.Reference, error) {
 	r, err := s.Reference(n)
diff --git a/vendor/gopkg.in/src-d/go-git.v4/plumbing/transport/common.go b/vendor/gopkg.in/src-d/go-git.v4/plumbing/transport/common.go
index f7b882b8b6..dcf9391d59 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/plumbing/transport/common.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/plumbing/transport/common.go
@@ -19,10 +19,10 @@ import (
 	"fmt"
 	"io"
 	"net/url"
-	"regexp"
 	"strconv"
 	"strings"
 
+	giturl "gopkg.in/src-d/go-git.v4/internal/url"
 	"gopkg.in/src-d/go-git.v4/plumbing"
 	"gopkg.in/src-d/go-git.v4/plumbing/protocol/packp"
 	"gopkg.in/src-d/go-git.v4/plumbing/protocol/packp/capability"
@@ -224,34 +224,28 @@ func getPath(u *url.URL) string {
 	return res
 }
 
-var (
-	isSchemeRegExp   = regexp.MustCompile(`^[^:]+://`)
-	scpLikeUrlRegExp = regexp.MustCompile(`^(?:(?P<user>[^@]+)@)?(?P<host>[^:\s]+):(?:(?P<port>[0-9]{1,5})/)?(?P<path>[^\\].*)$`)
-)
-
 func parseSCPLike(endpoint string) (*Endpoint, bool) {
-	if isSchemeRegExp.MatchString(endpoint) || !scpLikeUrlRegExp.MatchString(endpoint) {
+	if giturl.MatchesScheme(endpoint) || !giturl.MatchesScpLike(endpoint) {
 		return nil, false
 	}
 
-	m := scpLikeUrlRegExp.FindStringSubmatch(endpoint)
-
-	port, err := strconv.Atoi(m[3])
+	user, host, portStr, path := giturl.FindScpLikeComponents(endpoint)
+	port, err := strconv.Atoi(portStr)
 	if err != nil {
 		port = 22
 	}
 
 	return &Endpoint{
 		Protocol: "ssh",
-		User:     m[1],
-		Host:     m[2],
+		User:     user,
+		Host:     host,
 		Port:     port,
-		Path:     m[4],
+		Path:     path,
 	}, true
 }
 
 func parseFile(endpoint string) (*Endpoint, bool) {
-	if isSchemeRegExp.MatchString(endpoint) {
+	if giturl.MatchesScheme(endpoint) {
 		return nil, false
 	}
 
diff --git a/vendor/gopkg.in/src-d/go-git.v4/remote.go b/vendor/gopkg.in/src-d/go-git.v4/remote.go
index 8f4e41d725..de537ce8e8 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/remote.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/remote.go
@@ -6,8 +6,10 @@ import (
 	"fmt"
 	"io"
 
+	"gopkg.in/src-d/go-billy.v4/osfs"
 	"gopkg.in/src-d/go-git.v4/config"
 	"gopkg.in/src-d/go-git.v4/plumbing"
+	"gopkg.in/src-d/go-git.v4/plumbing/cache"
 	"gopkg.in/src-d/go-git.v4/plumbing/format/packfile"
 	"gopkg.in/src-d/go-git.v4/plumbing/object"
 	"gopkg.in/src-d/go-git.v4/plumbing/protocol/packp"
@@ -18,6 +20,7 @@ import (
 	"gopkg.in/src-d/go-git.v4/plumbing/transport"
 	"gopkg.in/src-d/go-git.v4/plumbing/transport/client"
 	"gopkg.in/src-d/go-git.v4/storage"
+	"gopkg.in/src-d/go-git.v4/storage/filesystem"
 	"gopkg.in/src-d/go-git.v4/storage/memory"
 	"gopkg.in/src-d/go-git.v4/utils/ioutil"
 )
@@ -149,7 +152,17 @@ func (r *Remote) PushContext(ctx context.Context, o *PushOptions) (err error) {
 	var hashesToPush []plumbing.Hash
 	// Avoid the expensive revlist operation if we're only doing deletes.
 	if !allDelete {
-		hashesToPush, err = revlist.Objects(r.s, objects, haves)
+		if r.c.IsFirstURLLocal() {
+			// If we're are pushing to a local repo, it might be much
+			// faster to use a local storage layer to get the commits
+			// to ignore, when calculating the object revlist.
+			localStorer := filesystem.NewStorage(
+				osfs.New(r.c.URLs[0]), cache.NewObjectLRUDefault())
+			hashesToPush, err = revlist.ObjectsWithStorageForIgnores(
+				r.s, localStorer, objects, haves)
+		} else {
+			hashesToPush, err = revlist.Objects(r.s, objects, haves)
+		}
 		if err != nil {
 			return err
 		}
diff --git a/vendor/gopkg.in/src-d/go-git.v4/repository.go b/vendor/gopkg.in/src-d/go-git.v4/repository.go
index f548e9a833..de92d64709 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/repository.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/repository.go
@@ -41,6 +41,8 @@ var (
 	ErrTagExists = errors.New("tag already exists")
 	// ErrTagNotFound an error stating the specified tag does not exist
 	ErrTagNotFound = errors.New("tag not found")
+	// ErrFetching is returned when the packfile could not be downloaded
+	ErrFetching = errors.New("unable to fetch packfile")
 
 	ErrInvalidReference          = errors.New("invalid reference, should be a tag or a branch")
 	ErrRepositoryNotExists       = errors.New("repository does not exist")
@@ -342,8 +344,9 @@ func PlainClone(path string, isBare bool, o *CloneOptions) (*Repository, error)
 // transport operations.
 //
 // TODO(mcuadros): move isBare to CloneOptions in v5
+// TODO(smola): refuse upfront to clone on a non-empty directory in v5, see #1027
 func PlainCloneContext(ctx context.Context, path string, isBare bool, o *CloneOptions) (*Repository, error) {
-	dirExists, err := checkExistsAndIsEmptyDir(path)
+	cleanup, cleanupParent, err := checkIfCleanupIsNeeded(path)
 	if err != nil {
 		return nil, err
 	}
@@ -355,7 +358,9 @@ func PlainCloneContext(ctx context.Context, path string, isBare bool, o *CloneOp
 
 	err = r.clone(ctx, o)
 	if err != nil && err != ErrRepositoryAlreadyExists {
-		cleanUpDir(path, !dirExists)
+		if cleanup {
+			cleanUpDir(path, cleanupParent)
+		}
 	}
 
 	return r, err
@@ -369,37 +374,37 @@ func newRepository(s storage.Storer, worktree billy.Filesystem) *Repository {
 	}
 }
 
-func checkExistsAndIsEmptyDir(path string) (exists bool, err error) {
+func checkIfCleanupIsNeeded(path string) (cleanup bool, cleanParent bool, err error) {
 	fi, err := os.Stat(path)
 	if err != nil {
 		if os.IsNotExist(err) {
-			return false, nil
+			return true, true, nil
 		}
 
-		return false, err
+		return false, false, err
 	}
 
 	if !fi.IsDir() {
-		return false, fmt.Errorf("path is not a directory: %s", path)
+		return false, false, fmt.Errorf("path is not a directory: %s", path)
 	}
 
 	f, err := os.Open(path)
 	if err != nil {
-		return false, err
+		return false, false, err
 	}
 
 	defer ioutil.CheckClose(f, &err)
 
 	_, err = f.Readdirnames(1)
 	if err == io.EOF {
-		return true, nil
+		return true, false, nil
 	}
 
 	if err != nil {
-		return true, err
+		return false, false, err
 	}
 
-	return true, fmt.Errorf("directory is not empty: %s", path)
+	return false, false, nil
 }
 
 func cleanUpDir(path string, all bool) error {
@@ -425,7 +430,7 @@ func cleanUpDir(path string, all bool) error {
 		}
 	}
 
-	return nil
+	return err
 }
 
 // Config return the repository config
@@ -855,6 +860,8 @@ func (r *Repository) fetchAndUpdateReferences(
 	remoteRefs, err := remote.fetch(ctx, o)
 	if err == NoErrAlreadyUpToDate {
 		objsUpdated = false
+	} else if err == packfile.ErrEmptyPackfile {
+		return nil, ErrFetching
 	} else if err != nil {
 		return nil, err
 	}
@@ -1020,8 +1027,36 @@ func (r *Repository) PushContext(ctx context.Context, o *PushOptions) error {
 
 // Log returns the commit history from the given LogOptions.
 func (r *Repository) Log(o *LogOptions) (object.CommitIter, error) {
-	h := o.From
-	if o.From == plumbing.ZeroHash {
+	fn := commitIterFunc(o.Order)
+	if fn == nil {
+		return nil, fmt.Errorf("invalid Order=%v", o.Order)
+	}
+
+	var (
+		it  object.CommitIter
+		err error
+	)
+	if o.All {
+		it, err = r.logAll(fn)
+	} else {
+		it, err = r.log(o.From, fn)
+	}
+
+	if err != nil {
+		return nil, err
+	}
+
+	if o.FileName != nil {
+		// for `git log --all` also check parent (if the next commit comes from the real parent)
+		it = r.logWithFile(*o.FileName, it, o.All)
+	}
+
+	return it, nil
+}
+
+func (r *Repository) log(from plumbing.Hash, commitIterFunc func(*object.Commit) object.CommitIter) (object.CommitIter, error) {
+	h := from
+	if from == plumbing.ZeroHash {
 		head, err := r.Head()
 		if err != nil {
 			return nil, err
@@ -1034,27 +1069,41 @@ func (r *Repository) Log(o *LogOptions) (object.CommitIter, error) {
 	if err != nil {
 		return nil, err
 	}
+	return commitIterFunc(commit), nil
+}
+
+func (r *Repository) logAll(commitIterFunc func(*object.Commit) object.CommitIter) (object.CommitIter, error) {
+	return object.NewCommitAllIter(r.Storer, commitIterFunc)
+}
 
-	var commitIter object.CommitIter
-	switch o.Order {
+func (*Repository) logWithFile(fileName string, commitIter object.CommitIter, checkParent bool) object.CommitIter {
+	return object.NewCommitFileIterFromIter(fileName, commitIter, checkParent)
+}
+
+func commitIterFunc(order LogOrder) func(c *object.Commit) object.CommitIter {
+	switch order {
 	case LogOrderDefault:
-		commitIter = object.NewCommitPreorderIter(commit, nil, nil)
+		return func(c *object.Commit) object.CommitIter {
+			return object.NewCommitPreorderIter(c, nil, nil)
+		}
 	case LogOrderDFS:
-		commitIter = object.NewCommitPreorderIter(commit, nil, nil)
+		return func(c *object.Commit) object.CommitIter {
+			return object.NewCommitPreorderIter(c, nil, nil)
+		}
 	case LogOrderDFSPost:
-		commitIter = object.NewCommitPostorderIter(commit, nil)
+		return func(c *object.Commit) object.CommitIter {
+			return object.NewCommitPostorderIter(c, nil)
+		}
 	case LogOrderBSF:
-		commitIter = object.NewCommitIterBSF(commit, nil, nil)
+		return func(c *object.Commit) object.CommitIter {
+			return object.NewCommitIterBSF(c, nil, nil)
+		}
 	case LogOrderCommitterTime:
-		commitIter = object.NewCommitIterCTime(commit, nil, nil)
-	default:
-		return nil, fmt.Errorf("invalid Order=%v", o.Order)
-	}
-
-	if o.FileName == nil {
-		return commitIter, nil
+		return func(c *object.Commit) object.CommitIter {
+			return object.NewCommitIterCTime(c, nil, nil)
+		}
 	}
-	return object.NewCommitFileIterFromIter(*o.FileName, commitIter), nil
+	return nil
 }
 
 // Tags returns all the tag References in a repository.
diff --git a/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/dotgit/dotgit.go b/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/dotgit/dotgit.go
index a58c2482a2..ba9667e65e 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/dotgit/dotgit.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/dotgit/dotgit.go
@@ -14,6 +14,7 @@ import (
 
 	"gopkg.in/src-d/go-billy.v4/osfs"
 	"gopkg.in/src-d/go-git.v4/plumbing"
+	"gopkg.in/src-d/go-git.v4/storage"
 	"gopkg.in/src-d/go-git.v4/utils/ioutil"
 
 	"gopkg.in/src-d/go-billy.v4"
@@ -596,7 +597,7 @@ func (d *DotGit) checkReferenceAndTruncate(f billy.File, old *plumbing.Reference
 		return err
 	}
 	if ref.Hash() != old.Hash() {
-		return fmt.Errorf("reference has changed concurrently")
+		return storage.ErrReferenceHasChanged
 	}
 	_, err = f.Seek(0, io.SeekStart)
 	if err != nil {
diff --git a/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/dotgit/dotgit_setref.go b/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/dotgit/dotgit_setref.go
index d27c1a3039..9da2f31e89 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/dotgit/dotgit_setref.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/dotgit/dotgit_setref.go
@@ -1,15 +1,24 @@
-// +build !norwfs
-
 package dotgit
 
 import (
+	"fmt"
 	"os"
 
 	"gopkg.in/src-d/go-git.v4/plumbing"
 	"gopkg.in/src-d/go-git.v4/utils/ioutil"
+
+	"gopkg.in/src-d/go-billy.v4"
 )
 
 func (d *DotGit) setRef(fileName, content string, old *plumbing.Reference) (err error) {
+	if billy.CapabilityCheck(d.fs, billy.ReadAndWriteCapability) {
+		return d.setRefRwfs(fileName, content, old)
+	}
+
+	return d.setRefNorwfs(fileName, content, old)
+}
+
+func (d *DotGit) setRefRwfs(fileName, content string, old *plumbing.Reference) (err error) {
 	// If we are not checking an old ref, just truncate the file.
 	mode := os.O_RDWR | os.O_CREATE
 	if old == nil {
@@ -41,3 +50,41 @@ func (d *DotGit) setRef(fileName, content string, old *plumbing.Reference) (err
 	_, err = f.Write([]byte(content))
 	return err
 }
+
+// There are some filesystems that don't support opening files in RDWD mode.
+// In these filesystems the standard SetRef function can not be used as it
+// reads the reference file to check that it's not modified before updating it.
+//
+// This version of the function writes the reference without extra checks
+// making it compatible with these simple filesystems. This is usually not
+// a problem as they should be accessed by only one process at a time.
+func (d *DotGit) setRefNorwfs(fileName, content string, old *plumbing.Reference) error {
+	_, err := d.fs.Stat(fileName)
+	if err == nil && old != nil {
+		fRead, err := d.fs.Open(fileName)
+		if err != nil {
+			return err
+		}
+
+		ref, err := d.readReferenceFrom(fRead, old.Name().String())
+		fRead.Close()
+
+		if err != nil {
+			return err
+		}
+
+		if ref.Hash() != old.Hash() {
+			return fmt.Errorf("reference has changed concurrently")
+		}
+	}
+
+	f, err := d.fs.Create(fileName)
+	if err != nil {
+		return err
+	}
+
+	defer f.Close()
+
+	_, err = f.Write([]byte(content))
+	return err
+}
diff --git a/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/dotgit/dotgit_setref_norwfs.go b/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/dotgit/dotgit_setref_norwfs.go
deleted file mode 100644
index 5695bd3b61..0000000000
--- a/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/dotgit/dotgit_setref_norwfs.go
+++ /dev/null
@@ -1,47 +0,0 @@
-// +build norwfs
-
-package dotgit
-
-import (
-	"fmt"
-
-	"gopkg.in/src-d/go-git.v4/plumbing"
-)
-
-// There are some filesystems that don't support opening files in RDWD mode.
-// In these filesystems the standard SetRef function can not be used as i
-// reads the reference file to check that it's not modified before updating it.
-//
-// This version of the function writes the reference without extra checks
-// making it compatible with these simple filesystems. This is usually not
-// a problem as they should be accessed by only one process at a time.
-func (d *DotGit) setRef(fileName, content string, old *plumbing.Reference) error {
-	_, err := d.fs.Stat(fileName)
-	if err == nil && old != nil {
-		fRead, err := d.fs.Open(fileName)
-		if err != nil {
-			return err
-		}
-
-		ref, err := d.readReferenceFrom(fRead, old.Name().String())
-		fRead.Close()
-
-		if err != nil {
-			return err
-		}
-
-		if ref.Hash() != old.Hash() {
-			return fmt.Errorf("reference has changed concurrently")
-		}
-	}
-
-	f, err := d.fs.Create(fileName)
-	if err != nil {
-		return err
-	}
-
-	defer f.Close()
-
-	_, err = f.Write([]byte(content))
-	return err
-}
diff --git a/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/object.go b/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/object.go
index 57dcbb43f9..3eb62a22f4 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/object.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/object.go
@@ -20,24 +20,25 @@ import (
 type ObjectStorage struct {
 	options Options
 
-	// deltaBaseCache is an object cache uses to cache delta's bases when
-	deltaBaseCache cache.Object
+	// objectCache is an object cache uses to cache delta's bases and also recently
+	// loaded loose objects
+	objectCache cache.Object
 
 	dir   *dotgit.DotGit
 	index map[plumbing.Hash]idxfile.Index
 }
 
 // NewObjectStorage creates a new ObjectStorage with the given .git directory and cache.
-func NewObjectStorage(dir *dotgit.DotGit, cache cache.Object) *ObjectStorage {
-	return NewObjectStorageWithOptions(dir, cache, Options{})
+func NewObjectStorage(dir *dotgit.DotGit, objectCache cache.Object) *ObjectStorage {
+	return NewObjectStorageWithOptions(dir, objectCache, Options{})
 }
 
 // NewObjectStorageWithOptions creates a new ObjectStorage with the given .git directory, cache and extra options
-func NewObjectStorageWithOptions(dir *dotgit.DotGit, cache cache.Object, ops Options) *ObjectStorage {
+func NewObjectStorageWithOptions(dir *dotgit.DotGit, objectCache cache.Object, ops Options) *ObjectStorage {
 	return &ObjectStorage{
-		options:        ops,
-		deltaBaseCache: cache,
-		dir:            dir,
+		options:     ops,
+		objectCache: objectCache,
+		dir:         dir,
 	}
 }
 
@@ -206,7 +207,7 @@ func (s *ObjectStorage) encodedObjectSizeFromPackfile(h plumbing.Hash) (
 	idx := s.index[pack]
 	hash, err := idx.FindHash(offset)
 	if err == nil {
-		obj, ok := s.deltaBaseCache.Get(hash)
+		obj, ok := s.objectCache.Get(hash)
 		if ok {
 			return obj.Size(), nil
 		}
@@ -215,8 +216,8 @@ func (s *ObjectStorage) encodedObjectSizeFromPackfile(h plumbing.Hash) (
 	}
 
 	var p *packfile.Packfile
-	if s.deltaBaseCache != nil {
-		p = packfile.NewPackfileWithCache(idx, s.dir.Fs(), f, s.deltaBaseCache)
+	if s.objectCache != nil {
+		p = packfile.NewPackfileWithCache(idx, s.dir.Fs(), f, s.objectCache)
 	} else {
 		p = packfile.NewPackfile(idx, s.dir.Fs(), f)
 	}
@@ -241,9 +242,19 @@ func (s *ObjectStorage) EncodedObjectSize(h plumbing.Hash) (
 // EncodedObject returns the object with the given hash, by searching for it in
 // the packfile and the git object directories.
 func (s *ObjectStorage) EncodedObject(t plumbing.ObjectType, h plumbing.Hash) (plumbing.EncodedObject, error) {
-	obj, err := s.getFromUnpacked(h)
-	if err == plumbing.ErrObjectNotFound {
+	var obj plumbing.EncodedObject
+	var err error
+
+	if s.index != nil {
 		obj, err = s.getFromPackfile(h, false)
+		if err == plumbing.ErrObjectNotFound {
+			obj, err = s.getFromUnpacked(h)
+		}
+	} else {
+		obj, err = s.getFromUnpacked(h)
+		if err == plumbing.ErrObjectNotFound {
+			obj, err = s.getFromPackfile(h, false)
+		}
 	}
 
 	// If the error is still object not found, check if it's a shared object
@@ -254,7 +265,7 @@ func (s *ObjectStorage) EncodedObject(t plumbing.ObjectType, h plumbing.Hash) (p
 			// Create a new object storage with the DotGit(s) and check for the
 			// required hash object. Skip when not found.
 			for _, dg := range dotgits {
-				o := NewObjectStorage(dg, s.deltaBaseCache)
+				o := NewObjectStorage(dg, s.objectCache)
 				enobj, enerr := o.EncodedObject(t, h)
 				if enerr != nil {
 					continue
@@ -304,9 +315,12 @@ func (s *ObjectStorage) getFromUnpacked(h plumbing.Hash) (obj plumbing.EncodedOb
 
 		return nil, err
 	}
-
 	defer ioutil.CheckClose(f, &err)
 
+	if cacheObj, found := s.objectCache.Get(h); found {
+		return cacheObj, nil
+	}
+
 	obj = s.NewEncodedObject()
 	r, err := objfile.NewReader(f)
 	if err != nil {
@@ -327,6 +341,8 @@ func (s *ObjectStorage) getFromUnpacked(h plumbing.Hash) (obj plumbing.EncodedOb
 		return nil, err
 	}
 
+	s.objectCache.Put(obj)
+
 	_, err = io.Copy(w, r)
 	return obj, err
 }
@@ -369,7 +385,7 @@ func (s *ObjectStorage) decodeObjectAt(
 ) (plumbing.EncodedObject, error) {
 	hash, err := idx.FindHash(offset)
 	if err == nil {
-		obj, ok := s.deltaBaseCache.Get(hash)
+		obj, ok := s.objectCache.Get(hash)
 		if ok {
 			return obj, nil
 		}
@@ -380,8 +396,8 @@ func (s *ObjectStorage) decodeObjectAt(
 	}
 
 	var p *packfile.Packfile
-	if s.deltaBaseCache != nil {
-		p = packfile.NewPackfileWithCache(idx, s.dir.Fs(), f, s.deltaBaseCache)
+	if s.objectCache != nil {
+		p = packfile.NewPackfileWithCache(idx, s.dir.Fs(), f, s.objectCache)
 	} else {
 		p = packfile.NewPackfile(idx, s.dir.Fs(), f)
 	}
@@ -400,11 +416,7 @@ func (s *ObjectStorage) decodeDeltaObjectAt(
 	}
 
 	p := packfile.NewScanner(f)
-	if _, err := p.SeekFromStart(offset); err != nil {
-		return nil, err
-	}
-
-	header, err := p.NextObjectHeader()
+	header, err := p.SeekObjectHeader(offset)
 	if err != nil {
 		return nil, err
 	}
@@ -495,7 +507,7 @@ func (s *ObjectStorage) buildPackfileIters(
 			}
 			return newPackfileIter(
 				s.dir.Fs(), pack, t, seen, s.index[h],
-				s.deltaBaseCache, s.options.KeepDescriptors,
+				s.objectCache, s.options.KeepDescriptors,
 			)
 		},
 	}, nil
diff --git a/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/storage.go b/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/storage.go
index 14a772abe0..370f7bd34a 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/storage.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/storage/filesystem/storage.go
@@ -51,11 +51,7 @@ func NewStorageWithOptions(fs billy.Filesystem, cache cache.Object, ops Options)
 		fs:  fs,
 		dir: dir,
 
-		ObjectStorage: ObjectStorage{
-			options:        ops,
-			deltaBaseCache: cache,
-			dir:            dir,
-		},
+		ObjectStorage:    *NewObjectStorageWithOptions(dir, cache, ops),
 		ReferenceStorage: ReferenceStorage{dir: dir},
 		IndexStorage:     IndexStorage{dir: dir},
 		ShallowStorage:   ShallowStorage{dir: dir},
diff --git a/vendor/gopkg.in/src-d/go-git.v4/storage/memory/storage.go b/vendor/gopkg.in/src-d/go-git.v4/storage/memory/storage.go
index 6e1174240f..f240f2a1f9 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/storage/memory/storage.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/storage/memory/storage.go
@@ -13,7 +13,6 @@ import (
 )
 
 var ErrUnsupportedObjectType = fmt.Errorf("unsupported object type")
-var ErrRefHasChanged = fmt.Errorf("reference has changed concurrently")
 
 // Storage is an implementation of git.Storer that stores data on memory, being
 // ephemeral. The use of this storage should be done in controlled envoriments,
@@ -258,7 +257,7 @@ func (r ReferenceStorage) CheckAndSetReference(ref, old *plumbing.Reference) err
 	if old != nil {
 		tmp := r[ref.Name()]
 		if tmp != nil && tmp.Hash() != old.Hash() {
-			return ErrRefHasChanged
+			return storage.ErrReferenceHasChanged
 		}
 	}
 	r[ref.Name()] = ref
diff --git a/vendor/gopkg.in/src-d/go-git.v4/storage/storer.go b/vendor/gopkg.in/src-d/go-git.v4/storage/storer.go
index d1a94f2a7c..5de0cfb96c 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/storage/storer.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/storage/storer.go
@@ -1,10 +1,14 @@
 package storage
 
 import (
+	"errors"
+
 	"gopkg.in/src-d/go-git.v4/config"
 	"gopkg.in/src-d/go-git.v4/plumbing/storer"
 )
 
+var ErrReferenceHasChanged = errors.New("reference has changed concurrently")
+
 // Storer is a generic storage of objects, references and any information
 // related to a particular repository. The package gopkg.in/src-d/go-git.v4/storage
 // contains two implementation a filesystem base implementation (such as `.git`)
diff --git a/vendor/gopkg.in/src-d/go-git.v4/utils/merkletrie/noder/path.go b/vendor/gopkg.in/src-d/go-git.v4/utils/merkletrie/noder/path.go
index e9c905c96b..1c7ef54eeb 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/utils/merkletrie/noder/path.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/utils/merkletrie/noder/path.go
@@ -3,8 +3,6 @@ package noder
 import (
 	"bytes"
 	"strings"
-
-	"golang.org/x/text/unicode/norm"
 )
 
 // Path values represent a noder and its ancestors.  The root goes first
@@ -80,11 +78,9 @@ func (p Path) Compare(other Path) int {
 		case i == len(p):
 			return -1
 		default:
-			form := norm.Form(norm.NFC)
-			this := form.String(p[i].Name())
-			that := form.String(other[i].Name())
-
-			cmp := strings.Compare(this, that)
+			// We do *not* normalize Unicode here. CGit doesn't.
+			// https://github.com/src-d/go-git/issues/1057
+			cmp := strings.Compare(p[i].Name(), other[i].Name())
 			if cmp != 0 {
 				return cmp
 			}
diff --git a/vendor/gopkg.in/src-d/go-git.v4/worktree.go b/vendor/gopkg.in/src-d/go-git.v4/worktree.go
index e45d815484..a14fd8d6c3 100644
--- a/vendor/gopkg.in/src-d/go-git.v4/worktree.go
+++ b/vendor/gopkg.in/src-d/go-git.v4/worktree.go
@@ -25,10 +25,11 @@ import (
 )
 
 var (
-	ErrWorktreeNotClean  = errors.New("worktree is not clean")
-	ErrSubmoduleNotFound = errors.New("submodule not found")
-	ErrUnstagedChanges   = errors.New("worktree contains unstaged changes")
-	ErrGitModulesSymlink = errors.New(gitmodulesFile + " is a symlink")
+	ErrWorktreeNotClean     = errors.New("worktree is not clean")
+	ErrSubmoduleNotFound    = errors.New("submodule not found")
+	ErrUnstagedChanges      = errors.New("worktree contains unstaged changes")
+	ErrGitModulesSymlink    = errors.New(gitmodulesFile + " is a symlink")
+	ErrNonFastForwardUpdate = errors.New("non-fast-forward update")
 )
 
 // Worktree represents a git worktree.
@@ -101,7 +102,7 @@ func (w *Worktree) PullContext(ctx context.Context, o *PullOptions) error {
 		}
 
 		if !ff {
-			return fmt.Errorf("non-fast-forward update")
+			return ErrNonFastForwardUpdate
 		}
 	}
 
diff --git a/vendor/modules.txt b/vendor/modules.txt
index 899965af4e..929353e3e6 100644
--- a/vendor/modules.txt
+++ b/vendor/modules.txt
@@ -415,7 +415,7 @@ gopkg.in/src-d/go-billy.v4/osfs
 gopkg.in/src-d/go-billy.v4/util
 gopkg.in/src-d/go-billy.v4/helper/chroot
 gopkg.in/src-d/go-billy.v4/helper/polyfill
-# gopkg.in/src-d/go-git.v4 v4.8.0
+# gopkg.in/src-d/go-git.v4 v4.10.0
 gopkg.in/src-d/go-git.v4
 gopkg.in/src-d/go-git.v4/config
 gopkg.in/src-d/go-git.v4/plumbing
@@ -442,6 +442,7 @@ gopkg.in/src-d/go-git.v4/utils/merkletrie
 gopkg.in/src-d/go-git.v4/utils/merkletrie/filesystem
 gopkg.in/src-d/go-git.v4/utils/merkletrie/index
 gopkg.in/src-d/go-git.v4/utils/merkletrie/noder
+gopkg.in/src-d/go-git.v4/internal/url
 gopkg.in/src-d/go-git.v4/plumbing/format/config
 gopkg.in/src-d/go-git.v4/utils/binary
 gopkg.in/src-d/go-git.v4/plumbing/format/idxfile