4 files changed, 12 insertions, 6 deletions
diff --git a/formats/packfile/reader.go b/formats/packfile/reader.go
index a013776..3f7081b 100644
--- a/formats/packfile/reader.go
+++ b/formats/packfile/reader.go
@@ -22,7 +22,7 @@ var (
 	InvalidObjectErr          = newError("invalid git object")
 	PatchingErr               = newError("patching error")
 	PackEntryNotFoundErr      = newError("can't find a pack entry")
-	ObjectNotFoundErr         = newError("can't find a object")
+	ErrObjectNotFound         = newError("can't find a object")
 	ZLibErr                   = newError("zlib reading error")
 )
 
@@ -200,8 +200,8 @@ func (r *Reader) readREFDelta(raw core.Object) (err error) {
 
 	referenced, err := r.s.Get(ref)
 	if err != nil {
-		if err == core.ObjectNotFoundErr {
-			return ObjectNotFoundErr.n("%s", ref)
+		if err == core.ErrObjectNotFound {
+			return ErrObjectNotFound.n("%s", ref)
 		}
 		return err
 	}
diff --git a/formats/pktline/decoder.go b/formats/pktline/decoder.go
index c30be6b..34e6f51 100644
--- a/formats/pktline/decoder.go
+++ b/formats/pktline/decoder.go
@@ -7,9 +7,12 @@ import (
 )
 
 var (
-	ErrUnderflow     = errors.New("unexpected string length (underflow)")
+	// ErrUnderflow is triggered when a line is shorter than the described length
+	ErrUnderflow = errors.New("unexpected string length (underflow)")
+	// ErrInvalidHeader invalid pktline header
 	ErrInvalidHeader = errors.New("invalid header")
-	ErrInvalidLen    = errors.New("invalid length")
+	// ErrInvalidLen ivanlid line length found, < 0
+	ErrInvalidLen = errors.New("invalid length")
 )
 
 // Decoder implements a pkt-line format decoder
diff --git a/formats/pktline/doc.go b/formats/pktline/doc.go
index 0ae22e3..555a073 100644
--- a/formats/pktline/doc.go
+++ b/formats/pktline/doc.go
@@ -51,6 +51,8 @@ package pktline
 // https://github.com/git/git/blob/master/Documentation/technical/protocol-common.txt
 
 const (
+	// HeaderLength length of the pktline header
 	HeaderLength = 4
-	MaxLength    = 65524
+	// MaxLength max line length
+	MaxLength = 65524
 )
diff --git a/formats/pktline/encoder.go b/formats/pktline/encoder.go
index dfa53e2..bd0ab75 100644
--- a/formats/pktline/encoder.go
+++ b/formats/pktline/encoder.go
@@ -7,6 +7,7 @@ import (
 )
 
 var (
+	//ErrOverflow happends when the line length exceed the MaxLength
 	ErrOverflow = errors.New("unexpected string length (overflow)")
 )