move lib/go/gremlin to ent/dialect (#1192)

Summary:
Pull Request resolved: https://github.com/facebookexternal/fbc/pull/1192

Pull Request resolved: https://github.com/facebookincubator/ent/pull/11

Reviewed By: alexsn

Differential Revision: D16377224

fbshipit-source-id: 07ca7436eb9b64fbe2299568560b91466b2417ba

dialect/gremlin/encoding/graphson/time.go

@@ -0,0 +1,30 @@
+package graphson
+
+import (
+	"time"
+	"unsafe"
+
+	"github.com/json-iterator/go"
+)
+
+func init() {
+	RegisterTypeEncoder("time.Time", typeEncoder{timeCodec{}, Timestamp})
+	RegisterTypeDecoder("time.Time", typeDecoder{timeCodec{}, Types{Timestamp, Date}})
+}
+
+type timeCodec struct{}
+
+func (timeCodec) IsEmpty(ptr unsafe.Pointer) bool {
+	ts := *((*time.Time)(ptr))
+	return ts.IsZero()
+}
+
+func (timeCodec) Encode(ptr unsafe.Pointer, stream *jsoniter.Stream) {
+	ts := *((*time.Time)(ptr))
+	stream.WriteInt64(ts.UnixNano() / time.Millisecond.Nanoseconds())
+}
+
+func (timeCodec) Decode(ptr unsafe.Pointer, iter *jsoniter.Iterator) {
+	ns := iter.ReadInt64() * time.Millisecond.Nanoseconds()
+	*((*time.Time)(ptr)) = time.Unix(0, ns)
+}