mox!

vendor/github.com/mjl-/bstore/equal.go

@@ -0,0 +1,91 @@
+package bstore
+
+import (
+	"bytes"
+	"encoding"
+	"reflect"
+	"time"
+)
+
+// equal checks if ov and v are the same as far as storage is concerned. i.e.
+// this only takes stored fields into account. reflect.DeepEqual cannot be used,
+// it would take all fields into account, including unexported.
+func (tv *typeVersion) equal(ov, v reflect.Value) (r bool) {
+	if !ov.IsValid() || !v.IsValid() {
+		return false
+	}
+	for _, f := range tv.Fields {
+		fov := ov.FieldByIndex(f.structField.Index)
+		fv := v.FieldByIndex(f.structField.Index)
+		if !f.Type.equal(fov, fv) {
+			return false
+		}
+	}
+	return true
+}
+
+func (ft fieldType) equal(ov, v reflect.Value) (r bool) {
+	if ov == v {
+		return true
+	} else if !ov.IsValid() || !v.IsValid() {
+		return false
+	}
+	if ft.Ptr {
+		ov = ov.Elem()
+		v = v.Elem()
+	}
+	if ov == v {
+		return true
+	} else if !ov.IsValid() || !v.IsValid() {
+		return false
+	}
+	switch ft.Kind {
+	case kindBytes:
+		return bytes.Equal(ov.Bytes(), v.Bytes())
+	case kindMap:
+		on := ov.Len()
+		n := v.Len()
+		if on != n {
+			return false
+		}
+		r := ov.MapRange()
+		for r.Next() {
+			vv := v.MapIndex(r.Key())
+			if !vv.IsValid() || !ft.MapValue.equal(r.Value(), vv) {
+				return false
+			}
+		}
+		return true
+	case kindSlice:
+		on := ov.Len()
+		n := v.Len()
+		if on != n {
+			return false
+		}
+		for i := 0; i < n; i++ {
+			if !ft.List.equal(ov.Index(i), v.Index(i)) {
+				return false
+			}
+		}
+		return true
+	case kindTime:
+		return ov.Interface().(time.Time).Equal(v.Interface().(time.Time))
+	case kindBinaryMarshal:
+		obuf, oerr := ov.Interface().(encoding.BinaryMarshaler).MarshalBinary()
+		buf, err := v.Interface().(encoding.BinaryMarshaler).MarshalBinary()
+		if oerr != nil || err != nil {
+			return false // todo: should propagate error?
+		}
+		return bytes.Equal(obuf, buf)
+	case kindStruct:
+		for _, f := range ft.Fields {
+			fov := ov.FieldByIndex(f.structField.Index)
+			fv := v.FieldByIndex(f.structField.Index)
+			if !f.Type.equal(fov, fv) {
+				return false
+			}
+		}
+		return true
+	}
+	return ov.Interface() == v.Interface()
+}