diff --git a/spew/common.go b/spew/common.go
index 11b6d56..3a3a2b0 100644
--- a/spew/common.go
+++ b/spew/common.go
@@ -20,6 +20,7 @@ import (
 	"fmt"
 	"io"
 	"reflect"
+	"sort"
 	"strconv"
 	"unsafe"
 )
@@ -249,3 +250,51 @@ func printHexPtr(w io.Writer, p uintptr) {
 	buf = buf[i:]
 	w.Write(buf)
 }
+
+// valuesSorter implements sort.Interface to allow a slice of reflect.Value
+// elements to be sorted.
+type valuesSorter struct {
+	values []reflect.Value
+}
+
+// Len returns the number of values in the slice.  It is part of the
+// sort.Interface implementation.
+func (s *valuesSorter) Len() int {
+	return len(s.values)
+}
+
+// Swap swaps the values at the passed indices.  It is part of the
+// sort.Interface implementation.
+func (s *valuesSorter) Swap(i, j int) {
+	s.values[i], s.values[j] = s.values[j], s.values[i]
+}
+
+// Less returns whether the value at index i should sort before the
+// value at index j.  It is part of the sort.Interface implementation.
+func (s *valuesSorter) Less(i, j int) bool {
+	switch s.values[i].Kind() {
+	case reflect.Bool:
+		return !s.values[i].Bool() && s.values[j].Bool()
+	case reflect.Float32, reflect.Float64:
+		return s.values[i].Float() < s.values[j].Float()
+	case reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Int:
+		return s.values[i].Int() < s.values[j].Int()
+	case reflect.String:
+		return s.values[i].String() < s.values[j].String()
+	case reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uint:
+		return s.values[i].Uint() < s.values[j].Uint()
+	case reflect.Uintptr:
+		return s.values[i].UnsafeAddr() < s.values[j].UnsafeAddr()
+	}
+	return s.values[i].String() < s.values[j].String()
+}
+
+// sortValues is a generic sort function for native types: int, uint, bool,
+// string and uintptr.  Other inputs are sorted according to their
+// Value.String() value to ensure display stability.
+func sortValues(values []reflect.Value) {
+	if len(values) == 0 {
+		return
+	}
+	sort.Sort(&valuesSorter{values})
+}
diff --git a/spew/dump.go b/spew/dump.go
index b5dcfb2..3d57306 100644
--- a/spew/dump.go
+++ b/spew/dump.go
@@ -24,7 +24,6 @@ import (
 	"os"
 	"reflect"
 	"regexp"
-	"sort"
 	"strconv"
 	"strings"
 )
@@ -242,46 +241,6 @@ func (d *dumpState) dumpSlice(v reflect.Value) {
 	}
 }
 
-type valuesSorter struct {
-	values []reflect.Value
-}
-
-func (s *valuesSorter) Len() int {
-	return len(s.values)
-}
-
-func (s *valuesSorter) Swap(i, j int) {
-	s.values[i], s.values[j] = s.values[j], s.values[i]
-}
-
-func (s *valuesSorter) Less(i, j int) bool {
-	switch s.values[i].Kind() {
-	case reflect.Bool:
-		return !s.values[i].Bool() && s.values[j].Bool()
-	case reflect.Float32, reflect.Float64:
-		return s.values[i].Float() < s.values[j].Float()
-	case reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Int:
-		return s.values[i].Int() < s.values[j].Int()
-	case reflect.String:
-		return s.values[i].String() < s.values[j].String()
-	case reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uint:
-		return s.values[i].Uint() < s.values[j].Uint()
-	case reflect.Uintptr:
-		return s.values[i].UnsafeAddr() < s.values[j].UnsafeAddr()
-	}
-	return s.values[i].String() < s.values[j].String()
-}
-
-// SortValues is a generic sort function for native types: int, uint, bool,
-// string and uintptr.  Other inputs are sorted according to their
-// Value.String() value to ensure display stability.
-func SortValues(values []reflect.Value) {
-	if len(values) == 0 {
-		return
-	}
-	sort.Sort(&valuesSorter{values})
-}
-
 // dump is the main workhorse for dumping a value.  It uses the passed reflect
 // value to figure out what kind of object we are dealing with and formats it
 // appropriately.  It is a recursive function, however circular data structures
@@ -391,7 +350,7 @@ func (d *dumpState) dump(v reflect.Value) {
 			numEntries := v.Len()
 			keys := v.MapKeys()
 			if d.cs.SortKeys {
-				SortValues(keys)
+				sortValues(keys)
 			}
 			for i, key := range keys {
 				d.dump(d.unpackValue(key))
diff --git a/spew/format.go b/spew/format.go
index fc57fda..b6b1fb0 100644
--- a/spew/format.go
+++ b/spew/format.go
@@ -303,7 +303,7 @@ func (f *formatState) format(v reflect.Value) {
 		} else {
 			keys := v.MapKeys()
 			if f.cs.SortKeys {
-				SortValues(keys)
+				sortValues(keys)
 			}
 			for i, key := range keys {
 				if i > 0 {
diff --git a/spew/internal_test.go b/spew/internal_test.go
index 05bab97..d8c9761 100644
--- a/spew/internal_test.go
+++ b/spew/internal_test.go
@@ -155,3 +155,9 @@ func TestAddedReflectValue(t *testing.T) {
 		t.Errorf("TestAddedReflectValue #%d got: %s want: %s", i, s, want)
 	}
 }
+
+// SortValues makes the internal sortValues function available to the test
+// package.
+func SortValues(values []reflect.Value) {
+	sortValues(values)
+}