Added Map.Keys() method

Author: cmaglie

properties.go

@@ -287,6 +287,17 @@ func (m Map) Merge(sources ...Map) Map {
 	return m
 }
 
+// Keys returns an array of the keys contained in the Map
+func (m Map) Keys() []string {
+	keys := make([]string, len(m))
+	i := 0
+	for key := range m {
+		keys[i] = key
+		i++
+	}
+	return keys
+}
+
 // Clone makes a copy of the Map
 func (m Map) Clone() Map {
 	clone := make(Map)

properties_test.go

@@ -30,6 +30,7 @@
 package properties
 
 import (
+	"fmt"
 	"path/filepath"
 	"runtime"
 	"testing"
@@ -171,3 +172,12 @@ func TestGetSetBoolean(t *testing.T) {
 	require.Equal(t, "true", m["e"])
 	require.Equal(t, "false", m["f"])
 }
+
+func TestKeysMethod(t *testing.T) {
+	m := Map{
+		"k1":    "value",
+		"k2":    "othervalue",
+		"k3.k4": "anothevalue",
+	}
+	require.Equal(t, "[k1 k2 k3.k4]", fmt.Sprintf("%s", m.Keys()))
+}