Fix bug introduced by mapstr optimization. (#65)

* Fix bug introduced by mapstr optimization.

The bug was introduced by
#64.

Add a test to catch the bug that slipped through.

* Update changelog for 0.2.7

Author: cmacknz

CHANGELOG.md

@@ -14,6 +14,12 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Fixed
 
+## [0.2.7]
+
+### Changed
+
+- Fix bug introduced by mapstr optimization: #65
+
 ## [0.2.6]
 
 ### Added

mapstr/mapstr.go

@@ -157,8 +157,9 @@ func (m M) Clone() M {
 	for k := range m {
 		if innerMap, ok := (m[k]).(M); ok {
 			result[k] = innerMap.Clone()
+		} else {
+			result[k] = m[k]
 		}
-		result[k] = m[k]
 	}
 
 	return result

mapstr/mapstr_test.go

@@ -343,7 +343,7 @@ func TestMapStrGetValue(t *testing.T) {
 func TestClone(t *testing.T) {
 	assert := assert.New(t)
 
-	m := M{
+	original := M{
 		"c1": 1,
 		"c2": 2,
 		"c3": M{
@@ -352,8 +352,36 @@ func TestClone(t *testing.T) {
 		},
 	}
 
-	c := m.Clone()
-	assert.Equal(M{"c31": 1, "c32": 2}, c["c3"])
+	// Clone the original mapstr and then increment every value in it. Ensures the test will fail if
+	// the cloned mapstr kept a reference to any part of the original.
+	cloned := original.Clone()
+	incrementMapstrValues(original)
+
+	// Ensure that the cloned copy is as expected and no longer matches the original mapstr.
+	assert.Equal(
+		M{
+			"c1": 1,
+			"c2": 2,
+			"c3": M{
+				"c31": 1,
+				"c32": 2,
+			},
+		},
+		cloned,
+	)
+	assert.NotEqual(cloned, original)
+}
+
+func incrementMapstrValues(m M) {
+	for k := range m {
+		switch v := m[k].(type) {
+		case int:
+			m[k] = v + 1
+		case M:
+			incrementMapstrValues(m[k].(M))
+		}
+
+	}
 }
 
 func BenchmarkClone(b *testing.B) {