Merge pull request #5 from r6min/fix-comment-marshalling

Fix marshalling for comments preceding sequenced items with keys

encode.go

@@ -308,6 +308,26 @@ func (e *encoder) sequenceitemv(tag string, in reflect.Value) {
 				continue
 			}
 
+			// Check if the value is a MapSlice
+			if reflect.TypeOf(item.Value) == reflect.TypeOf(MapSlice{}) {
+				itemSlice := item.Value.(MapSlice)
+				endIndex := 0
+
+				for index, subItem := range itemSlice {
+					endIndex = index
+
+					// check if the value is a comment
+					if subItem.Value == nil && len(subItem.Comment) > 0 {
+						// If the subitem is a comment, add it before beginning the sequence
+						e.commentv([]byte(subItem.Comment))
+					} else {
+						break
+					} 
+				}
+				// remove all comments to avoid double printing
+				item.Value = itemSlice[endIndex:len(itemSlice)]
+			}
+
 			e.marshal("", reflect.ValueOf(item.Value))
 
 			// Note that empty end-of-line comments are ignored

encode_test.go

@@ -402,6 +402,27 @@ var marshalTests = []struct {
 		},
 		"a:\n  b:\n  # my comment\n  - 3\n  # my comment 2\n  - 8\n",
 	},
+	{ // sequence containing mapitems preceded by comments
+		&yaml.MapSlice{
+			{Key: "a", Value: yaml.MapSlice{
+				{Key: "b", Value: []yaml.SequenceItem{
+					{Value: yaml.MapSlice{
+						{Key: nil, Value: nil, Comment: " my comment"},
+						{Key: nil, Value: nil, Comment: " my comment 2"},
+						{Key: "a", Value: 3, Comment: ""},
+						{Key: "b", Value: 7, Comment: ""},
+						{Key: nil, Value: nil, Comment: " my comment 3"},
+					}, Comment: ""},
+					{Value: yaml.MapSlice{
+						{Key: nil, Value: nil, Comment: " my comment 4"},
+						{Key: "a", Value: 9, Comment: ""},
+						{Key: "b", Value: 2, Comment: ""},
+					}, Comment: ""},
+				}, Comment: ""},
+			}, Comment: ""},
+		},
+		"a:\n  b:\n  # my comment\n  # my comment 2\n  - a: 3\n    b: 7\n    # my comment 3\n  # my comment 4\n  - a: 9\n    b: 2\n",
+	},
 	{ // key comment (non-primitive value)
 		&yaml.MapSlice{
 			{Key: "a", Value: yaml.MapSlice{