added a flag to indent or not indent the sequence

.gitignore

@@ -0,0 +1 @@
+.vscode

emitterc.go

@@ -241,7 +241,7 @@ func yaml_emitter_increase_indent(emitter *yaml_emitter_t, flow, indentless bool
 			emitter.indent += 2
 		} else {
 			// Everything else aligns to the chosen indentation.
-			emitter.indent = emitter.best_indent*((emitter.indent+emitter.best_indent)/emitter.best_indent)
+			emitter.indent = emitter.best_indent * ((emitter.indent + emitter.best_indent) / emitter.best_indent)
 		}
 	}
 	return true
@@ -728,7 +728,7 @@ func yaml_emitter_emit_flow_mapping_value(emitter *yaml_emitter_t, event *yaml_e
 // Expect a block item node.
 func yaml_emitter_emit_block_sequence_item(emitter *yaml_emitter_t, event *yaml_event_t, first bool) bool {
 	if first {
-		if !yaml_emitter_increase_indent(emitter, false, false) {
+		if !yaml_emitter_increase_indent(emitter, false, emitter.sameLevelSequence) {
 			return false
 		}
 	}

encode.go

@@ -29,12 +29,13 @@ import (
 )
 
 type encoder struct {
-	emitter  yaml_emitter_t
-	event    yaml_event_t
-	out      []byte
-	flow     bool
-	indent   int
-	doneInit bool
+	emitter           yaml_emitter_t
+	event             yaml_event_t
+	out               []byte
+	flow              bool
+	indent            int
+	sameLevelSequence bool
+	doneInit          bool
 }
 
 func newEncoder() *encoder {
@@ -60,6 +61,7 @@ func (e *encoder) init() {
 	if e.indent == 0 {
 		e.indent = 4
 	}
+	e.emitter.sameLevelSequence = e.sameLevelSequence
 	e.emitter.best_indent = e.indent
 	yaml_stream_start_event_initialize(&e.event, yaml_UTF8_ENCODING)
 	e.emit()

encode_test.go

@@ -656,6 +656,18 @@ func (s *S) TestSetIndent(c *C) {
 	c.Assert(buf.String(), Equals, "a:\n        b:\n                c: d\n")
 }
 
+// This test is providing coverage for SetIndentSequences function.
+// When we are setting that to false the sequences are not indented.
+func (s *S) TestSetIndentSequences(c *C) {
+	var buf bytes.Buffer
+	enc := yaml.NewEncoder(&buf)
+	enc.SetIndentSequences(false)
+
+	err := enc.Encode(map[string][]string{"a": {"b", "c"}})
+	c.Assert(err, Equals, nil)
+	c.Assert(buf.String(), Equals, "a:\n- b\n- c\n")
+}
+
 func (s *S) TestSortedOutput(c *C) {
 	order := []interface{}{
 		false,

yaml.go

@@ -278,6 +278,28 @@ func (e *Encoder) SetIndent(spaces int) {
 	e.encoder.indent = spaces
 }
 
+// SetIndentSequences allows you to control how the sequences are indented
+// in in v3 sequences started getting indented like this:
+//
+// fruits
+//   - apple
+//   - orange
+//
+// set this flag to false in order to stop indenting sequences and get output
+// like this:
+//
+// fruits
+// - apple
+// - orange
+func (e *Encoder) SetIndentSequences(indent bool) {
+	// NOTE: why is this backwards?
+	// The reason is that encoders get initialized at various places
+	// and when people use Marshall they don't get a chance to call this
+	// function.  So we choose a boolean with a meaningful value of false
+	// for backwards compatibility with exiting v3 clients.
+	e.encoder.sameLevelSequence = !indent
+}
+
 // Close closes the encoder by writing any remaining data.
 // It does not write a stream terminating string "...".
 func (e *Encoder) Close() (err error) {
@@ -363,7 +385,7 @@ const (
 //             Address yaml.Node
 //     }
 //     err := yaml.Unmarshal(data, &person)
-// 
+//
 // Or by itself:
 //
 //     var person Node
@@ -373,7 +395,7 @@ type Node struct {
 	// Kind defines whether the node is a document, a mapping, a sequence,
 	// a scalar value, or an alias to another node. The specific data type of
 	// scalar nodes may be obtained via the ShortTag and LongTag methods.
-	Kind  Kind
+	Kind Kind
 
 	// Style allows customizing the apperance of the node in the tree.
 	Style Style
@@ -421,7 +443,6 @@ func (n *Node) IsZero() bool {
 		n.HeadComment == "" && n.LineComment == "" && n.FootComment == "" && n.Line == 0 && n.Column == 0
 }
 
-
 // LongTag returns the long form of the tag that indicates the data type for
 // the node. If the Tag field isn't explicitly defined, one will be computed
 // based on the node properties.

yamlh.go

@@ -639,7 +639,6 @@ type yaml_parser_t struct {
 }
 
 type yaml_comment_t struct {
-
 	scan_mark  yaml_mark_t // Position where scanning for comments started
 	token_mark yaml_mark_t // Position after which tokens will be associated with this comment
 	start_mark yaml_mark_t // Position of '#' comment mark
@@ -740,7 +739,8 @@ type yaml_emitter_t struct {
 
 	tag_directives []yaml_tag_directive_t // The list of tag directives.
 
-	indent int // The current indentation level.
+	indent            int  // The current indentation level.
+	sameLevelSequence bool // Keep sequences at same level fo indent
 
 	flow_level int // The current flow level.