handle comments inside literal of option (emicklei#139)

option.go

@@ -135,6 +135,10 @@ type Literal struct {
 	Source   string
 	IsString bool
 
+	// It not nil then the entry is actually a comment with line(s)
+	// modelled this way because Literal is not an elementContainer
+	Comment *Comment
+
 	// The rune use to delimit the string value (only valid iff IsString)
 	QuoteRune rune
 
@@ -191,6 +195,17 @@ func (l Literal) SourceRepresentation() string {
 // parse expects to read a literal constant after =.
 func (l *Literal) parse(p *Parser) error {
 	pos, tok, lit := p.next()
+	// handle special element inside literal, a comment line
+	if isComment(lit) {
+		nc := newComment(pos, lit)
+		if l.Comment == nil {
+			l.Comment = nc
+		} else {
+			l.Comment.Merge(nc)
+		}
+		// continue with remaining entries
+		return l.parse(p)
+	}
 	if tok == tLEFTSQUARE {
 		// collect array elements
 		array := []*Literal{}

option_test.go

@@ -741,3 +741,30 @@ func TestStringValuesParsedAsNumbers(t *testing.T) {
 		t.Errorf("got [%v:%T] want [%v:%T]", got, got, want, want)
 	}
 }
+
+func TestCommentInsideArray(t *testing.T) {
+	src := `option test = {
+			scope_rules : [
+			  // A comment
+			  // Another comment
+			  {has : [ 
+				// comment on test
+				"test" 
+			  ]}
+			]
+		  };
+		`
+	opt, err := newParserOn(src).Parse()
+	if err != nil {
+		t.Fatal(err)
+	}
+	opt2 := opt.Elements[0].(*Option)
+	scp, _ := opt2.Constant.OrderedMap.Get("scope_rules")
+	elem0 := scp.Array[0]
+	t.Log("comment:", elem0.Comment.Lines)
+	has, _ := elem0.OrderedMap.Get("has")
+	if got, want := has.Array[0].Source, "test"; got != want {
+		t.Errorf("got [%v:%T] want [%v:%T]", got, got, want, want)
+	}
+	t.Log("comment:", has.Array[0].Comment.Lines)
+}