issue #48 : allow multiple enum value options + field.ValueOption -> …

…field.Elements

enum.go

@@ -119,7 +119,7 @@ type EnumField struct {
 	Comment       *Comment
 	Name          string
 	Integer       int
-	ValueOption   *Option
+	Elements      []Visitee // such as Option and Comment
 	InlineComment *Comment
 }
 
@@ -157,17 +157,22 @@ func (f *EnumField) parse(p *Parser) error {
 	f.Integer = i
 	pos, tok, lit = p.next()
 	if tok == tLEFTSQUARE {
-		o := new(Option)
-		o.Position = pos
-		o.IsEmbedded = true
-		err := o.parse(p)
-		if err != nil {
-			return err
-		}
-		f.ValueOption = o
-		pos, tok, lit = p.next()
-		if tok != tRIGHTSQUARE {
-			return p.unexpected(lit, "option closing ]", f)
+		for {
+			o := new(Option)
+			o.Position = pos
+			o.IsEmbedded = true
+			err := o.parse(p)
+			if err != nil {
+				return err
+			}
+			f.Elements = append(f.Elements, o)
+			pos, tok, lit = p.next()
+			if tok == tCOMMA {
+				continue
+			}
+			if tok == tRIGHTSQUARE {
+				break
+			}
 		}
 	}
 	if tSEMICOLON == tok {

enum_test.go

@@ -34,6 +34,10 @@ enum EnumAllowingAlias {
   STARTED = 1;
   RUNNING = 2 [(custom_option) = "hello world"];
   NEG = -42;
+  SOMETHING_FOO = 0 [
+    (bar.enum_value_option) = true,
+    (bar.enum_value_dep_option) = { hello: 1 }
+  ];  
 }`
 	p := newParserOn(proto)
 	pr, err := p.Parse()
@@ -44,7 +48,7 @@ enum EnumAllowingAlias {
 	if got, want := len(enums), 1; got != want {
 		t.Errorf("got [%v] want [%v]", got, want)
 	}
-	if got, want := len(enums[0].Elements), 5; got != want {
+	if got, want := len(enums[0].Elements), 6; got != want {
 		t.Errorf("got [%v] want [%v]", got, want)
 	}
 	if got, want := enums[0].Comment != nil, true; got != want {
@@ -67,10 +71,11 @@ enum EnumAllowingAlias {
 	if got, want := ef3.Integer, 2; got != want {
 		t.Errorf("got [%v] want [%v]", got, want)
 	}
-	if got, want := ef3.ValueOption.Name, "(custom_option)"; got != want {
+	ef3opt := ef3.Elements[0].(*Option)
+	if got, want := ef3opt.Name, "(custom_option)"; got != want {
 		t.Errorf("got [%v] want [%v]", got, want)
 	}
-	if got, want := ef3.ValueOption.Constant.Source, "hello world"; got != want {
+	if got, want := ef3opt.Constant.Source, "hello world"; got != want {
 		t.Errorf("got [%v] want [%v]", got, want)
 	}
 	if got, want := ef3.Position.Line, 7; got != want {