Inline comments before body token { breaks parser (#119)

* issue #118 , enum group message oneof

* process comment-before-body in service

Author: emicklei

comment.go

@@ -144,3 +144,16 @@ func mergeOrReturnComment(elements []Visitee, lit string, pos scanner.Position)
 
 // parent is part of elementContainer
 func (c *Comment) parent(Visitee) {}
+
+// consumeCommentFor is for reading and taking all comment lines before the body of an element (starting at {)
+func consumeCommentFor(p *Parser, e elementContainer) {
+	pos, tok, lit := p.next()
+	if tok == tCOMMENT {
+		if com := mergeOrReturnComment(e.elements(), lit, pos); com != nil { // not merged?
+			e.addElement(com)
+		}
+		consumeCommentFor(p, e) // bit of recursion is fine
+	} else {
+		p.nextPut(pos, tok, lit)
+	}
+}

enum.go

@@ -72,6 +72,7 @@ func (e *Enum) parse(p *Parser) error {
 		}
 	}
 	e.Name = lit
+	consumeCommentFor(p, e)
 	_, tok, lit = p.next()
 	if tok != tLEFTCURLY {
 		return p.unexpected(lit, "enum opening {", e)

enum_test.go

@@ -142,3 +142,26 @@ func TestEnumWithHex(t *testing.T) {
 		t.Errorf("got [%v] want [%v]", got, want)
 	}
 }
+
+func TestEnumInlineCommentBeforeBody(t *testing.T) {
+	src := `enum BarEnum // BarEnum
+	  // with another line
+	  {
+		  BAR_TYPE_INVALID= 0;
+		  BAR_TYPE_BAD = 1;
+	  } 
+	`
+	p := newParserOn(src)
+	e := new(Enum)
+	p.next()
+	if err := e.parse(p); err != nil {
+		t.Fatal(err)
+	}
+	nestedComment := e.Elements[0].(*Comment)
+	if nestedComment == nil {
+		t.Fatal("expected comment present")
+	}
+	if got, want := len(nestedComment.Lines), 2; got != want {
+		t.Errorf("got %d want %d lines", got, want)
+	}
+}

group.go

@@ -88,6 +88,7 @@ func (g *Group) parse(p *Parser) error {
 		return p.unexpected(lit, "group sequence number", g)
 	}
 	g.Sequence = i
+	consumeCommentFor(p, g)
 	_, tok, lit = p.next()
 	if tok != tLEFTCURLY {
 		return p.unexpected(lit, "group opening {", g)

group_test.go

@@ -28,7 +28,9 @@ import "testing"
 func TestGroup(t *testing.T) {
 	oto := `message M {
 		// group
-        optional group OptionalGroup = 16 {
+		optional group OptionalGroup = 16 // group comment 1
+			// group comment 2 
+		{
 			// field
             optional int32 a = 17;
         }
@@ -45,7 +47,7 @@ func TestGroup(t *testing.T) {
 		t.Fatalf("got [%v] want [%v]", got, want)
 	}
 	g := m.Elements[0].(*Group)
-	if got, want := len(g.Elements), 1; got != want {
+	if got, want := len(g.Elements), 2; got != want {
 		t.Fatalf("got [%v] want [%v]", got, want)
 	}
 	if got, want := g.Position.Line, 3; got != want {
@@ -54,7 +56,7 @@ func TestGroup(t *testing.T) {
 	if got, want := g.Comment != nil, true; got != want {
 		t.Errorf("got [%v] want [%v]", got, want)
 	}
-	f := g.Elements[0].(*NormalField)
+	f := g.Elements[1].(*NormalField)
 	if got, want := f.Name, "a"; got != want {
 		t.Errorf("got [%v] want [%v]", got, want)
 	}

message.go

@@ -53,6 +53,7 @@ func (m *Message) parse(p *Parser) error {
 		}
 	}
 	m.Name = lit
+	consumeCommentFor(p, m)
 	_, tok, lit = p.next()
 	if tok != tLEFTCURLY {
 		return p.unexpected(lit, m.groupName()+" opening {", m)

message_test.go

@@ -152,3 +152,25 @@ func TestSingleQuotedReservedNames(t *testing.T) {
 		t.Fatalf("got [%v] want [%v]", got, want)
 	}
 }
+
+func TestMessageInlineCommentBeforeBody(t *testing.T) {
+	src := `message BarMessage // BarMessage
+	  // with another line
+	  {
+		  name string = 1;
+	  } 
+	`
+	p := newParserOn(src)
+	msg := new(Message)
+	p.next()
+	if err := msg.parse(p); err != nil {
+		t.Fatal(err)
+	}
+	nestedComment := msg.Elements[0].(*Comment)
+	if nestedComment == nil {
+		t.Fatal("expected comment present")
+	}
+	if got, want := len(nestedComment.Lines), 2; got != want {
+		t.Errorf("got %d want %d lines", got, want)
+	}
+}

oneof.go

@@ -64,6 +64,7 @@ func (o *Oneof) parse(p *Parser) error {
 		}
 	}
 	o.Name = lit
+	consumeCommentFor(p, o)
 	pos, tok, lit = p.next()
 	if tok != tLEFTCURLY {
 		return p.unexpected(lit, "oneof opening {", o)

oneof_test.go

@@ -142,3 +142,25 @@ func TestOneOfWithOption(t *testing.T) {
 		t.Errorf("got [%v] want [%v]", got, want)
 	}
 }
+
+func TestOneofInlineCommentBeforeBody(t *testing.T) {
+	src := `oneof BarOption // BarOption
+	  // with another line
+	  {
+		  name string = 1;
+	  } 
+	`
+	p := newParserOn(src)
+	oneof := new(Oneof)
+	p.next()
+	if err := oneof.parse(p); err != nil {
+		t.Fatal(err)
+	}
+	nestedComment := oneof.Elements[0].(*Comment)
+	if nestedComment == nil {
+		t.Fatal("expected comment present")
+	}
+	if got, want := len(nestedComment.Lines), 2; got != want {
+		t.Errorf("got %d want %d lines", got, want)
+	}
+}

service.go

@@ -73,6 +73,7 @@ func (s *Service) parse(p *Parser) error {
 		}
 	}
 	s.Name = lit
+	consumeCommentFor(p, s)
 	pos, tok, lit = p.next()
 	if tok != tLEFTCURLY {
 		return p.unexpected(lit, "service opening {", s)

service_test.go

@@ -183,3 +183,27 @@ func TestRPCWithTypeThatHasLeadingDot(t *testing.T) {
 		t.Fatal(err)
 	}
 }
+
+func TestServiceInlineCommentBeforeBody(t *testing.T) {
+	src := `service BarService // BarService
+	  // with another line
+	  {
+		rpc Foo (Void) returns (Magic) // FooRPC {
+			// yet another line
+		}
+	  } 
+	`
+	p := newParserOn(src)
+	svc := new(Service)
+	p.next()
+	if err := svc.parse(p); err != nil {
+		t.Fatal(err)
+	}
+	nestedComment := svc.Elements[0].(*Comment)
+	if nestedComment == nil {
+		t.Fatal("expected comment present")
+	}
+	if got, want := len(nestedComment.Lines), 2; got != want {
+		t.Errorf("got %d want %d lines", got, want)
+	}
+}