func (p *parser) readExtension(ext *ast.Extension) *parseError {
if err := p.readToken("extend"); err != nil {
return err
}
ext.Position = p.cur.astPosition()
tok := p.next()
if tok.err != nil {
return tok.err
}
ext.Extendee = tok.value // checked during resolution
if err := p.readToken("{"); err != nil {
return err
}
for !p.done {
tok := p.next()
if tok.err != nil {
return tok.err
}
if tok.value == "}" {
// end of extension
return nil
}
p.back()
field := new(ast.Field)
ext.Fields = append(ext.Fields, field)
field.Up = ext // p.readFile uses this
if err := p.readField(field); err != nil {
return err
}
}
return p.errorf("unexpected EOF while parsing extension")
}
func (p *parser) readMessageContents(msg *ast.Message) *parseError {
// Parse message fields and other things inside a message.
var oneof *ast.Oneof // set while inside a oneof
for !p.done {
tok := p.next()
if tok.err != nil {
return tok.err
}
switch tok.value {
case "extend":
// extension
p.back()
ext := new(ast.Extension)
msg.Extensions = append(msg.Extensions, ext)
if err := p.readExtension(ext); err != nil {
return err
}
ext.Up = msg
case "oneof":
// oneof
if oneof != nil {
return p.errorf("nested oneof not permitted")
}
oneof = new(ast.Oneof)
msg.Oneofs = append(msg.Oneofs, oneof)
oneof.Position = p.cur.astPosition()
tok := p.next()
if tok.err != nil {
return tok.err
}
oneof.Name = tok.value // TODO: validate
oneof.Up = msg
if err := p.readToken("{"); err != nil {
return err
}
case "message":
// nested message
p.back()
nmsg := new(ast.Message)
msg.Messages = append(msg.Messages, nmsg)
if err := p.readMessage(nmsg); err != nil {
return err
}
nmsg.Up = msg
case "enum":
// nested enum
p.back()
ne := new(ast.Enum)
msg.Enums = append(msg.Enums, ne)
if err := p.readEnum(ne); err != nil {
return err
}
ne.Up = msg
case "extensions":
// extension range
p.back()
r, err := p.readExtensionRange()
if err != nil {
return err
}
msg.ExtensionRanges = append(msg.ExtensionRanges, r...)
default:
// field; this token is required/optional/repeated,
// a primitive type, or a named type.
p.back()
field := new(ast.Field)
msg.Fields = append(msg.Fields, field)
field.Oneof = oneof
field.Up = msg // p.readField uses this
if err := p.readField(field); err != nil {
return err
}
case "}":
if oneof != nil {
// end of oneof
oneof = nil
continue
}
// end of message
p.back()
return nil
}
}
return p.errorf("unexpected EOF while parsing message")
}