code review 5393045: html: parse <optgroup> tags

src/pkg/html/parse.go

 // Copyright 2010 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
 package html
 
 import (
         "io"
         "strings"
 )
@@ skipping 1208 matching lines @@
         case StartTagToken:
                 switch p.tok.Data {
                 case "html":
                         // TODO.
                 case "option":
                         if p.top().Data == "option" {
                                 p.oe.pop()
                         }
                         p.addElement(p.tok.Data, p.tok.Attr)
                 case "optgroup":
-                        // TODO.
+                        if p.top().Data == "option" {
+                                p.oe.pop()
+                        }
+                        if p.top().Data == "optgroup" {
+                                p.oe.pop()
+                        }
+                        p.addElement(p.tok.Data, p.tok.Attr)
                 case "select":
                         endSelect = true
                 case "input", "keygen", "textarea":
                         // TODO.
                 case "script":
                         // TODO.
                 default:
                         // Ignore the token.
                 }
         case EndTagToken:
@@ skipping 196 matching lines @@
                 consumed = p.im(p)
         }
         // Loop until the final token (the ErrorToken signifying EOF) is consumed.
         for {
                 if consumed = p.im(p); consumed {
                         break
                 }
         }
         return p.doc, nil
 }