code review 5395045: html: parse </optgroup> and </option>

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 1227 matching lines @@
                 case "input", "keygen", "textarea":
                         // TODO.
                 case "script":
                         // TODO.
                 default:
                         // Ignore the token.
                 }
         case EndTagToken:
                 switch p.tok.Data {
                 case "option":
-                        // TODO.
+                        if p.top().Data == "option" {
+                                p.oe.pop()
+                        }
                 case "optgroup":
-                        // TODO.
+                        i := len(p.oe) - 1
+                        if p.oe[i].Data == "option" {
+                                i--
+                        }
+                        if p.oe[i].Data == "optgroup" {
+                                p.oe = p.oe[:i]
+                        }
                 case "select":
                         endSelect = true
                 default:
                         // Ignore the token.
                 }
         case CommentToken:
                 p.doc.Add(&Node{
                         Type: CommentNode,
                         Data: p.tok.Data,
                 })
@@ skipping 181 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
 }