From 28c29656af08a9d1b8a48c80004be55fa09b0806 Mon Sep 17 00:00:00 2001
From: "Edward Z. Yang" <edwardzyang@thewritingpot.com>
Date: Sun, 9 Sep 2007 01:27:09 +0000
Subject: [PATCH] [2.1.3] Fix off-by-one bug in injector functionality for
 dormant injectors

git-svn-id: http://htmlpurifier.org/svnroot/htmlpurifier/trunk@1415 48356398-32a2-884e-a903-53898d9a118a
---
 NEWS                                                      | 2 ++
 library/HTMLPurifier/Injector.php                         | 3 +++
 library/HTMLPurifier/Strategy/MakeWellFormed.php          | 8 +++++++-
 .../HTMLPurifier/Strategy/MakeWellFormed_InjectorTest.php | 7 +++++++
 4 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/NEWS b/NEWS
index 98f7a642..0027c556 100644
--- a/NEWS
+++ b/NEWS
@@ -12,6 +12,8 @@ NEWS ( CHANGELOG and HISTORY )                                     HTMLPurifier
 2.1.3, unknown release date
 - Fixed poor include ordering for Email URI AttrDefs, causes fatal errors
   on some systems.
+- Injector algorithm further refined: off-by-one error regarding skip 
+  counts for dormant injectors fixed
 
 2.1.2, released 2007-09-03
 ! Implemented Object module for trusted users
diff --git a/library/HTMLPurifier/Injector.php b/library/HTMLPurifier/Injector.php
index 59017163..261a2a80 100644
--- a/library/HTMLPurifier/Injector.php
+++ b/library/HTMLPurifier/Injector.php
@@ -4,6 +4,9 @@
  * Injects tokens into the document while parsing for well-formedness.
  * This enables "formatter-like" functionality such as auto-paragraphing,
  * smiley-ification and linkification to take place.
+ * 
+ * @todo Allow injectors to request a re-run on their output. This 
+ *       would help if an operation is recursive.
  */
 class HTMLPurifier_Injector
 {
diff --git a/library/HTMLPurifier/Strategy/MakeWellFormed.php b/library/HTMLPurifier/Strategy/MakeWellFormed.php
index b3e8aa74..b8173f6d 100644
--- a/library/HTMLPurifier/Strategy/MakeWellFormed.php
+++ b/library/HTMLPurifier/Strategy/MakeWellFormed.php
@@ -286,8 +286,14 @@ class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy
             
             // adjust the injector skips based on the array substitution
             if ($this->injectors) {
-                $offset = count($token) + 1;
+                $offset = count($token);
                 for ($i = 0; $i <= $this->currentInjector; $i++) {
+                    // because of the skip back, we need to add one more
+                    // for uninitialized injectors. I'm not exactly
+                    // sure why this is the case, but I think it has to
+                    // do with the fact that we're decrementing skips
+                    // before re-checking text
+                    if (!$this->injectors[$i]->skip) $this->injectors[$i]->skip++;
                     $this->injectors[$i]->skip += $offset;
                 }
             }
diff --git a/tests/HTMLPurifier/Strategy/MakeWellFormed_InjectorTest.php b/tests/HTMLPurifier/Strategy/MakeWellFormed_InjectorTest.php
index e8e6c797..04756201 100644
--- a/tests/HTMLPurifier/Strategy/MakeWellFormed_InjectorTest.php
+++ b/tests/HTMLPurifier/Strategy/MakeWellFormed_InjectorTest.php
@@ -62,4 +62,11 @@ class HTMLPurifier_Strategy_MakeWellFormed_InjectorTest extends HTMLPurifier_Str
         );
     }
     
+    function testParagraphAfterLinkifiedURL() {
+        $this->assertResult(
+            "http://google.com\n\n<b>b</b>",
+            "<p><a href=\"http://google.com\">http://google.com</a></p><p><b>b</b></p>"
+        );
+    }
+    
 }