Add special case for end tag </br>. Fixes #185

Normally, an end tag for a void element would simply be discarded,
but the spec includes a special rule as follows:

> An end tag whose tag name is "br"
> Parse error. Drop the attributes from the token, and act as
> described in the next entry; i.e. act as if this was a "br"
> start tag token with no attributes, rather than the end tag
> token that it actually is.

1 files changed, 8 insertions, 2 deletions

diff --git a/src/HTML5/Parser/DOMTreeBuilder.php b/src/HTML5/Parser/DOMTreeBuilder.php
index e9bca4e..448dec7 100644
--- a/src/HTML5/Parser/DOMTreeBuilder.php
+++ b/src/HTML5/Parser/DOMTreeBuilder.php
@@ -474,8 +474,14 @@ class DOMTreeBuilder implements EventHandler
     {
         $lname = $this->normalizeTagName($name);
 
-        // Ignore closing tags for unary elements.
-        if (Elements::isA($name, Elements::VOID_TAG)) {
+        // Special case within 12.2.6.4.7: An end tag whose tag name is "br" should be treated as an opening tag
+        if ($name === 'br') {
+            $this->parseError('Closing tag encountered for void element br.');
+
+            $this->startTag('br');
+        }
+        // Ignore closing tags for other unary elements.
+        elseif (Elements::isA($name, Elements::VOID_TAG)) {
             return;
         }