Ensure empty inline svg and math tags are serialized as void tags

ohader · ohader · commit c97a75a6517e · 2025-03-07T11:17:16.000+01:00
Before this change, e.g. `&lt;svg&gt;&lt;/svg&gt;` has been incorrectly
serialized as `&lt;svg /&gt;&lt;/svg&gt;`. This change ensures, that the
result is a proper (self-closing) void tag `&lt;svg /&gt;`.
diff --git a/src/HTML5/Serializer/OutputRules.php b/src/HTML5/Serializer/OutputRules.php
@@ -206,6 +206,9 @@ protected function doctype()
         $this->nl();
     }
 
+    /**
+     * @param \DOMElement $ele
+     */
     public function element($ele)
     {
         $name = $ele->tagName;
@@ -227,6 +230,9 @@ public function element($ele)
         }
 
         $this->openTag($ele);
+        // The tag is already self-closed (`<svg />` or `<math />`) in `openTag` if there are no child nodes.
+        $handledAsVoidTag = $this->outputMode !== static::IM_IN_HTML && !$ele->hasChildNodes();
+
         if (Elements::isA($name, Elements::TEXT_RAW)) {
             foreach ($ele->childNodes as $child) {
                 if ($child instanceof \DOMCharacterData) {
@@ -248,7 +254,7 @@ public function element($ele)
         }
 
         // If not unary, add a closing tag.
-        if (!Elements::isA($name, Elements::VOID_TAG)) {
+        if (!$handledAsVoidTag && !Elements::isA($name, Elements::VOID_TAG)) {
             $this->closeTag($ele);
         }
     }
diff --git a/test/HTML5/Serializer/OutputRulesTest.php b/test/HTML5/Serializer/OutputRulesTest.php
@@ -652,4 +652,21 @@ public function testHandlingInvalidRawContent()
            <h1>Hello!</h1>
        <p>Bar</p></script>'));
     }
+
+    public function testSvgAndMathElementsWithoutChildNodesAreHandledAsVoidTags()
+    {
+        $dom = $this->html5->loadHTML(
+            '<!doctype html>
+<html lang="en" id="base">
+    <body>
+       <svg></svg>
+       <math></math>
+    </body>
+</html>');
+
+        $contents = $this->html5->saveHTML($dom);
+
+        self::assertRegExp('|^\h*<svg />$|m', $contents);
+        self::assertRegExp('|^\h*<math />$|m', $contents);
+    }
 }

Original file line number	Diff line number	Diff line change
`@@ -206,6 +206,9 @@ protected function doctype()`
`206`	`206`	`$this->nl();`
`207`	`207`	`}`
`208`	`208`
	`209`	`+ /**`
	`210`	`+ * @param \DOMElement $ele`
	`211`	`+ */`
`209`	`212`	`public function element($ele)`
`210`	`213`	`{`
`211`	`214`	`$name = $ele->tagName;`
`@@ -227,6 +230,9 @@ public function element($ele)`
`227`	`230`	`}`
`228`	`231`
`229`	`232`	`$this->openTag($ele);`
	`233`	+ // The tag is already self-closed (`<svg />` or `<math />`) in `openTag` if there are no child nodes.
	`234`	`+ $handledAsVoidTag = $this->outputMode !== static::IM_IN_HTML && !$ele->hasChildNodes();`
	`235`	`+`
`230`	`236`	`if (Elements::isA($name, Elements::TEXT_RAW)) {`
`231`	`237`	`foreach ($ele->childNodes as $child) {`
`232`	`238`	`if ($child instanceof \DOMCharacterData) {`
`@@ -248,7 +254,7 @@ public function element($ele)`
`248`	`254`	`}`
`249`	`255`
`250`	`256`	`// If not unary, add a closing tag.`
`251`		`- if (!Elements::isA($name, Elements::VOID_TAG)) {`
	`257`	`+ if (!$handledAsVoidTag && !Elements::isA($name, Elements::VOID_TAG)) {`
`252`	`258`	`$this->closeTag($ele);`
`253`	`259`	`}`
`254`	`260`	`}`