diff --git a/src/Symfony/Component/DomCrawler/Crawler.php b/src/Symfony/Component/DomCrawler/Crawler.php
index a45cc86cb2..208181648a 100644
--- a/src/Symfony/Component/DomCrawler/Crawler.php
+++ b/src/Symfony/Component/DomCrawler/Crawler.php
@@ -188,8 +188,7 @@ class Crawler implements \Countable, \IteratorAggregate
*/
public function addHtmlContent($content, $charset = 'UTF-8')
{
- // Use HTML5 parser if the content is HTML5 and the library is available
- $dom = null !== $this->html5Parser && strspn($content, " \t\r\n") === stripos($content, '') ? $this->parseHtml5($content, $charset) : $this->parseXhtml($content, $charset);
+ $dom = $this->parseHtmlString($content, $charset);
$this->addDocument($dom);
$base = $this->filterRelativeXPath('descendant-or-self::base')->extract(['href']);
@@ -1295,4 +1294,35 @@ class Crawler implements \Countable, \IteratorAggregate
return new CssSelectorConverter($this->isHtml);
}
+
+ /**
+ * Parse string into DOMDocument object using HTML5 parser if the content is HTML5 and the library is available.
+ * Use libxml parser otherwise.
+ */
+ private function parseHtmlString(string $content, string $charset): \DOMDocument
+ {
+ if ($this->canParseHtml5String($content)) {
+ return $this->parseHtml5($content, $charset);
+ }
+
+ return $this->parseXhtml($content, $charset);
+ }
+
+ private function canParseHtml5String(string $content): bool
+ {
+ if (null === $this->html5Parser) {
+ return false;
+ }
+ if (false === ($pos = stripos($content, ''))) {
+ return false;
+ }
+ $header = substr($content, 0, $pos);
+
+ return '' === $header || $this->isValidHtml5Heading($header);
+ }
+
+ private function isValidHtml5Heading(string $heading): bool
+ {
+ return 1 === preg_match('/^\x{FEFF}?\s*(\s*)*$/u', $heading);
+ }
}
diff --git a/src/Symfony/Component/DomCrawler/Tests/Html5ParserCrawlerTest.php b/src/Symfony/Component/DomCrawler/Tests/Html5ParserCrawlerTest.php
index 8ada3794d7..a4aa7740dd 100644
--- a/src/Symfony/Component/DomCrawler/Tests/Html5ParserCrawlerTest.php
+++ b/src/Symfony/Component/DomCrawler/Tests/Html5ParserCrawlerTest.php
@@ -25,4 +25,56 @@ class Html5ParserCrawlerTest extends AbstractCrawlerTest
$crawler->add($this->getDoctype().'Foo
');
$this->assertEquals('Foo', $crawler->filterXPath('//h1')->text(), '->add() adds nodes from a string');
}
+
+ /** @dataProvider validHtml5Provider */
+ public function testHtml5ParserParseContentStartingWithValidHeading(string $content): void
+ {
+ $this->skipTestIfHTML5LibraryNotAvailable();
+
+ $crawler = $this->createCrawler();
+ $crawler->addHtmlContent($content);
+ self::assertEquals(
+ 'Foo',
+ $crawler->filterXPath('//h1')->text(),
+ '->addHtmlContent() parses valid HTML with comment before doctype'
+ );
+ }
+
+ /** @dataProvider invalidHtml5Provider */
+ public function testHtml5ParserWithInvalidHeadedContent(string $content): void
+ {
+ $this->skipTestIfHTML5LibraryNotAvailable();
+
+ $crawler = $this->createCrawler();
+ $crawler->addHtmlContent($content);
+ self::assertEmpty($crawler->filterXPath('//h1')->text(), '->addHtmlContent failed as expected');
+ }
+
+ public function validHtml5Provider(): iterable
+ {
+ $html = $this->getDoctype().'Foo
';
+ $BOM = \chr(0xEF).\chr(0xBB).\chr(0xBF);
+
+ yield 'BOM first' => [$BOM.$html];
+ yield 'Single comment' => [''.$html];
+ yield 'Multiline comment' => ["".$html];
+ yield 'Several comments' => [' '.$html];
+ yield 'Whitespaces' => [' '.$html];
+ yield 'All together' => [$BOM.' '.''.$html];
+ }
+
+ public function invalidHtml5Provider(): iterable
+ {
+ $html = $this->getDoctype().'Foo
';
+
+ yield 'Text' => ['hello world'.$html];
+ yield 'Text between comments' => [' test '.$html];
+ }
+
+ private function skipTestIfHTML5LibraryNotAvailable(): void
+ {
+ if (!class_exists(\Masterminds\HTML5::class)) {
+ self::markTestSkipped('HTML5 library is not available');
+ }
+ }
}