Fix the :only-of-type pseudo class selector

jakzal · fabpot · commit f819f71ae3ba · 2019-10-01T13:57:37.000+02:00
diff --git a/Tests/XPath/TranslatorTest.php b/Tests/XPath/TranslatorTest.php
@@ -98,7 +98,7 @@ public function testXmlLang($css, array $elementsId)
         $elements = $document->xpath($translator->cssToXPath($css));
         $this->assertCount(\count($elementsId), $elements);
         foreach ($elements as $element) {
-            $this->assertTrue(\in_array($element->attributes()->id, $elementsId));
+            $this->assertContains((string) $element->attributes()->id, $elementsId);
         }
     }
 
@@ -116,7 +116,7 @@ public function testHtmlIds($css, array $elementsId)
         $this->assertCount(\count($elementsId), $elementsId);
         foreach ($elements as $element) {
             if (null !== $element->attributes()->id) {
-                $this->assertTrue(\in_array($element->attributes()->id, $elementsId));
+                $this->assertContains((string) $element->attributes()->id, $elementsId);
             }
         }
         libxml_clear_errors();
@@ -137,6 +137,33 @@ public function testHtmlShakespear($css, $count)
         $this->assertCount($count, $elements);
     }
 
+    public function testOnlyOfTypeFindsSingleChildrenOfGivenType()
+    {
+        $translator = new Translator();
+        $translator->registerExtension(new HtmlExtension($translator));
+        $document = new \DOMDocument();
+        $document->loadHTML(<<<'HTML'
+<html>
+  <body>
+    <p>
+      <span>A</span>
+    </p>
+    <p>
+      <span>B</span>
+      <span>C</span>
+    </p>
+  </body>
+</html>
+HTML
+);
+
+        $xpath = new \DOMXPath($document);
+        $nodeList = $xpath->query($translator->cssToXPath('span:only-of-type'));
+
+        $this->assertSame(1, $nodeList->length);
+        $this->assertSame('A', $nodeList->item(0)->textContent);
+    }
+
     public function getXpathLiteralTestData()
     {
         return [
@@ -175,7 +202,7 @@ public function getCssToXPathTestData()
             ['e:first-of-type', '*/e[position() = 1]'],
             ['e:last-of-type', '*/e[position() = last()]'],
             ['e:only-child', "*/*[(name() = 'e') and (last() = 1)]"],
-            ['e:only-of-type', 'e[last() = 1]'],
+            ['e:only-of-type', 'e[count(preceding-sibling::e)=0 and count(following-sibling::e)=0]'],
             ['e:empty', 'e[not(*) and not(string-length())]'],
             ['e:EmPTY', 'e[not(*) and not(string-length())]'],
             ['e:root', 'e[not(parent::*)]'],
diff --git a/XPath/Extension/PseudoClassExtension.php b/XPath/Extension/PseudoClassExtension.php
@@ -123,11 +123,13 @@ public function translateOnlyChild(XPathExpr $xpath)
      */
     public function translateOnlyOfType(XPathExpr $xpath)
     {
-        if ('*' === $xpath->getElement()) {
+        $element = $xpath->getElement();
+
+        if ('*' === $element) {
             throw new ExpressionErrorException('"*:only-of-type" is not implemented.');
         }
 
-        return $xpath->addCondition('last() = 1');
+        return $xpath->addCondition(sprintf('count(preceding-sibling::%s)=0 and count(following-sibling::%s)=0', $element, $element));
     }
 
     /**

Original file line number	Diff line number	Diff line change
`@@ -123,11 +123,13 @@ public function translateOnlyChild(XPathExpr $xpath)`
`123`	`123`	`*/`
`124`	`124`	`public function translateOnlyOfType(XPathExpr $xpath)`
`125`	`125`	`{`
`126`		`- if ('*' === $xpath->getElement()) {`
	`126`	`+ $element = $xpath->getElement();`
	`127`	`+`
	`128`	`+ if ('*' === $element) {`
`127`	`129`	`throw new ExpressionErrorException('"*:only-of-type" is not implemented.');`
`128`	`130`	`}`
`129`	`131`
`130`		`- return $xpath->addCondition('last() = 1');`
	`132`	`+ return $xpath->addCondition(sprintf('count(preceding-sibling::%s)=0 and count(following-sibling::%s)=0', $element, $element));`
`131`	`133`	`}`
`132`	`134`
`133`	`135`	`/**`