[CssSelector] Added cache on top of CssSelectorConverter

Author: lyrixx

CssSelectorConverter.php

@@ -27,6 +27,10 @@
 class CssSelectorConverter
 {
     private $translator;
+    private $cache;
+
+    private static $xmlCache = [];
+    private static $htmlCache = [];
 
     /**
      * @param bool $html Whether HTML support should be enabled. Disable it for XML documents
@@ -37,6 +41,9 @@ public function __construct(bool $html = true)
 
         if ($html) {
             $this->translator->registerExtension(new HtmlExtension($this->translator));
+            $this->cache = &self::$htmlCache;
+        } else {
+            $this->cache = &self::$xmlCache;
         }
 
         $this->translator
@@ -57,6 +64,6 @@ public function __construct(bool $html = true)
      */
     public function toXPath(string $cssExpr, string $prefix = 'descendant-or-self::')
     {
-        return $this->translator->cssToXPath($cssExpr, $prefix);
+        return $this->cache[$prefix][$cssExpr] ?? $this->cache[$prefix][$cssExpr] = $this->translator->cssToXPath($cssExpr, $prefix);
     }
 }

Tests/CssSelectorConverterTest.php

@@ -26,13 +26,21 @@ public function testCssToXPath()
         $this->assertEquals("descendant-or-self::h1[@class and contains(concat(' ', normalize-space(@class), ' '), ' foo ')]", $converter->toXPath('h1.foo'));
         $this->assertEquals('descendant-or-self::foo:h1', $converter->toXPath('foo|h1'));
         $this->assertEquals('descendant-or-self::h1', $converter->toXPath('H1'));
+
+        // Test the cache layer
+        $converter = new CssSelectorConverter();
+        $this->assertEquals('descendant-or-self::h1', $converter->toXPath('H1'));
     }
 
     public function testCssToXPathXml()
     {
         $converter = new CssSelectorConverter(false);
 
         $this->assertEquals('descendant-or-self::H1', $converter->toXPath('H1'));
+
+        $converter = new CssSelectorConverter(false);
+        // Test the cache layer
+        $this->assertEquals('descendant-or-self::H1', $converter->toXPath('H1'));
     }
 
     public function testParseExceptions()