[TASK] Always calculate selector specificity on demand

This avoids additional state that makes it hard to compare
selectors for equality.

Also, this will improve performance for cases where the
specificity is not needed (but will slightly worsen
performance where the specificity is queried multiple times
on the same selector instance).

Closes #1021

Author: oliverklee

src/Property/Selector.php

@@ -72,11 +72,6 @@ class Selector implements Renderable
      */
     private $selector;
 
-    /**
-     * @var int|null
-     */
-    private $specificity;
-
     /**
      * @return bool
      *
@@ -87,15 +82,9 @@ public static function isValid(string $selector)
         return \preg_match(static::SELECTOR_VALIDATION_RX, $selector);
     }
 
-    /**
-     * @param bool $calculateSpecificity @deprecated since V8.8.0, will be removed in V9.0.0
-     */
-    public function __construct(string $selector, bool $calculateSpecificity = false)
+    public function __construct(string $selector)
     {
         $this->setSelector($selector);
-        if ($calculateSpecificity) {
-            $this->getSpecificity();
-        }
     }
 
     public function getSelector(): string
@@ -106,7 +95,6 @@ public function getSelector(): string
     public function setSelector(string $selector): void
     {
         $this->selector = \trim($selector);
-        $this->specificity = null;
     }
 
     /**
@@ -122,16 +110,14 @@ public function __toString(): string
      */
     public function getSpecificity(): int
     {
-        if ($this->specificity === null) {
-            $a = 0;
-            /// @todo should exclude \# as well as "#"
-            $aMatches = null;
-            $b = \substr_count($this->selector, '#');
-            $c = \preg_match_all(self::NON_ID_ATTRIBUTES_AND_PSEUDO_CLASSES_RX, $this->selector, $aMatches);
-            $d = \preg_match_all(self::ELEMENTS_AND_PSEUDO_ELEMENTS_RX, $this->selector, $aMatches);
-            $this->specificity = ($a * 1000) + ($b * 100) + ($c * 10) + $d;
-        }
-        return $this->specificity;
+        $a = 0;
+        // @todo should exclude \# as well as "#"
+        $aMatches = null;
+        $b = \substr_count($this->selector, '#');
+        $c = \preg_match_all(self::NON_ID_ATTRIBUTES_AND_PSEUDO_CLASSES_RX, $this->selector, $aMatches);
+        $d = \preg_match_all(self::ELEMENTS_AND_PSEUDO_ELEMENTS_RX, $this->selector, $aMatches);
+
+        return ($a * 1000) + ($b * 100) + ($c * 10) + $d;
     }
 
     public function render(OutputFormat $outputFormat): string

tests/ParserTest.php

@@ -246,26 +246,26 @@ public function unicodeRangeParsing(): void
     public function specificity(): void
     {
         $document = self::parsedStructureForFile('specificity');
-        self::assertEquals([new Selector('#test .help', true)], $document->getSelectorsBySpecificity('> 100'));
+        self::assertEquals([new Selector('#test .help')], $document->getSelectorsBySpecificity('> 100'));
         self::assertEquals(
-            [new Selector('#test .help', true), new Selector('#file', true)],
+            [new Selector('#test .help'), new Selector('#file')],
             $document->getSelectorsBySpecificity('>= 100')
         );
-        self::assertEquals([new Selector('#file', true)], $document->getSelectorsBySpecificity('=== 100'));
-        self::assertEquals([new Selector('#file', true)], $document->getSelectorsBySpecificity('== 100'));
+        self::assertEquals([new Selector('#file')], $document->getSelectorsBySpecificity('=== 100'));
+        self::assertEquals([new Selector('#file')], $document->getSelectorsBySpecificity('== 100'));
         self::assertEquals([
-            new Selector('#file', true),
-            new Selector('.help:hover', true),
-            new Selector('li.green', true),
-            new Selector('ol li::before', true),
+            new Selector('#file'),
+            new Selector('.help:hover'),
+            new Selector('li.green'),
+            new Selector('ol li::before'),
         ], $document->getSelectorsBySpecificity('<= 100'));
         self::assertEquals([
-            new Selector('.help:hover', true),
-            new Selector('li.green', true),
-            new Selector('ol li::before', true),
+            new Selector('.help:hover'),
+            new Selector('li.green'),
+            new Selector('ol li::before'),
         ], $document->getSelectorsBySpecificity('< 100'));
-        self::assertEquals([new Selector('li.green', true)], $document->getSelectorsBySpecificity('11'));
-        self::assertEquals([new Selector('ol li::before', true)], $document->getSelectorsBySpecificity('3'));
+        self::assertEquals([new Selector('li.green')], $document->getSelectorsBySpecificity('11'));
+        self::assertEquals([new Selector('ol li::before')], $document->getSelectorsBySpecificity('3'));
     }
 
     /**