release: v3.1.0 premium smart core engines and 14 new accessibility rules

src/Rules/ScrollableRegionFocusable.php

@@ -0,0 +1,33 @@
+<?php
+
+namespace YakNet\AccessibilityConsole\Rules;
+
+use DOMElement;
+use YakNet\AccessibilityConsole\Core\Severity;
+use YakNet\AccessibilityConsole\Core\Violation;
+use YakNet\AccessibilityConsole\Core\WCAGStandard;
+
+class ScrollableRegionFocusable extends AbstractRule
+{
+    public function getId(): string { return 'WCAG_2_1_1_SCROLLABLE_FOCUS'; }
+    public function getDescription(): string { return 'Scrollable regions must be focusable via keyboard using tabindex="0".'; }
+    public function getStandard(): WCAGStandard { return WCAGStandard::A; }
+    public function getSeverity(): Severity { return Severity::ERROR; }
+    public function getLevel(): int { return 3; }
+
+    public function check(DOMElement $element): ?Violation
+    {
+        $style = $element->getAttribute('style');
+        if ($style && preg_match('/overflow(-x|-y)?\s*:\s*(scroll|auto)/i', $style)) {
+            if (!$element->hasAttribute('tabindex') || (int)$element->getAttribute('tabindex') < 0) {
+                return $this->createViolation(
+                    $element,
+                    $this->getDescription(),
+                    'Add tabindex="0" to the scrollable element so keyboard users can navigate to and scroll it.'
+                );
+            }
+        }
+
+        return null;
+    }
+}