Implements a cookie-date parsing utility

@see php-http/client-common#46

Author: aaa2000

CHANGELOG.md

@@ -3,6 +3,10 @@
 
 ## Unreleased
 
+###
+
+- CookieUtil::parseDate to create a date from cookie date string
+
 ## 1.5.0 - 2017-02-14
 
 ### Added

spec/CookieUtilSpec.php

@@ -0,0 +1,60 @@
+<?php
+
+namespace spec\Http\Message;
+
+use PhpSpec\ObjectBehavior;
+
+class CookieUtilSpec extends ObjectBehavior
+{
+    /**
+     *  @dataProvider getCookieStrings
+     */
+    function it_parses_cookie_date_string($cookieDateString)
+    {
+        $this->beConstructedThrough('parseDate', [$cookieDateString]);
+        $this->shouldHaveType(\DateTime::class);
+        $this->getTimestamp()->shouldReturn(1596185377);
+    }
+
+    /**
+     *  @dataProvider getInvalidCookieDateStrings
+     */
+    function it_returns_false_if_cookie_date_string_is_invalid($cookieDateString)
+    {
+        $this->beConstructedThrough('parseDate', [$cookieDateString]);
+        $this->shouldBe(false);
+    }
+
+    /**
+     * Provides examples for valid cookie date string.
+     *
+     * @return array
+     */
+    public function getCookieStrings()
+    {
+        return [
+            ['Friday, 31 Jul 20 08:49:37 GMT'],
+            ['Friday, 31-Jul-20 08:49:37 GMT'],
+            ['Fri, 31-Jul-2020 08:49:37 GMT'],
+            ['Fri, 31 Jul 2020 08:49:37 GMT'],
+            ['Fri, 31-07-2020 08:49:37 GMT'],
+            ['Fri, 31-07-20 08:49:37 GMT'],
+            ['Friday, 31-Jul-20 08:49:37 GMT'],
+            ['Fri Jul 31 08:49:37 2020'],
+            ['Fri Jul 31 08:49:37 2020'],
+            ['Friday July 31st 2020, 08:49:37 GMT'],
+        ];
+    }
+
+    /**
+     * Provides examples for invalid cookie date string.
+     *
+     * @return array
+     */
+    public function getInvalidCookieDateStrings()
+    {
+        return [
+            ['Flursday July 31st 2020, 08:49:37 GMT'],
+        ];
+    }
+}

src/CookieUtil.php

@@ -0,0 +1,40 @@
+<?php
+
+namespace Http\Message;
+
+final class CookieUtil
+{
+    /**
+     * Handles dates as defined by RFC 2616 section 3.3.1, and also some other
+     * non-standard, but common formats.
+     *
+     * @var array
+     */
+    private static $dateFormats = array(
+        'D, d M y H:i:s T',
+        'D, d M Y H:i:s T',
+        'D, d-M-y H:i:s T',
+        'D, d-M-Y H:i:s T',
+        'D, d-m-y H:i:s T',
+        'D, d-m-Y H:i:s T',
+        'D M j G:i:s Y',
+        'D M d H:i:s Y T',
+    );
+
+    /**
+     * @see https://github.com/symfony/symfony/blob/master/src/Symfony/Component/BrowserKit/Cookie.php
+     *
+     * @param string $dateValue
+     * @return \DateTime|false
+     */
+    public static function parseDate($dateValue)
+    {
+        foreach (self::$dateFormats as $dateFormat) {
+            if (false !== $date = \DateTime::createFromFormat($dateFormat, $dateValue, new \DateTimeZone('GMT'))) {
+                return $date;
+            }
+        }
+        // attempt a fallback for unusual formatting
+        return date_create($dateValue, new \DateTimeZone('GMT'));
+    }
+}