add method for checking a file's age

Author: sebastianheuer

src/Filename.php

@@ -109,6 +109,22 @@ public function delete() {
         return unlink($this->asString());
     }
 
+    /**
+     * @param \DateTimeImmutable $date
+     * @return bool
+     */
+    public function isOlderThan(\DateTimeImmutable $date) {
+        return $this->getLastModified()->isOlderThan($date);
+    }
+
+    /**
+     * @return LastModifiedDate
+     * @throws FilenameException
+     */
+    private function getLastModified() {
+        return LastModifiedDate::fromTimestamp(filemtime($this->asString()));
+    }
+
     /**
      * @return string
      */

src/FilenameException.php

@@ -0,0 +1,5 @@
+<?php
+namespace PharIo\FileSystem;
+
+class FilenameException extends Exception {
+}

src/LastModifiedDate.php

@@ -0,0 +1,38 @@
+<?php
+namespace PharIo\FileSystem;
+
+class LastModifiedDate {
+    /**
+     * @var \DateTimeImmutable
+     */
+    private $dateTime;
+
+    /**
+     * @param \DateTimeImmutable $dateTime
+     */
+    public function __construct(\DateTimeImmutable $dateTime) {
+        $this->dateTime = $dateTime;
+    }
+
+    /**
+     * @param int $timestamp
+     * @throws FilenameException
+     * @return LastModifiedDate
+     */
+    public static function fromTimestamp($timestamp) {
+        $dateTime = \DateTimeImmutable::createFromFormat('U', $timestamp);
+        if (false === $dateTime) {
+            throw new FilenameException('Invalid last modified date');
+        }
+
+        return new self($dateTime);
+    }
+
+    /**
+     * @param \DateTimeImmutable $date
+     * @return bool
+     */
+    public function isOlderThan(\DateTimeImmutable $date) {
+        return $this->dateTime < $date;
+    }
+}

tests/LastModifiedDateTest.php

@@ -0,0 +1,47 @@
+<?php
+namespace PharIo\FileSystem;
+
+use PHPUnit\Framework\TestCase;
+
+/**
+ * @covers \PharIo\FileSystem\LastModifiedDate
+ */
+class LastModifiedDateTest extends TestCase
+{
+    public function testCreatesInstanceFromTimestamp() {
+        $expected = new LastModifiedDate(
+            new \DateTimeImmutable('25.04.2017 10:31:55')
+        );
+
+        $actual = LastModifiedDate::fromTimestamp(1493116315);
+
+        $this->assertEquals($expected, $actual);
+    }
+
+    /**
+     * @dataProvider isOlderTestProvider
+     *
+     * @param string $fileTime
+     * @param string $olderThan
+     * @param bool $expectedReturnValue
+     */
+    public function testIsOlderThanReturnsExpectedValue(
+        $fileTime, $olderThan, $expectedReturnValue
+    ) {
+        $date = new LastModifiedDate(new \DateTimeImmutable($fileTime));
+
+        $this->assertSame($expectedReturnValue, $date->isOlderThan(new \DateTimeImmutable($olderThan)));
+    }
+
+    /**
+     * @return array
+     */
+    public function isOlderTestProvider() {
+        return [
+            ['25.04.2017 12:23:12', '25.04.2017 10:12:00', false],
+            ['23.04.2017 12:23:12', '25.04.2017 23:12:00', true],
+            ['23.04.2015 12:23:12', '25.04.2017 23:12:00', true]
+        ];
+    }
+
+}