7 regex type (#13)

* Add datetime type

* Update type list in readme

* Add regex type

Author: Christian Blank

README.md

@@ -70,6 +70,7 @@ Currently the following types are supported:
  * Object
  * List
  * Datetime
+ * Regex
 
 There are some open issues with ideas for more types. Feel free to send pull requests.
 

spec/Type/RegexTypeSpec.php

@@ -0,0 +1,42 @@
+<?php
+
+namespace spec\StructureCheck\Type;
+
+use PhpSpec\ObjectBehavior;
+use StructureCheck\Type\RegexType;
+
+class RegexTypeSpec extends ObjectBehavior
+{
+
+    function it_is_initializable()
+    {
+        $this->beConstructedWith('/^def/');
+
+        $this->shouldHaveType(RegexType::class);
+    }
+
+    function it_should_return_valid_for_matching_strings()
+    {
+        $this->beConstructedWith('/^def/');
+
+        $this->check('definitive')->isValid()->shouldBe(true);
+    }
+
+    function it_should_return_invalid_for_not_matching_strings()
+    {
+        $this->beConstructedWith('/^def/');
+
+        $this->check('developers')->isValid()->shouldBe(false);
+    }
+
+    function it_should_return_invalid_for_others()
+    {
+        $this->beConstructedWith('/^def/');
+
+        $this->check(null)->isValid()->shouldBe(false);
+        $this->check(12.3)->isValid()->shouldBe(false);
+        $this->check([])->isValid()->shouldBe(false);
+        $this->check(-1)->isValid()->shouldBe(false);
+        $this->check(true)->isValid()->shouldBe(false);
+    }
+}

src/Type/RegexType.php

@@ -0,0 +1,48 @@
+<?php
+
+namespace StructureCheck\Type;
+
+use StructureCheck\Result;
+use StructureCheck\ResultInterface;
+
+/**
+ * Class RegexType
+ * @package StructureCheck\Type
+ */
+class RegexType
+{
+    /**
+     * @var string
+     */
+    private static $errorMessage = 'The value %s does not match the regex %s';
+
+    /**
+     * @var string
+     */
+    private $regex;
+
+    /**
+     * RegexType constructor.
+     *
+     * @param string $regex
+     */
+    public function __construct($regex)
+    {
+        $this->regex = $regex;
+    }
+
+    /**
+     * @param mixed $value
+     *
+     * @return ResultInterface
+     */
+    public function check($value)
+    {
+        $checkResult = is_string($value) && preg_match($this->regex, $value) === 1;
+
+        return new Result(
+            $checkResult,
+            !$checkResult ? [sprintf(self::$errorMessage, json_encode($value), $this->regex)] : []
+        );
+    }
+}