Add "repeat" helper

src/Helpers.php

@@ -38,5 +38,6 @@ class Helpers extends BaseHelpers
         // String helpers
         $this->add('lowercase', new String\LowercaseHelper());
         $this->add('uppercase', new String\UppercaseHelper());
+        $this->add('repeat', new String\RepeatHelper());
     }
 }

src/String/Helpers.php

@@ -28,5 +28,6 @@ class Helpers extends BaseHelpers
 
         $this->add('lowercase', new LowercaseHelper());
         $this->add('uppercase', new UppercaseHelper());
+        $this->add('repeat', new RepeatHelper());
     }
 }

src/String/RepeatHelper.php

@@ -0,0 +1,55 @@
+<?php
+/*
+ * This file is part of Handlebars.php Helpers Set
+ *
+ * (c) Dmitriy Simushev <simushevds@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace JustBlackBird\HandlebarsHelpers\String;
+
+use Handlebars\Context;
+use Handlebars\Helper as HelperInterface;
+use Handlebars\Template;
+
+/**
+ * Repeats content specified number of times.
+ *
+ * Usage:
+ * ```handlebars
+ *   {{#repeat times}}content to repeat{{/repeat}}
+ * ```
+ *
+ * Arguments:
+ *  - "times": How many times content must be repeated. This value must be
+ *    greater than or equal to 0 otherwise an exception will be thrown.
+ *
+ * @author Dmitriy Simushev <simushevds@gmail.com>
+ */
+class RepeatHelper implements HelperInterface
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function execute(Template $template, Context $context, $args, $source)
+    {
+        $parsed_args = $template->parseArguments($args);
+        if (count($parsed_args) != 1) {
+            throw new \InvalidArgumentException(
+                '"repeat" helper expects exactly one argument.'
+            );
+        }
+
+        $times = intval($context->get($parsed_args[0]));
+        if ($times < 0) {
+            throw new \InvalidArgumentException(
+                'The first argument has to be greater than or equal to 0.'
+            );
+        }
+        $string = $template->render($context);
+
+        return str_repeat($string, $times);
+    }
+}

tests/HelpersTest.php

@@ -50,6 +50,7 @@ class HelpersTest extends \PHPUnit_Framework_TestCase
             // String helpers
             array('lowercase', '\\JustBlackBird\\HandlebarsHelpers\\String\\LowercaseHelper'),
             array('uppercase', '\\JustBlackBird\\HandlebarsHelpers\\String\\UppercaseHelper'),
+            array('repeat', '\\JustBlackBird\\HandlebarsHelpers\\String\\RepeatHelper'),
         );
     }
 }

tests/String/HelpersTest.php

@@ -40,6 +40,7 @@ class HelpersTest extends \PHPUnit_Framework_TestCase
         return array(
             array('lowercase', '\\JustBlackBird\\HandlebarsHelpers\\String\\LowercaseHelper'),
             array('uppercase', '\\JustBlackBird\\HandlebarsHelpers\\String\\UppercaseHelper'),
+            array('repeat', '\\JustBlackBird\\HandlebarsHelpers\\String\\RepeatHelper'),
         );
     }
 }

tests/String/RepeatHelperTest.php

@@ -0,0 +1,92 @@
+<?php
+/*
+ * This file is part of Handlebars.php Helpers Set
+ *
+ * (c) Dmitriy Simushev <simushevds@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace JustBlackBird\HandlebarsHelpers\Tests\String;
+
+use JustBlackBird\HandlebarsHelpers\String\RepeatHelper;
+
+/**
+ * Test class for "repeat" helper.
+ *
+ * @author Dmitriy Simushev <simushevds@gmail.com>
+ */
+class RepeatHelperTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * Tests that strings are repeated properly.
+     *
+     * @dataProvider repeatProvider
+     */
+    public function testRepeat($string, $times, $result)
+    {
+        $helpers = new \Handlebars\Helpers(array('repeat' => new RepeatHelper()));
+        $engine = new \Handlebars\Handlebars(array('helpers' => $helpers));
+
+        $this->assertEquals(
+            $engine->render(
+                '{{#repeat times}}{{str}}{{/repeat}}',
+                array('times' => $times, 'str' => $string)
+            ),
+            $result
+        );
+    }
+
+    /**
+     * A data provider for testRepeat method.
+     */
+    public function repeatProvider()
+    {
+        return array(
+            array('+', 0, ''),
+            array('+', 3, '+++'),
+            array('', 3, ''),
+        );
+    }
+
+    /**
+     * Tests that exception is thrown if wrong number of arguments is used.
+     *
+     * @expectedException InvalidArgumentException
+     * @dataProvider wrongArgumentsSetProvider
+     */
+    public function testArgumentsCount($template)
+    {
+        $helpers = new \Handlebars\Helpers(array('repeat' => new RepeatHelper()));
+        $engine = new \Handlebars\Handlebars(array('helpers' => $helpers));
+
+        $engine->render($template, array());
+    }
+
+    /**
+     * A data provider for testArgumentsCount method.
+     */
+    public function wrongArgumentsSetProvider()
+    {
+        return array(
+            // Not enough arguments
+            array('{{#repeat}}{{/repeat}}'),
+            // Too much arguments
+            array('{{#repeat 10 "ANOTHER ARG"}}{{/repeat}}'),
+        );
+    }
+
+    /**
+     * Tests that exception is thrown if arguments are invalid.
+     *
+     * @expectedException InvalidArgumentException
+     */
+    public function testInvalidArguments()
+    {
+        $helpers = new \Handlebars\Helpers(array('repeat' => new RepeatHelper()));
+        $engine = new \Handlebars\Handlebars(array('helpers' => $helpers));
+
+        $engine->render('{{#repeat -10}}+{{/repeat}}', array());
+    }
+}