Add "uppercase" helper

src/Helpers.php

@@ -37,5 +37,6 @@ class Helpers extends BaseHelpers
 
         // String helpers
         $this->add('lowercase', new String\LowercaseHelper());
+        $this->add('uppercase', new String\UppercaseHelper());
     }
 }

src/String/Helpers.php

@@ -27,5 +27,6 @@ class Helpers extends BaseHelpers
         parent::addDefaultHelpers();
 
         $this->add('lowercase', new LowercaseHelper());
+        $this->add('uppercase', new UppercaseHelper());
     }
 }

src/String/UppercaseHelper.php

@@ -0,0 +1,46 @@
+<?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;
+
+/**
+ * Converts a string to uppercase.
+ *
+ * Usage:
+ * ```handlebars
+ *   {{uppercase string}}
+ * ```
+ *
+ * Arguments:
+ *  - "string": A string that should be converted to uppercase.
+ *
+ * @author Dmitriy Simushev <simushevds@gmail.com>
+ */
+class UppercaseHelper implements HelperInterface
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function execute(Template $template, Context $context, $args, $source)
+    {
+        $parsed_args = $template->parseArguments($args);
+        if (count($parsed_args) != 1) {
+            throw new \InvalidArgumentException(
+                '"uppercase" helper expects exactly one argument.'
+            );
+        }
+
+        return strtoupper($context->get($parsed_args[0]));
+    }
+}

tests/HelpersTest.php

@@ -49,6 +49,7 @@ class HelpersTest extends \PHPUnit_Framework_TestCase
 
             // String helpers
             array('lowercase', '\\JustBlackBird\\HandlebarsHelpers\\String\\LowercaseHelper'),
+            array('uppercase', '\\JustBlackBird\\HandlebarsHelpers\\String\\UppercaseHelper'),
         );
     }
 }

tests/String/HelpersTest.php

@@ -39,6 +39,7 @@ class HelpersTest extends \PHPUnit_Framework_TestCase
     {
         return array(
             array('lowercase', '\\JustBlackBird\\HandlebarsHelpers\\String\\LowercaseHelper'),
+            array('uppercase', '\\JustBlackBird\\HandlebarsHelpers\\String\\UppercaseHelper'),
         );
     }
 }

tests/String/UppercaseHelperTest.php

@@ -0,0 +1,80 @@
+<?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\UppercaseHelper;
+
+/**
+ * Test class for "uppercase" helper.
+ *
+ * @author Dmitriy Simushev <simushevds@gmail.com>
+ */
+class UppercaseHelperTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * Tests that strings are converted to uppercase properly.
+     *
+     * @dataProvider convertProvider
+     */
+    public function testConvert($string, $result)
+    {
+        $helpers = new \Handlebars\Helpers(array('uppercase' => new UppercaseHelper()));
+        $engine = new \Handlebars\Handlebars(array('helpers' => $helpers));
+
+        $this->assertEquals(
+            $engine->render(
+                '{{uppercase str}}',
+                array('str' => $string)
+            ),
+            $result
+        );
+    }
+
+    /**
+     * A data provider for testConvert method.
+     */
+    public function convertProvider()
+    {
+        return array(
+            array('ALREADY IN UPPERCASE', 'ALREADY IN UPPERCASE'),
+            array('Mixed Case String', 'MIXED CASE STRING'),
+            array('ANOther mIxed CASE string', 'ANOTHER MIXED CASE STRING'),
+            array('string in lowercase', 'STRING IN LOWERCASE'),
+        );
+    }
+
+    /**
+     * Tests that exception is thrown if wrong number of arguments is used.
+     *
+     * @expectedException InvalidArgumentException
+     * @dataProvider wrongArgumentsProvider
+     */
+    public function testArgumentsCount($template)
+    {
+        $helpers = new \Handlebars\Helpers(array('uppercase' => new UppercaseHelper()));
+        $engine = new \Handlebars\Handlebars(array('helpers' => $helpers));
+
+        $engine->render($template, array());
+    }
+
+    /**
+     * A data provider for testArgumentsCount method.
+     */
+    public function wrongArgumentsProvider()
+    {
+        return array(
+            // Not enough arguments
+            array('{{uppercase}}'),
+            // Too much arguments
+            array('{{uppercase "Arg" "ANOTHER ARG"}}'),
+        );
+    }
+}