Add ifBetween helper

src/Comparison/Helpers.php

@@ -32,6 +32,7 @@ class Helpers extends BaseHelpers
         $this->add('ifOdd', new IfOddHelper());
         $this->add('ifLess', new IfLessHelper());
         $this->add('ifMore', new IfMoreHelper());
+        $this->add('ifBetween', new IfBetweenHelper());
         $this->add('unlessEqual', new UnlessEqualHelper());
     }
 }

src/Comparison/IfBetweenHelper.php

@@ -0,0 +1,48 @@
+<?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\Comparison;
+
+use Handlebars\Helper as HelperInterface;
+
+/**
+ * Conditional helper that checks if one value is between two another values.
+ *
+ * Borders of the interval are excluded from comparison. That's why in cases
+ * where the value under comparision is equal to one of the borders the result of
+ * "between" operator is false.
+ *
+ * Example of usage:
+ * ```handlebars
+ *   {{#ifBetween value leftBorder rightBorder}
+ *     The first argument is between borders.
+ *   {{else}}
+ *     The first argument is not between the borders.
+ *   {{/ifBetween}}
+ * ```
+ *
+ * @author Dmitriy Simushev <simushevds@gmail.com>
+ */
+class IfBetweenHelper extends AbstractComparisonHelper implements HelperInterface
+{
+    /**
+     * {@inheritdoc}
+     */
+    protected function evaluateCondition($args)
+    {
+        if (count($args) != 3) {
+            throw new \InvalidArgumentException(
+                '"ifBetween" helper expects exactly three arguments.'
+            );
+        }
+
+        return ($args[0] > $args[1]) && ($args[0] < $args[2]);
+    }
+}

tests/Comparison/HelpersTest.php

@@ -44,6 +44,7 @@ class HelpersTest extends \PHPUnit_Framework_TestCase
             array('ifOdd', '\\JustBlackBird\\HandlebarsHelpers\\Comparison\\IfOddHelper'),
             array('ifLess', '\\JustBlackBird\\HandlebarsHelpers\\Comparison\\IfLessHelper'),
             array('ifMore', '\\JustBlackBird\\HandlebarsHelpers\\Comparison\\IfMoreHelper'),
+            array('ifBetween', '\\JustBlackBird\\HandlebarsHelpers\\Comparison\\IfBetweenHelper'),
             array('unlessEqual', '\\JustBlackBird\\HandlebarsHelpers\\Comparison\\UnlessEqualHelper'),
         );
     }

tests/Comparison/IfBetweenHelperTest.php

@@ -0,0 +1,93 @@
+<?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\Comparison;
+
+use JustBlackBird\HandlebarsHelpers\Comparison\IfBetweenHelper;
+
+/**
+ * Test class for "ifBetween" helper.
+ *
+ * @author Dmitriy Simushev <simushevds@gmail.com>
+ */
+class IfBetweenHelperTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * Tests conditions work as expected.
+     *
+     * @dataProvider conditionProvider
+     */
+    public function testCondition($value, $left, $right, $is_between)
+    {
+        $helpers = new \Handlebars\Helpers(array('ifBetween' => new IfBetweenHelper()));
+        $engine = new \Handlebars\Handlebars(array('helpers' => $helpers));
+
+        $this->assertEquals(
+            $engine->render(
+                '{{#ifBetween value left right}}true{{else}}false{{/ifBetween}}',
+                array(
+                    'value' => $value,
+                    'left' => $left,
+                    'right' => $right,
+                )
+            ),
+            $is_between ? 'true' : 'false'
+        );
+    }
+
+    /**
+     * A data provider for testCondition method.
+     */
+    public function conditionProvider()
+    {
+        return array(
+            // The value is less than left border.
+            array(2, 10, 12, false),
+            // The value equals to the left border.
+            array(0, 0, 42, false),
+            // The value equals to the right border.
+            array(9, 0, 9, false),
+            // The value is more than the right border.
+            array(75, 10, 12, false),
+            // The value is between borders.
+            array(58, 11, 134, true),
+        );
+    }
+
+    /**
+     * Tests that exception is thrown if wrong number of arguments is used.
+     *
+     * @expectedException InvalidArgumentException
+     * @dataProvider wrongArgumentsProvider
+     */
+    public function testArgumentsCount($template)
+    {
+        $helpers = new \Handlebars\Helpers(array('ifBetween' => new IfBetweenHelper()));
+        $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('{{#ifBetween}}yes{{else}}no{{/ifBetween}}'),
+            // Still not enough arguments
+            array('{{#ifBetween 1}}yes{{else}}no{{/ifBetween}}'),
+            array('{{#ifBetween 1 2}}yes{{else}}no{{/ifBetween}}'),
+            // Too much arguments
+            array('{{#ifBetween 1 2 3 4}}yes{{else}}no{{/ifBetween}}'),
+        );
+    }
+}