finished string::encoding test.

tests/cases/laravel/str.test.php

+<?php
+
+class StrTest extends PHPUnit_Framework_TestCase {
+
+	/**
+	 * Test the Str::encoding method.
+	 *
+	 * @group laravel
+	 */
+	public function testEncodingShouldReturnApplicationEncoding()
+	{
+		$this->assertEquals('UTF-8', Config::get('application.encoding'));
+		Config::set('application.encoding', 'foo');
+		$this->assertEquals('foo', Config::get('application.encoding'));
+		Config::set('application.encoding', 'UTF-8');
+	}
+
+}
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