add unit testing and using Guzzle

.editorconfig

@@ -0,0 +1,9 @@
+root = true
+
+[*]
+end_of_line = lf
+insert_final_newline = true
+
+[composer.json]
+indent_style = space
+indent_size = 4

.travis.yml

@@ -0,0 +1,43 @@
+language: php
+
+php:
+  - 5.6
+  - 7.0
+  - nightly
+
+sudo: false
+
+env:
+  global:
+    - PATH="$HOME/.composer/vendor/bin:$PATH"
+
+cache:
+  directories:
+    - $HOME/.composer/cache
+
+matrix:
+  fast_finish: true
+  include:
+    - php: 5.6
+      env: COMPOSER_FLAGS="--prefer-lowest"
+  allow_failures:
+    - php: nightly
+
+before_install:
+  - phpenv global 5.6
+
+install:
+  - mkdir -p ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d && echo "memory_limit=-1" >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini
+  - mkdir -p build/logs
+  - composer global require satooshi/php-coveralls:@stable --no-update
+  - composer global update --prefer-dist --no-interaction
+  - composer update --prefer-dist --no-interaction $COMPOSER_FLAGS
+
+before_script:
+  - composer require phpunit/phpunit
+
+script:
+  - vendor/bin/phpunit
+
+after_script:
+  - coveralls -v

composer.json

@@ -11,8 +11,8 @@
 		}
 	],
 	"require": {
-		"php": ">=5.2.2",
-		"ext-simplexml": "*"
+		"php": ">=5.6",
+		"guzzlehttp/guzzle": "^6.2"
 	},
 	"autoload": {
 		"classmap": ["src/"]

phpunit.xml.dist

@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<phpunit
+    colors="true"
+    bootstrap="./vendor/autoload.php"
+    charset="UTF-8">
+
+    <testsuites>
+        <testsuite name="Testing Suite">
+      	    <directory suffix=".php">./tests/</directory>
+        </testsuite>
+    </testsuites>
+
+    <filter>
+        <whitelist>
+            <directory>./src/</directory>
+        </whitelist>
+    </filter>
+
+    <logging>
+        <log type="coverage-clover" target="build/logs/clover.xml"/>
+        <log type="coverage-html" target="result/" />
+    </logging>
+
+</phpunit>

src/Feed.php

@@ -7,6 +7,11 @@
  * @license    New BSD License
  * @version    1.3
  */
+
+use GuzzleHttp\Client;
+use GuzzleHttp\Exception\ClientException;
+use Psr\Http\Message\ResponseInterface;
+
 class Feed
 {
 	/** @var int */
@@ -202,30 +207,14 @@ private static function loadXml($url, $user, $pass)
 	 */
 	private static function httpRequest($url, $user, $pass)
 	{
-		if (extension_loaded('curl')) {
-			$curl = curl_init();
-			curl_setopt($curl, CURLOPT_URL, $url);
-			if ($user !== null || $pass !== null) {
-				curl_setopt($curl, CURLOPT_USERPWD, "$user:$pass");
-			}
-			curl_setopt($curl, CURLOPT_HEADER, false);
-			curl_setopt($curl, CURLOPT_TIMEOUT, 20);
-			curl_setopt($curl, CURLOPT_ENCODING, '');
-			curl_setopt($curl, CURLOPT_RETURNTRANSFER, true); // no echo, just return result
-			if (!ini_get('open_basedir')) {
-				curl_setopt($curl, CURLOPT_FOLLOWLOCATION, true); // sometime is useful :)
-			}
-			$result = curl_exec($curl);
-			return curl_errno($curl) === 0 && curl_getinfo($curl, CURLINFO_HTTP_CODE) === 200
-				? $result
-				: false;
-
-		} elseif ($user === null && $pass === null) {
-			return file_get_contents($url);
-
-		} else {
-			throw new FeedException('PHP extension CURL is not loaded.');
+		$client = new Client();
+		$requestOptions['verify'] =  __DIR__ . '/cacert.pem';
+		if($user !== NULL && $pass !== NULL) {
+			$requestOptions['auth'] = [$user, $pass];
 		}
+		$response = $client->request('GET', $url, $requestOptions);
+
+		return $response->getBody()->getContents();
 	}