Support PSR-18

Author: Nyholm

composer.json

@@ -11,21 +11,22 @@
         }
     ],
     "prefer-stable": true,
-    "minimum-stability": "beta",
+    "minimum-stability": "dev",
     "config": {
         "bin-dir": "vendor/bin"
     },
     "require": {
-        "php": "^5.5 || ^7.0",
+        "php": "^7.1",
         "ext-curl": "*",
-        "php-http/httplug": "^1.0",
+        "psr/http-client": "^0.3",
+        "php-http/httplug": "^2.0",
         "php-http/message-factory": "^1.0.2",
         "php-http/message": "^1.2",
         "php-http/discovery": "^1.0"
     },
     "require-dev": {
         "guzzlehttp/psr7": "^1.0",
-        "php-http/client-integration-tests": "^0.6",
+        "php-http/client-integration-tests": "dev-master",
         "phpunit/phpunit": "^4.8.27",
         "zendframework/zend-diactoros": "^1.0"
     },

src/Client.php

@@ -10,6 +10,7 @@
 use Http\Message\MessageFactory;
 use Http\Message\StreamFactory;
 use Http\Promise\Promise;
+use Psr\Http\Client\ClientInterface;
 use Psr\Http\Message\RequestInterface;
 use Psr\Http\Message\ResponseInterface;
 
@@ -24,7 +25,7 @@
  *
  * @since   1.0
  */
-class Client implements HttpClient, HttpAsyncClient
+class Client implements HttpClient, HttpAsyncClient, ClientInterface
 {
     /**
      * cURL options.
@@ -108,7 +109,7 @@ public function __destruct()
      * @since 1.6 Throw NetworkException on network errors
      * @since 1.0
      */
-    public function sendRequest(RequestInterface $request)
+    public function sendRequest(RequestInterface $request): ResponseInterface
     {
         $responseBuilder = $this->createResponseBuilder();
         $options = $this->createCurlOptions($request, $responseBuilder);