Added basic unit test

Author: imbue

composer.json

@@ -34,5 +34,8 @@
     "psr-4": {
       "Tests\\": "tests"
     }
+  },
+  "scripts": {
+    "test": "./vendor/bin/phpunit tests"
   }
 }

phpunit.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<phpunit colors="true"
+         bootstrap="./vendor/autoload.php">
+    <php>
+        <ini name="display_errors" value="stderr"/>
+        <ini name="error_log" value="/dev/null"/>
+    </php>
+    <testsuite name="Unit tests">
+        <directory>.tests/</directory>
+    </testsuite>
+    <filter>
+        <whitelist processUncoveredFilesFromWhitelist="true">
+            <directory suffix=".php">src/</directory>
+        </whitelist>
+    </filter>
+</phpunit>

tests/ApiClientTest.php

@@ -0,0 +1,42 @@
+<?php
+
+namespace Tests\SendCloud;
+
+use GuzzleHttp\Client;
+use GuzzleHttp\ClientInterface;
+use GuzzleHttp\Psr7\Response;
+use PHPUnit\Framework\TestCase;
+use Imbue\SendCloud\SendCloudApiClient;
+
+class ApiClientTest extends TestCase
+{
+    /** @var ClientInterface */
+    private $guzzleClient;
+    /** @var SendCloudApiClient */
+    private $sendCloudApiClient;
+
+    protected function setUp()
+    {
+        parent::setUp();
+        $this->guzzleClient = $this->createMock(Client::class);
+        $this->sendCloudApiClient = new SendCloudApiClient($this->guzzleClient);
+        $this->sendCloudApiClient->setApiAuth('test_api_key', 'test_api_secret');
+    }
+
+    public function testPerformHttpCallReturnsBodyAsObject()
+    {
+        $response = new Response(200, [], '{"object": "parcel"}');
+
+        $this->guzzleClient
+            ->expects($this->once())
+            ->method('send')
+            ->willReturn($response);
+
+        $parsedResponse = $this->sendCloudApiClient->performHttpCall('GET', '');
+
+        $this->assertEquals(
+            (object)['object' => 'parcel'],
+            $parsedResponse
+        );
+    }
+}