Added some basic tests

tests/StyleTest.php

@@ -0,0 +1,57 @@
+<?php
+
+namespace Test;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Console\Input\ArgvInput;
+use Symfony\Component\Console\Output\StreamOutput;
+use Symfony\Component\Console\Helper\FormatterHelper;
+use Symfony\Component\Console\Tester\TesterTrait;
+use BlueConsole\Style;
+
+class StyleTest extends TestCase
+{
+    use TesterTrait;
+
+    /**
+     * @var Style
+     */
+    protected $style;
+
+    /**
+     * @var StreamOutput
+     */
+    private $output;
+
+    public function setUp()
+    {
+        $input = new ArgvInput;
+        $this->output = new StreamOutput(fopen('php://memory', 'w+', false));
+        $formatter = new FormatterHelper;
+        $this->style = new Style($input, $this->output, $formatter);
+    }
+
+    public function testWarningMessage()
+    {
+        $this->style->warningMessage('Warning message');
+        $this->assertEquals($this->getDisplay(), "[WARNING]            Warning message\n");
+    }
+
+    public function testErrorMessage()
+    {
+        $this->style->errorMessage('Error message');
+        $this->assertEquals($this->getDisplay(), "[ERROR]              Error message\n");
+    }
+
+    public function testOkMessage()
+    {
+        $this->style->okMessage('Ok message');
+        $this->assertEquals($this->getDisplay(), "[OK]                 Ok message\n");
+    }
+
+    public function testInfoMessage()
+    {
+        $this->style->infoMessage('Info message');
+        $this->assertEquals($this->getDisplay(), "[INFO]               Info message\n");
+    }
+}