Render form input and textarea styles on frontend

[MAILPOET-2599]

tests/unit/Form/TextInputStylesRendererTest.php

@@ -0,0 +1,43 @@
+<?php
+
+namespace MailPoet\Test\Form;
+
+use MailPoet\Form\TextInputStylesRenderer;
+
+require_once __DIR__ . '/HtmlParser.php';
+
+class TextInputStylesRendererTest extends \MailPoetUnitTest {
+  /** @var TextInputStylesRenderer */
+  private $renderer;
+
+  public function _before() {
+    parent::_before();
+    $this->renderer = new TextInputStylesRenderer();
+  }
+
+  public function testItShouldReturnEmptyStringForNoStylesOrUnsupportedStyles() {
+    expect($this->renderer->render([]))->equals('');
+    expect($this->renderer->render(['nonsense' => '10px']))->equals('');
+  }
+
+  public function testItShouldRenderSingleStyles() {
+    expect($this->renderer->render(['border_radius' => 10]))->equals('border-radius:10px;');
+    expect($this->renderer->render(['border_color' => '#fff']))->equals('border-color:#fff;');
+    expect($this->renderer->render(['border_size' => 10]))->equals('border-width:10px;');
+    expect($this->renderer->render(['background_color' => '#dddddd']))->equals('background-color:#dddddd;');
+  }
+
+  public function testItShouldCompleteStyles() {
+    $styles = [
+      'border_radius' => 10,
+      'border_color' => '#fff',
+      'border_size' => 10,
+      'background_color' => '#dddddd',
+    ];
+    $result = $this->renderer->render($styles);
+    expect($result)->contains('border-radius:10px;');
+    expect($result)->contains('border-color:#fff;');
+    expect($result)->contains('border-width:10px;');
+    expect($result)->contains('background-color:#dddddd;');
+  }
+}