Add soft level errors distinction for SendGrid service

[MAILPOET-1154]

lib/Mailer/Methods/ErrorMappers/SendGridMapper.php

@@ -13,10 +13,15 @@ class SendGridMapper {
       $response['errors'][0] :
       sprintf(__('%s has returned an unknown error.', 'mailpoet'), Mailer::METHOD_SENDGRID);
 
+    $level = MailerError::LEVEL_HARD;
+    if(strpos($response, 'Invalid email address') === 0) {
+      $level = MailerError::LEVEL_SOFT;
+    }
+
     $subscriber_errors = [];
     if(empty($extra_params['test_email'])) {
       $subscriber_errors[] = new SubscriberError($subscriber, null);
     }
-    return new MailerError(MailerError::OPERATION_SEND, MailerError::LEVEL_HARD, $response, null, $subscriber_errors);
+    return new MailerError(MailerError::OPERATION_SEND, $level, $response, null, $subscriber_errors);
   }
 }

tests/unit/Mailer/Methods/ErrorMappers/SendGridMapperTest.php

@@ -0,0 +1,36 @@
+<?php
+namespace MailPoet\Test\Mailer\Methods\ErrorMappers;
+
+use MailPoet\Mailer\MailerError;
+use MailPoet\Mailer\Methods\ErrorMappers\SendGridMapper;
+
+class SendGridMapperTest extends \MailPoetTest {
+
+  /** @var SendGridMapper*/
+  private $mapper;
+
+  /** @var array */
+  private $response = [];
+
+  function _before() {
+    $this->mapper = new SendGridMapper();
+    $this->response = [
+      'errors' => [
+        'Some message',
+      ]
+    ];
+  }
+
+  function testGetProperError() {
+    $error = $this->mapper->getErrorFromResponse($this->response, 'john@rambo.com', []);
+    expect($error->getLevel())->equals(MailerError::LEVEL_HARD);
+    expect($error->getMessage())->equals('Some message');
+    expect($error->getSubscriberErrors()[0]->getEmail())->equals('john@rambo.com');
+  }
+
+  function testGetSoftErrorForInvalidEmail() {
+    $this->response['errors'][0] = 'Invalid email address ,,@';
+    $error = $this->mapper->getErrorFromResponse($this->response, ',,@', []);
+    expect($error->getLevel())->equals(MailerError::LEVEL_SOFT);
+  }
+}