add phpunit tests

modules/tide_site_preview/src/Plugin/Block/PreviewLinksBlock.php

@@ -142,7 +142,12 @@ public function build() {
           if (!empty($sites['sections'][$site_id])) {
             $section = $this->siteHelper->getSiteById($sites['sections'][$site_id]);
           }
-          $preview_urls[$site_id] = $this->sitePreviewHelper->buildFrontendPreviewLink($this->currentNode, $site, $section, $this->getConfiguration());
+          $site_base_url = $this->siteHelper->getSiteBaseUrl($site);
+          $url = $this->currentNode->toUrl('canonical', [
+            'absolute' => TRUE,
+            'base_url' => $site_base_url,
+          ]);
+          $preview_urls[$site_id] = $this->sitePreviewHelper->buildFrontendPreviewLink($this->currentNode, $url, $site, $section, $this->getConfiguration());
         }
       }
     }

modules/tide_site_preview/src/TideSitePreviewHelper.php

@@ -49,7 +49,7 @@ public function __construct(TideSiteHelper $site_helper) {
    *   * name: The site/section name.
    *   * url: The absolute URL of the preview link.
    */
-  public function buildFrontendPreviewLink(NodeInterface $node, TermInterface $site, TermInterface $section = NULL, array $configuration = []) : array {
+  public function buildFrontendPreviewLink(NodeInterface $node, Url $url, TermInterface $site, TermInterface $section = NULL, array $configuration = []) : array {
     $url_options = [
       'attributes' => !(empty($configuration['open_new_window'])) ? ['target' => '_blank'] : [],
     ];
@@ -68,7 +68,7 @@ public function buildFrontendPreviewLink(NodeInterface $node, TermInterface $sit
     $site_base_url = $this->siteHelper->getSiteBaseUrl($site);
     if ($node->isPublished() && $node->isDefaultRevision()) {
       unset($url_options['query']['section']);
-      $preview_link['url'] = $this->getNodeFrontendUrl($node, $site_base_url, $url_options);
+      $preview_link['url'] = $this->getNodeFrontendUrl($url, $url_options);
     }
     else {
       $revision_id = $node->getLoadedRevisionId();
@@ -84,31 +84,19 @@ public function buildFrontendPreviewLink(NodeInterface $node, TermInterface $sit
   /**
    * Get the frontend URL of a node.
    *
-   * @param \Drupal\node\NodeInterface $node
+   * @param \Drupal\Core\Url $url
    *   The node.
-   * @param string $site_base_url
-   *   The base URL of the frontend.
-   * @param array $url_options
-   *   The extra options.
    *
    * @return \Drupal\Core\Url|string
    *   The Url.
    */
-  public function getNodeFrontendUrl(NodeInterface $node, $site_base_url = '', array $url_options = []) {
+  public function getNodeFrontendUrl(Url $url, array $url_options = []) {
     try {
-      $url = $node->toUrl('canonical', [
-        'absolute' => TRUE,
-        'base_url' => $site_base_url,
-      ] + $url_options);
-
-      $pattern = '/^\/site\-(\d+)\//';
-      if ($site_base_url) {
-        $pattern = '/' . preg_quote($site_base_url, '/') . '\/site\-(\d+)\//';
-      }
-      $clean_url = preg_replace($pattern, $site_base_url . '/', $url->toString());
+      $path = $url->toString();
+      $path = rtrim($path, '/');
+      $clean_url = preg_replace('/\/site\-(\d+)\//', '/', $path);
       return $clean_url ? Url::fromUri($clean_url, $url_options) : $url;
-    }
-    catch (Exception $exception) {
+    } catch (Exception $exception) {
       watchdog_exception('tide_site_preview', $exception);
     }
     return '';

modules/tide_site_preview/tests/src/Kernel/TideSitePreviewHelperTest.php

@@ -0,0 +1,78 @@
+<?php
+
+namespace Drupal\Tests\tide_site_preview\Kernel;
+
+use Drupal\Core\Url;
+use Drupal\Tests\token\Kernel\KernelTestBase;
+
+/**
+ * Tests the TideSitePreviewHelper
+ *
+ * @group tide_site_preview
+ */
+class TideSitePreviewHelperTest extends KernelTestBase {
+
+  /**
+   * The tide_site_preview.helper service.
+   *
+   * @var \Drupal\tide_site_preview\TideSitePreviewHelper
+   */
+  protected $tideSitePreviewHelper;
+
+  /**
+   * The modules to load to run the test.
+   *
+   * @var array
+   */
+  public static $modules = [
+    'tide_site',
+    'tide_site_preview',
+  ];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+    $this->installConfig(['tide_site_preview']);
+    $this->tideSitePreviewHelper =\Drupal::service('tide_site_preview.helper');
+  }
+
+  /**
+   * @covers ::getNodeFrontendUrl
+   * @dataProvider urlDataProvider
+   */
+  public function testgetNodeFrontendUrl($value, $expected) {
+    $url = Url::fromUri($value);
+    $url = $this->tideSitePreviewHelper->getNodeFrontendUrl($url);
+    $this->assertEquals($expected, $url->toString());
+  }
+
+  /**
+   * Data provider of test dates.
+   *
+   * @return array
+   *   Array of values.
+   */
+  public function urlDataProvider() {
+    return [
+      [
+        'value' => 'https://www.vic.gov.au/site-1/hello_world',
+        'expected' => 'https://www.vic.gov.au/hello_world',
+      ],
+      [
+        'value' => 'https://site-1/hello_world',
+        'expected' => 'https://hello_world',
+      ],
+      [
+        'value' => 'https://site-1/',
+        'expected' => 'https://site-1',
+      ],
+      [
+        'value' => 'https://site-1',
+        'expected' => 'https://site-1',
+      ],
+    ];
+  }
+
+}