diff --git a/src/Plugin/facets/url_processor/QueryString.php b/src/Plugin/facets/url_processor/QueryString.php
index 346b294..78812b5 100644
--- a/src/Plugin/facets/url_processor/QueryString.php
+++ b/src/Plugin/facets/url_processor/QueryString.php
@@ -69,7 +69,7 @@ class QueryString extends UrlProcessorPluginBase {
 
     /** @var \Drupal\facets\Result\ResultInterface $result */
     foreach ($results as &$result) {
-      $filter_string = $this->url_alias . ':' . $result->getRawValue();
+      $filter_string = $this->url_alias . self::SEPARATOR . $result->getRawValue();
       $result_get_params = clone $get_params;
 
       $filter_params = $result_get_params->get($this->filterKey, [], TRUE);
diff --git a/src/Tests/UrlIntegrationTest.php b/src/Tests/UrlIntegrationTest.php
new file mode 100644
index 0000000..62339d3
--- /dev/null
+++ b/src/Tests/UrlIntegrationTest.php
@@ -0,0 +1,104 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\facets\Tests\UrlIntegrationTest.
+ */
+
+namespace Drupal\facets\Tests;
+
+use \Drupal\facets\Tests\WebTestBase as FacetWebTestBase;
+
+/**
+ * Tests the overall functionality of the Facets admin UI.
+ *
+ * @group facets
+ */
+class UrlIntegrationTest extends FacetWebTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static $modules = [
+    'views',
+    'node',
+    'search_api',
+    'search_api_test_backend',
+    'facets',
+    'search_api_test_views',
+    'block',
+    'facets_search_api_dependency',
+    'facets_query_processor',
+  ];
+
+  /**
+   * Tests various url integration things.
+   */
+  public function testUrlIntegration() {
+    $this->drupalLogin($this->adminUser);
+
+    $this->insertExampleContent();
+    $this->assertEqual($this->indexItems($this->indexId), 5, '5 items were indexed.');
+
+    $id = 'facet';
+    $name = '&^Facet@#1';
+
+    $facet_add_page = 'admin/config/search/facets/add-facet';
+    $this->drupalGet($facet_add_page);
+    $this->assertResponse(200);
+
+    $form_values = [
+      'id' => $id,
+      'status' => 1,
+      'url_alias' => $id,
+      'name' => $name,
+      'facet_source_id' => 'search_api_views:search_api_test_views_fulltext:page_1',
+      'facet_source_configs[search_api_views:search_api_test_views_fulltext:page_1][field_identifier]' => 'entity:entity_test/type',
+    ];
+    $this->drupalPostForm(NULL, ['facet_source_id' => 'search_api_views:search_api_test_views_fulltext:page_1'], $this->t('Configure facet source'));
+    $this->drupalPostForm(NULL, $form_values, $this->t('Save'));
+    $this->assertNoText('field is required.');
+
+    $this->assertRaw(t('Facet %name has been created.', ['%name' => $name]));
+
+    $this->drupalGet('admin/config/search/facets');
+
+    $edit = [
+      'filterKey' => 'y',
+      'urlProcessor' => 'dummy_query',
+    ];
+    $this->clickLink($this->t('Configure'));
+    $this->drupalPostForm(NULL, $edit, $this->t('Save'));
+
+    /** @var \Drupal\facets\FacetInterface $facet */
+    $facet = \Drupal::service('entity_type.manager')->getStorage('facets_facet')->load($id);
+    $block_values = [
+      [
+        'label' => 'Facet Block',
+        'tr' => '16',
+        'plugin_id' => 'facet_block',
+        'settings' => [
+          'region' => 'footer',
+          'id' => str_replace('_', '-', $id),
+          'context_mapping' => [
+            'facet' => '@facets.facet_context:' . $facet->uuid(),
+          ],
+        ],
+        'test_weight' => '0',
+      ],
+    ];
+    foreach ($block_values as $values) {
+      $this->drupalPlaceBlock($values['plugin_id'], $values['settings']);
+    }
+
+    $this->drupalGet('search-api-test-fulltext');
+    $this->assertLink('item');
+    $this->assertLink('article');
+
+    $this->clickLink('item');
+
+    $this->assertLink('(-) item');
+    $this->assertUrl('search-api-test-fulltext?y[0]=facet||item');
+  }
+
+}
diff --git a/tests/facets_query_processor/facets_query_processor.info.yml b/tests/facets_query_processor/facets_query_processor.info.yml
new file mode 100644
index 0000000..8347423
--- /dev/null
+++ b/tests/facets_query_processor/facets_query_processor.info.yml
@@ -0,0 +1,6 @@
+name: 'Facets query processor'
+type: module
+description: 'Facets query processor'
+package: 'Search'
+core: 8.x
+hidden: true
diff --git a/tests/facets_query_processor/src/Plugin/facets/url_processor/DummyQuery.php b/tests/facets_query_processor/src/Plugin/facets/url_processor/DummyQuery.php
new file mode 100644
index 0000000..764e67c
--- /dev/null
+++ b/tests/facets_query_processor/src/Plugin/facets/url_processor/DummyQuery.php
@@ -0,0 +1,143 @@
+<?php
+
+/**
+ * @file
+ * Contains Drupal\facets_query_processor\Plugin\facets\url_processor\DummyQuery.
+ */
+
+namespace Drupal\facets_query_processor\Plugin\facets\url_processor;
+
+use Drupal\Core\Url;
+use Drupal\facets\FacetInterface;
+use Drupal\facets\UrlProcessor\UrlProcessorPluginBase;
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * Query string URL processor.
+ *
+ * @FacetsUrlProcessor(
+ *   id = "dummy_query",
+ *   label = @Translation("Dummy query"),
+ *   description = @Translation("Dummy for testing.")
+ * )
+ */
+class DummyQuery extends UrlProcessorPluginBase {
+
+  /**
+   * A string that separates the filters in the query string.
+   */
+  const SEPARATOR = '||';
+
+  /**
+   * A string of how to represent the facet in the url.
+   *
+   * @var string
+   */
+  protected $url_alias;
+
+  /**
+   * An array of active filters.
+   *
+   * @var string[]
+   *   An array containing the active filters
+   */
+  protected $activeFilters = [];
+
+  /**
+   * {@inheritdoc}
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, Request $request) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition, $request);
+    $this->initializeActiveFilters();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildUrls(FacetInterface $facet, array $results) {
+    // Create links for all the values.
+    // First get the current list of get parameters.
+    $get_params = $this->request->query;
+
+    // Set the url alias from the the facet object.
+    $this->url_alias = $facet->getUrlAlias();
+
+    // No results are found for this facet, so don't try to create urls.
+    if (empty($results)) {
+      return [];
+    }
+
+    /** @var \Drupal\facets\Result\ResultInterface $result */
+    foreach ($results as &$result) {
+      $filter_string = $this->url_alias . self::SEPARATOR . $result->getRawValue();
+      $result_get_params = clone $get_params;
+
+      $filter_params = $result_get_params->get($this->filterKey, [], TRUE);
+      // If the value is active, remove the filter string from the parameters.
+      if ($result->isActive()) {
+        foreach ($filter_params as $key => $filter_param) {
+          if ($filter_param == $filter_string) {
+            unset($filter_params[$key]);
+          }
+        }
+      }
+      // If the value is not active, add the filter string.
+      else {
+        $filter_params[] = $filter_string;
+      }
+
+      $result_get_params->set($this->filterKey, $filter_params);
+      $request = $this->request;
+      if ($facet->getFacetSource()->getPath()) {
+        $request = Request::create('/' . $facet->getFacetSource()->getPath());
+      }
+      $url = Url::createFromRequest($request);
+      $url->setOption('query', $result_get_params->all());
+
+      $result->setUrl($url);
+    }
+
+    return $results;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setActiveItems(FacetInterface $facet) {
+    // Set the url alias from the the facet object.
+    $this->url_alias = $facet->getUrlAlias();
+
+    // Get the filter key of the facet.
+    if (isset($this->activeFilters[$this->url_alias])) {
+      foreach ($this->activeFilters[$this->url_alias] as $value) {
+        $facet->setActiveItem(trim($value, '"'));
+      }
+    }
+  }
+
+  /**
+   * Initialize the active filters.
+   *
+   * Get all the filters that are active. This method only get's all the
+   * filters but doesn't assign them to facets. In the processFacet method the
+   * active values for a specific facet are added to the facet.
+   */
+  protected function initializeActiveFilters() {
+    $url_parameters = $this->request->query;
+
+    // Get the active facet parameters.
+    $active_params = $url_parameters->get($this->filterKey, array(), TRUE);
+
+    // Explode the active params on the separator.
+    foreach ($active_params as $param) {
+      list($key, $value) = explode(self::SEPARATOR, $param);
+      if (!isset($this->activeFilters[$key])) {
+        $this->activeFilters[$key] = [$value];
+      }
+      else {
+        $this->activeFilters[$key][] = $value;
+      }
+    }
+  }
+
+}