Drupal 7 - Search API views - "is empty" and "is not empty" operators.

search_api_views-empty-filter.patch

diff --git a/contrib/search_api_views/includes/handler_filter.inc b/contrib/search_api_views/includes/handler_filter.inc
index cc965da..3ac19f0 100644
--- a/contrib/search_api_views/includes/handler_filter.inc
+++ b/contrib/search_api_views/includes/handler_filter.inc
@@ -37,6 +37,8 @@ class SearchApiViewsHandlerFilter extends views_handler_filter {
       '<>' => t('Is not equal to'),
       '>=' => t('Is greater than or equal to'),
       '>' => t('Is greater than'),
+      'NULL' => t('Is empty'),
+      'NOT NULL' => t('Is not empty'),
     );
   }

@@ -59,11 +61,19 @@ class SearchApiViewsHandlerFilter extends views_handler_filter {
    * Add this filter to the query.
    */
   public function query() {
-    while (is_array($this->value)) {
-      $this->value = $this->value ? reset($this->value) : NULL;
+    if ($this->operator === 'NULL') {
+      $this->query->condition($this->real_field, NULL, '=', $this->options['group']);
+    }
+    elseif ($this->operator === 'NOT NULL') {
+      $this->query->condition($this->real_field, NULL, '<>', $this->options['group']);
     }
-    if ($this->value) {
-      $this->query->condition($this->real_field, $this->value, $this->operator, $this->options['group']);
+    else {
+      while (is_array($this->value)) {
+        $this->value = $this->value ? reset($this->value) : NULL;
+      }
+      if ($this->value) {
+        $this->query->condition($this->real_field, $this->value, $this->operator, $this->options['group']);
+      }
     }
   }