diff --git a/.travis.yml b/.travis.yml
index facd522..fcdf5c4 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -42,3 +42,10 @@ jobs:
       - *composerupdate
     script:
       - *phpunit
+  - stage: test
+    php: 7.4
+    env: PREFER_LOWEST=""
+    before_script:
+      - *composerupdate
+    script:
+      - *phpunit
diff --git a/src/SQLParser/Node/NodeFactory.php b/src/SQLParser/Node/NodeFactory.php
index b06a8fd..f69b327 100644
--- a/src/SQLParser/Node/NodeFactory.php
+++ b/src/SQLParser/Node/NodeFactory.php
@@ -183,7 +183,7 @@ public static function toObject(array $desc)
                 }
                 $expr->setJoinType($joinType);
 
-                if (isset($desc['alias'])) {
+                if (isset($desc['alias']['name'])) {
                     $expr->setAlias($desc['alias']['name']);
                 }
                 $subTreeNodes = self::buildFromSubtree($desc['ref_clause']);
@@ -366,7 +366,7 @@ public static function toObject(array $desc)
                     $expr->setSubTree(self::buildFromSubtree($desc['sub_tree']));
                 }
 
-                if (isset($desc['alias'])) {
+                if (isset($desc['alias']['name'])) {
                     $expr->setAlias($desc['alias']['name']);
                 }
                 if (isset($desc['direction'])) {