diff --git a/rules-tests/DeadCode/Rector/Property/RemoveUnusedPrivatePropertyRector/Fixture/fluent_call_with_concat.php.inc b/rules-tests/DeadCode/Rector/Property/RemoveUnusedPrivatePropertyRector/Fixture/fluent_call_with_concat.php.inc
new file mode 100644
index 00000000000..2264eca5bf8
--- /dev/null
+++ b/rules-tests/DeadCode/Rector/Property/RemoveUnusedPrivatePropertyRector/Fixture/fluent_call_with_concat.php.inc
@@ -0,0 +1,36 @@
+<?php
+
+namespace Rector\Tests\DeadCode\Rector\Property\RemoveUnusedPrivatePropertyRector\Fixture;
+
+class FluentCallWithConcat
+{
+	private static $directory = 'CacheFactory';
+	private $cacheFactory;
+	private $config;
+
+    public function run()
+	{
+		$this->config             = new Cache();
+		$this->config->storePath .= self::$directory;
+	}
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\DeadCode\Rector\Property\RemoveUnusedPrivatePropertyRector\Fixture;
+
+class FluentCallWithConcat
+{
+	private static $directory = 'CacheFactory';
+	private $config;
+
+    public function run()
+	{
+		$this->config             = new Cache();
+		$this->config->storePath .= self::$directory;
+	}
+}
+
+?>
diff --git a/rules/Removing/NodeManipulator/ComplexNodeRemover.php b/rules/Removing/NodeManipulator/ComplexNodeRemover.php
index 280a806a786..b827f254df3 100644
--- a/rules/Removing/NodeManipulator/ComplexNodeRemover.php
+++ b/rules/Removing/NodeManipulator/ComplexNodeRemover.php
@@ -51,10 +51,13 @@ public function removePropertyAndUsages(Property $property, array $classMethodNa
                 continue;
             }
 
-            // remove assigns
             $assign = $this->resolveAssign($propertyFetch);
-            $this->assignRemover->removeAssignNode($assign);
+            if (! $assign instanceof Assign) {
+                return;
+            }
 
+            // remove assigns
+            $this->assignRemover->removeAssignNode($assign);
             $this->removeConstructorDependency($assign);
         }
 
@@ -95,7 +98,7 @@ private function shouldSkipPropertyForClassMethod(Expr $expr, array $classMethod
     /**
      * @param PropertyFetch|StaticPropertyFetch $expr
      */
-    private function resolveAssign(Expr $expr): Assign
+    private function resolveAssign(Expr $expr): ?Assign
     {
         $assign = $expr->getAttribute(AttributeKey::PARENT_NODE);
 
@@ -104,7 +107,7 @@ private function resolveAssign(Expr $expr): Assign
         }
 
         if (! $assign instanceof Assign) {
-            throw new ShouldNotHappenException("Can't handle this situation");
+            return null;
         }
 
         return $assign;