From 65837daa983762ba931558929e9ba0b9949c597f Mon Sep 17 00:00:00 2001
From: MarkBaker <mark@lange.demon.co.uk>
Date: Fri, 29 Jan 2021 15:43:49 +0100
Subject: [PATCH] Named formula fix for empty formula value

---
 composer.json                       | 2 +-
 src/PhpSpreadsheet/NamedFormula.php | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/composer.json b/composer.json
index c6f8e30e..0fffd510 100644
--- a/composer.json
+++ b/composer.json
@@ -63,7 +63,7 @@
     },
     "require-dev": {
         "dompdf/dompdf": "^0.8.5",
-        "friendsofphp/php-cs-fixer": "^2.16",
+        "friendsofphp/php-cs-fixer": "^2.16||^2.18",
         "jpgraph/jpgraph": "^4.0",
         "mpdf/mpdf": "^8.0",
         "phpcompatibility/php-compatibility": "^9.3",
diff --git a/src/PhpSpreadsheet/NamedFormula.php b/src/PhpSpreadsheet/NamedFormula.php
index eeddbbcb..500151f0 100644
--- a/src/PhpSpreadsheet/NamedFormula.php
+++ b/src/PhpSpreadsheet/NamedFormula.php
@@ -17,7 +17,7 @@ class NamedFormula extends DefinedName
         ?Worksheet $scope = null
     ) {
         // Validate data
-        if (empty($formula)) {
+        if (!isset($formula)) {
             throw new Exception('You must specify a Formula value for a Named Formula');
         }
         parent::__construct($name, $worksheet, $formula, $localOnly, $scope);