From 077ebb6e5c65489e80be82b0742375c043124db5 Mon Sep 17 00:00:00 2001
From: Richard Popelis <popelis@efabrica.sk>
Date: Tue, 25 Jul 2023 14:29:01 +0200
Subject: [PATCH 1/2] EnforceArrowFunctionRule

---
 src/Rule/General/EnforceArrowFunctionRule.php | 37 +++++++++++++++++++
 1 file changed, 37 insertions(+)
 create mode 100644 src/Rule/General/EnforceArrowFunctionRule.php

diff --git a/src/Rule/General/EnforceArrowFunctionRule.php b/src/Rule/General/EnforceArrowFunctionRule.php
new file mode 100644
index 0000000..b5ca073
--- /dev/null
+++ b/src/Rule/General/EnforceArrowFunctionRule.php
@@ -0,0 +1,37 @@
+<?php
+
+namespace Efabrica\PHPStanRules\Rule\General;
+
+use PhpParser\Node;
+use PhpParser\Node\Expr\Closure;
+use PHPStan\Analyser\Scope;
+use PHPStan\Rules\Rule;
+
+class EnforceArrowFunctionRule
+{
+    public function getNodeType(): string
+    {
+        return Closure::class;
+    }
+
+    /**
+     * @param Closure $node
+     * @param Scope   $scope
+     * @return array|string[]
+     */
+    public function processNode(Node $node, Scope $scope): array
+    {
+        if ($node->stmts === null || count($node->stmts) !== 1) {
+            return [];
+        }
+
+        $onlyStatement = $node->stmts[0];
+        if (!$onlyStatement instanceof Node\Stmt\Return_) {
+            return [];
+        }
+
+        return [
+            'Closure only has a single return statement. Use an arrow function instead.',
+        ];
+    }
+}

From 0bc96b4c02826892861e36b07ece034f2b73f03b Mon Sep 17 00:00:00 2001
From: Richard Popelis <popelis@efabrica.sk>
Date: Tue, 25 Jul 2023 14:30:25 +0200
Subject: [PATCH 2/2] fix

---
 src/Rule/General/EnforceArrowFunctionRule.php | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Rule/General/EnforceArrowFunctionRule.php b/src/Rule/General/EnforceArrowFunctionRule.php
index b5ca073..47eb951 100644
--- a/src/Rule/General/EnforceArrowFunctionRule.php
+++ b/src/Rule/General/EnforceArrowFunctionRule.php
@@ -7,7 +7,7 @@
 use PHPStan\Analyser\Scope;
 use PHPStan\Rules\Rule;
 
-class EnforceArrowFunctionRule
+class EnforceArrowFunctionRule implements Rule
 {
     public function getNodeType(): string
     {
@@ -25,7 +25,7 @@ public function processNode(Node $node, Scope $scope): array
             return [];
         }
 
-        $onlyStatement = $node->stmts[0];
+        $onlyStatement = reset($node->stmts);
         if (!$onlyStatement instanceof Node\Stmt\Return_) {
             return [];
         }