From be1e34dedea2beeb0fcea0193af41d4eb7732caf Mon Sep 17 00:00:00 2001
From: Oleg Zhulnev <plbsid@gmail.com>
Date: Mon, 22 Feb 2021 18:05:39 +0300
Subject: [PATCH] Do not decrement min integer value

---
 src/Mutator/Number/DecrementInteger.php               |  5 +++++
 tests/phpunit/Mutator/Number/DecrementIntegerTest.php | 10 ++++++++++
 2 files changed, 15 insertions(+)

diff --git a/src/Mutator/Number/DecrementInteger.php b/src/Mutator/Number/DecrementInteger.php
index 16c521375..8a2ebdb95 100644
--- a/src/Mutator/Number/DecrementInteger.php
+++ b/src/Mutator/Number/DecrementInteger.php
@@ -40,6 +40,7 @@
 use Infection\Mutator\GetMutatorName;
 use Infection\Mutator\MutatorCategory;
 use Infection\PhpParser\Visitor\ParentConnector;
+use const PHP_INT_MIN;
 use PhpParser\Node;
 
 /**
@@ -97,6 +98,10 @@ public function canMutate(Node $node): bool
             return false;
         }
 
+        if ($node->value === PHP_INT_MIN) {
+            return false;
+        }
+
         if (
             $node->value === 1
             && ($this->isPartOfComparison($node) || ParentConnector::getParent($node) instanceof Node\Expr\Assign)
diff --git a/tests/phpunit/Mutator/Number/DecrementIntegerTest.php b/tests/phpunit/Mutator/Number/DecrementIntegerTest.php
index b4b00a079..2f3e1d9f0 100644
--- a/tests/phpunit/Mutator/Number/DecrementIntegerTest.php
+++ b/tests/phpunit/Mutator/Number/DecrementIntegerTest.php
@@ -504,6 +504,16 @@ public function mutationsProvider(): iterable
 <?php
 
 preg_split('//', 'string', -2);
+PHP
+        ];
+
+        yield 'It does not decrement min int' => [
+            <<<'PHP'
+<?php
+
+if ($a === -9223372036854775808) {
+    echo 'bar';
+}
 PHP
         ];
     }