Fix PHP 8.1 warning: passing null to string parameter

Author: mlocati

composer.json

@@ -53,7 +53,7 @@
     },
     "scripts": {
         "cs-fix": "php-cs-fixer fix --path-mode=intersection --config=./.php_cs.dist --ansi .",
-		"cs-check": "php-cs-fixer fix --path-mode=intersection --config=.php_cs.dist --ansi --dry-run --diff --diff-format=udiff .",
+        "cs-check": "php-cs-fixer fix --path-mode=intersection --config=.php_cs.dist --ansi --dry-run --diff --diff-format=udiff .",
         "test": "atoum --force-terminal && ./vendor/bin/behat --suite pickle --colors"
     },
     "extra": {
@@ -66,6 +66,9 @@
             },
             "hoa/stream:1.17.02.21": {
                 "PHP 8 fixes": "patches/hoa/stream/0001-Fix-PHP-8-compatibility.patch"
+            },
+            "justinrainbow/json-schema:5.2.10": {
+                "PHP 8.1 fixes": "patches/justinrainbow/json-schema/0001-PHP-8.1-fixes.patch"
             }
         }
     }

composer.lock

@@ -0,0 +1,20 @@
+From: Michele Locati <[email protected]>
+Date: Tue, 29 Jun 2021 18:08:46 +0200
+Subject: [PATCH] PHP 8.1 patched
+
+---
+ src/JsonSchema/Constraints/Constraint.php | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/src/JsonSchema/Constraints/Constraint.php b/src/JsonSchema/Constraints/Constraint.php
+--- a/src/JsonSchema/Constraints/Constraint.php
++++ b/src/JsonSchema/Constraints/Constraint.php
+@@ -45,7 +45,7 @@ abstract class Constraint extends BaseConstraint implements ConstraintInterface
+         $path = $path->withPropertyPaths(
+             array_merge(
+                 $path->getPropertyPaths(),
+-                array_filter(array($i), 'strlen')
++                array_filter(array((string) $i), 'strlen')
+             )
+         );
+