fix: fixes for unique items, pattern properties and additional properties

Author: DannyvdSluijs

src/JsonSchema/Constraints/Drafts/Draft06/AdditionalPropertiesConstraint.php

@@ -47,7 +47,7 @@ public function check(&$value, $schema = null, ?JsonPointer $path = null, $i = n
 
             foreach ($additionalProperties as $key => $_) {
                 foreach ($patterns as $pattern) {
-                    if (preg_match("/{$pattern}/", $key)) {
+                    if (preg_match("/{$pattern}/", (string) $key)) {
                         unset($additionalProperties[$key]);
                         break;
                     }

src/JsonSchema/Constraints/Drafts/Draft06/PatternPropertiesConstraint.php

@@ -35,7 +35,7 @@ public function check(&$value, $schema = null, ?JsonPointer $path = null, $i = n
 
         foreach ($properties as $propertyName => $propertyValue) {
             foreach ($schema->patternProperties as $patternPropertyRegex => $patternPropertySchema) {
-                if (preg_match('/' . str_replace('/', '\/', $patternPropertyRegex) . '/', $propertyName)) {
+                if (preg_match('/' . str_replace('/', '\/', $patternPropertyRegex) . '/', (string) $propertyName)) {
                     $schemaConstraint = $this->factory->createInstanceFor('schema');
                     $schemaConstraint->check($propertyValue, $patternPropertySchema, $path, $i);
                     if ($schemaConstraint->isValid()) {

src/JsonSchema/Constraints/Drafts/Draft06/UniqueItemsConstraint.php

@@ -25,6 +25,9 @@ public function check(&$value, $schema = null, ?JsonPointer $path = null, $i = n
         if (!property_exists($schema, 'uniqueItems')) {
             return;
         }
+        if (!is_array($value)) {
+            return;
+        }
 
         if ($schema->uniqueItems !== true) {
             // If unique items not is true duplicates are allowed.