Fix typehint errors

Author: ADmad

composer.json

@@ -76,7 +76,7 @@
         "test": "phpunit",
         "stan": "phpstan analyse src/ && psalm --show-info=false",
         "psalm": "psalm --show-info=false",
-        "stan-setup": "cp composer.json composer.backup && composer require --dev phpstan/phpstan:^0.11 vimeo/psalm:^3.0 && mv composer.backup composer.json",
+        "stan-setup": "cp composer.json composer.backup && composer require --dev phpstan/phpstan:^0.12 vimeo/psalm:^3.7 && mv composer.backup composer.json",
         "test-coverage": "phpunit --coverage-clover=clover.xml"
     }
 }

phpstan.neon

@@ -1,6 +1,5 @@
 parameters:
     level: 6
+    checkMissingIterableValueType: false
     autoload_files:
         - tests/bootstrap.php
-    ignoreErrors:
-        - '#Parameter \#1 $fp of function fwrite expects resource, resource|false given#'

src/View/CsvView.php

@@ -194,7 +194,7 @@ public function __construct(
      *
      * @param array|string $serialize The name(s) of the view variable(s) that
      *   need(s) to be serialized
-     * @return string|false The serialized data or false.
+     * @return string The serialized data or false.
      */
     protected function _serialize($serialize): string
     {
@@ -272,17 +272,17 @@ protected function _renderContent(): void
      *
      * @param array|null $row Row data
      *
-     * @return null|string CSV with all data to date
+     * @return string CSV with all data to date
      */
-    protected function _renderRow(?array $row = null): ?string
+    protected function _renderRow(?array $row = null): string
     {
         static $csv = '';
 
         if ($this->_resetStaticVariables) {
             $csv = '';
             $this->_resetStaticVariables = false;
 
-            return null;
+            return '';
         }
 
         $csv .= (string)$this->_generateRow($row);