diff --git a/src/Support/Str.php b/src/Support/Str.php
index 9ed75c1f..21ee5c5b 100644
--- a/src/Support/Str.php
+++ b/src/Support/Str.php
@@ -61,7 +61,8 @@ final class Str
     {
         $code = self::PREFIX.str_replace(' ', '_', $code);
 
-        return (string) preg_replace('/[^A-Z_a-z0-9]/', '_', $code);
+        // sticks to PHP8.2 function naming rules https://www.php.net/manual/en/functions.user-defined.php
+        return (string) preg_replace('/[^a-zA-Z0-9_\x80-\xff]/', '_', $code);
     }
 
     /**
diff --git a/tests/Unit/TestName.php b/tests/Unit/TestName.php
index 3f52e700..b7f91d54 100644
--- a/tests/Unit/TestName.php
+++ b/tests/Unit/TestName.php
@@ -11,3 +11,60 @@ it('may start with P', function (string $real, string $toBePrinted) {
     ['PPPackages\Foo', 'PPPackages\Foo'],
     ['PPPackages\Foo', 'PPPackages\Foo'],
 ]);
+
+$names = [
+    'ふ+が+' => '__pest_evaluable_ふ_が_',
+    'ほげ' => '__pest_evaluable_ほげ',
+    '卜竹弓一十山' => '__pest_evaluable_卜竹弓一十山',
+    'アゴデヸ' => '__pest_evaluable_アゴデヸ',
+    '!p8VrB' => '__pest_evaluable__p8VrB',
+    '&xe6VeKWF#n4' => '__pest_evaluable__xe6VeKWF_n4',
+    '%%HurHUnw7zM!' => '__pest_evaluable___HurHUnw7zM_',
+    'rundeliekend' => '__pest_evaluable_rundeliekend',
+    'g%%c!Jt9$fy#Kf' => '__pest_evaluable_g__c_Jt9_fy_Kf',
+    'NRs*Gz2@hmB$W$BPD%%b2U%3P%z%apnwSX' => '__pest_evaluable_NRs_Gz2_hmB_W_BPD__b2U_3P_z_apnwSX',
+    'ÀĤ{¼÷' => '__pest_evaluable_ÀĤ_¼÷',
+    'ìèéàòç' => '__pest_evaluable_ìèéàòç',
+    'زهراء المعادي' => '__pest_evaluable_زهراء_المعادي',
+    'الجبيهه' => '__pest_evaluable_الجبيهه',
+    'الظهران' => '__pest_evaluable_الظهران',
+    'Каролин' => '__pest_evaluable_Каролин',
+    'অ্যান্টার্কটিকা' => '__pest_evaluable_অ্যান্টার্কটিকা',
+    'Frýdek-Místek"' => '__pest_evaluable_Frýdek_Místek_',
+    'Allingåbro&' => '__pest_evaluable_Allingåbro_',
+    'Κεντροαφρικανική Δημοκρατία' => '__pest_evaluable_Κεντροαφρικανική_Δημοκρατία',
+    'آذربایجان غربی' => '__pest_evaluable_آذربایجان_غربی',
+    'זימבבואה' => '__pest_evaluable_זימבבואה',
+    'Belišće' => '__pest_evaluable_Belišće',
+    'Գվատեմալա' => '__pest_evaluable_Գվատեմալա',
+    'パプアニューギニア' => '__pest_evaluable_パプアニューギニア',
+    '富山県' => '__pest_evaluable_富山県',
+    'Қарағанды' => '__pest_evaluable_Қарағанды',
+    'Қостанай' => '__pest_evaluable_Қостанай',
+    '안양시 동안구' => '__pest_evaluable_안양시_동안구',
+    'Itālija' => '__pest_evaluable_Itālija',
+    'Honningsvåg' => '__pest_evaluable_Honningsvåg',
+    'Águeda' => '__pest_evaluable_Águeda',
+    'Râșcani' => '__pest_evaluable_Râșcani',
+    'Năsăud' => '__pest_evaluable_Năsăud',
+    'Орехово-Зуево' => '__pest_evaluable_Орехово_Зуево',
+    'Čereňany' => '__pest_evaluable_Čereňany',
+    'Moravče' => '__pest_evaluable_Moravče',
+    'Šentjernej' => '__pest_evaluable_Šentjernej',
+    'Врање' => '__pest_evaluable_Врање',
+    'Крушевац' => '__pest_evaluable_Крушевац',
+    'Åkersberga' => '__pest_evaluable_Åkersberga',
+    'บอสเนียและเฮอร์เซโกวีนา' => '__pest_evaluable_บอสเนียและเฮอร์เซโกวีนา',
+    'Birleşik Arap Emirlikleri' => '__pest_evaluable_Birleşik_Arap_Emirlikleri',
+    'Німеччина' => '__pest_evaluable_Німеччина',
+    'Nam Định' => '__pest_evaluable_Nam_Định',
+    '呼和浩特' => '__pest_evaluable_呼和浩特',
+];
+
+foreach ($names as $name => $methodName) {
+    test($name)
+        ->expect(fn () => static::getLatestPrintableTestCaseMethodName())
+        ->toBe($name)
+        ->and(fn () => $this->name())
+        ->toBe($methodName);
+}