diff --git a/tests/system/Commands/ClearDebugbarTest.php b/tests/system/Commands/ClearDebugbarTest.php
index b8f6fa13e535..f3062d9d5ac7 100644
--- a/tests/system/Commands/ClearDebugbarTest.php
+++ b/tests/system/Commands/ClearDebugbarTest.php
@@ -39,7 +39,7 @@ protected function createDummyDebugbarJson(): void
 
         // create 10 dummy debugbar json files
         for ($i = 0; $i < 10; $i++) {
-            $path = str_replace($time, $time - $i, $path);
+            $path = str_replace((string) $time, (string) ($time - $i), $path);
             file_put_contents($path, "{}\n");
 
             $time -= $i;
diff --git a/tests/system/CommonFunctionsSendTest.php b/tests/system/CommonFunctionsSendTest.php
index a580366277fb..4e88dd96644c 100644
--- a/tests/system/CommonFunctionsSendTest.php
+++ b/tests/system/CommonFunctionsSendTest.php
@@ -43,7 +43,7 @@ public function testRedirectResponseCookiesSent(): void
 
         $response = redirect()->route('login')
             ->setCookie('foo', 'onething', YEAR)
-            ->setCookie('login_time', $loginTime, YEAR);
+            ->setCookie('login_time', (string) $loginTime, YEAR);
         $response->pretend(false);
         $this->assertTrue($response->hasCookie('foo', 'onething'));
         $this->assertTrue($response->hasCookie('login_time'));
diff --git a/tests/system/CommonFunctionsTest.php b/tests/system/CommonFunctionsTest.php
index b6702c5a7376..15c52896a17b 100644
--- a/tests/system/CommonFunctionsTest.php
+++ b/tests/system/CommonFunctionsTest.php
@@ -576,7 +576,7 @@ public function testRedirectResponseCookies1(): void
 
         $answer1 = redirect()->route('login')
             ->setCookie('foo', 'onething', YEAR)
-            ->setCookie('login_time', $loginTime, YEAR);
+            ->setCookie('login_time', (string) $loginTime, YEAR);
 
         $this->assertTrue($answer1->hasCookie('foo', 'onething'));
         $this->assertTrue($answer1->hasCookie('login_time'));
diff --git a/tests/system/Debug/Toolbar/Collectors/HistoryTest.php b/tests/system/Debug/Toolbar/Collectors/HistoryTest.php
index 1286a489b14f..8e056fbc755c 100644
--- a/tests/system/Debug/Toolbar/Collectors/HistoryTest.php
+++ b/tests/system/Debug/Toolbar/Collectors/HistoryTest.php
@@ -61,7 +61,7 @@ private function createDummyDebugbarJson(): void
 
         // create 20 dummy debugbar json files
         for ($i = 0; $i < 20; $i++) {
-            $path = str_replace($time, sprintf('%.6f', $time - self::STEP), $path);
+            $path = str_replace((string) $time, sprintf('%.6f', $time - self::STEP), $path);
             file_put_contents($path, json_encode($dummyData));
             $time = sprintf('%.6f', $time - self::STEP);
         }
diff --git a/tests/system/HTTP/ResponseSendTest.php b/tests/system/HTTP/ResponseSendTest.php
index 437d379fdf9d..f1ceac8cd793 100644
--- a/tests/system/HTTP/ResponseSendTest.php
+++ b/tests/system/HTTP/ResponseSendTest.php
@@ -127,9 +127,11 @@ public function testRedirectResponseCookies(): void
 
         $answer1 = $response->redirect('/login')
             ->setCookie('foo', 'bar', YEAR)
-            ->setCookie('login_time', $loginTime, YEAR);
+            ->setCookie('login_time', (string) $loginTime, YEAR);
+
         $this->assertTrue($answer1->hasCookie('foo', 'bar'));
         $this->assertTrue($answer1->hasCookie('login_time'));
+
         $response->setBody('Hello');
 
         // send it
diff --git a/tests/system/HTTP/ResponseTest.php b/tests/system/HTTP/ResponseTest.php
index e08dc1de62a3..212ad674b460 100644
--- a/tests/system/HTTP/ResponseTest.php
+++ b/tests/system/HTTP/ResponseTest.php
@@ -551,7 +551,7 @@ public function testRedirectResponseCookies(): void
         $response = new Response(new App());
         $answer1  = $response->redirect('/login')
             ->setCookie('foo', 'bar', YEAR)
-            ->setCookie('login_time', $loginTime, YEAR);
+            ->setCookie('login_time', (string) $loginTime, YEAR);
 
         $this->assertTrue($answer1->hasCookie('foo'));
         $this->assertTrue($answer1->hasCookie('login_time'));
diff --git a/tests/system/Helpers/CookieHelperTest.php b/tests/system/Helpers/CookieHelperTest.php
index 45796658fecc..51a00b6ba0a8 100755
--- a/tests/system/Helpers/CookieHelperTest.php
+++ b/tests/system/Helpers/CookieHelperTest.php
@@ -250,10 +250,12 @@ public function testSameSiteParamArray(): void
 
     public function testSameSiteParam(): void
     {
-        set_cookie($this->name, $this->value, $this->expire, '', '', '', '', '', 'Strict');
+        set_cookie($this->name, $this->value, $this->expire, '', '', '', null, null, 'Strict');
 
         $this->assertTrue($this->response->hasCookie($this->name));
+
         $theCookie = $this->response->getCookie($this->name);
+
         $this->assertSame('Strict', $theCookie->getSameSite());
 
         delete_cookie($this->name);
diff --git a/tests/system/Helpers/FilesystemHelperTest.php b/tests/system/Helpers/FilesystemHelperTest.php
index e92505cc8a91..af682c459f23 100644
--- a/tests/system/Helpers/FilesystemHelperTest.php
+++ b/tests/system/Helpers/FilesystemHelperTest.php
@@ -92,7 +92,7 @@ public function testDirectoryMapShowsHiddenFiles(): void
         $root = vfsStream::setup('root', null, $this->structure);
         $this->assertTrue($root->hasChild('foo'));
 
-        $this->assertSame($expected, directory_map(vfsStream::url('root'), false, true));
+        $this->assertSame($expected, directory_map(vfsStream::url('root'), 0, true));
     }
 
     public function testDirectoryMapLimitsRecursion(): void
diff --git a/tests/system/Helpers/TextHelperTest.php b/tests/system/Helpers/TextHelperTest.php
index 2af7f1387529..20647ec783b1 100755
--- a/tests/system/Helpers/TextHelperTest.php
+++ b/tests/system/Helpers/TextHelperTest.php
@@ -136,7 +136,7 @@ public function testIncrementString(): void
         $this->assertSame('file_5', increment_string('file_4'));
         $this->assertSame('file-5', increment_string('file-4', '-'));
         $this->assertSame('file-5', increment_string('file-4', '-'));
-        $this->assertSame('file-1', increment_string('file', '-', '1'));
+        $this->assertSame('file-1', increment_string('file', '-', 1));
         $this->assertSame('124', increment_string('123', ''));
     }