diff --git a/ChangeLog-11.3.md b/ChangeLog-11.3.md
index 59682c7c826..03c5094cd26 100644
--- a/ChangeLog-11.3.md
+++ b/ChangeLog-11.3.md
@@ -9,6 +9,7 @@ All notable changes of the PHPUnit 11.3 release series are documented in this fi
 * [#4584](https://github.com/sebastianbergmann/phpunit/issues/4584): `assertJsonStringEqualsJsonString()` considers objects with sequential numeric keys equal to arrays
 * [#4625](https://github.com/sebastianbergmann/phpunit/issues/4625): Generator yielding keys that are neither integer or string leads to hard-to-understand error message when used as data provider
 * [#4674](https://github.com/sebastianbergmann/phpunit/issues/4674): JSON assertions should treat objects as unordered
+* [#5891](https://github.com/sebastianbergmann/phpunit/issues/5891): `Callback` constraint does not handle variadic arguments correctly when used for mock object expectations
 * [#5929](https://github.com/sebastianbergmann/phpunit/issues/5929): TestDox output containing `$` at the beginning gets truncated when used with a data provider
 * [#5943](https://github.com/sebastianbergmann/phpunit/issues/5943): Tests configured to be in group(s) using the XML configuration file are also added to the `default` group
 
diff --git a/src/Framework/Constraint/Callback.php b/src/Framework/Constraint/Callback.php
index a3acef033d5..22d2d5099ef 100644
--- a/src/Framework/Constraint/Callback.php
+++ b/src/Framework/Constraint/Callback.php
@@ -9,6 +9,8 @@
  */
 namespace PHPUnit\Framework\Constraint;
 
+use ReflectionFunction;
+
 /**
  * @template CallbackInput of mixed
  *
@@ -37,6 +39,17 @@ public function toString(): string
         return 'is accepted by specified callback';
     }
 
+    public function isVariadic(): bool
+    {
+        foreach ((new ReflectionFunction($this->callback))->getParameters() as $parameter) {
+            if ($parameter->isVariadic()) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
     /**
      * Evaluates the constraint for parameter $value. Returns true if the
      * constraint is met, false otherwise.
@@ -45,6 +58,10 @@ public function toString(): string
      */
     protected function matches(mixed $other): bool
     {
+        if ($this->isVariadic()) {
+            return ($this->callback)(...$other);
+        }
+
         return ($this->callback)($other);
     }
 }
diff --git a/src/Framework/MockObject/Generator/MockMethod.php b/src/Framework/MockObject/Generator/MockMethod.php
index 9ce363824a7..0514500b9dd 100644
--- a/src/Framework/MockObject/Generator/MockMethod.php
+++ b/src/Framework/MockObject/Generator/MockMethod.php
@@ -17,6 +17,7 @@
 use function preg_match;
 use function preg_replace;
 use function sprintf;
+use function str_contains;
 use function strlen;
 use function strpos;
 use function substr;
@@ -211,13 +212,21 @@ public function generateCode(): string
 
         $template = $this->loadTemplate($templateFile);
 
+        $argumentsCount = 0;
+
+        if (str_contains($this->argumentsForCall, '...')) {
+            $argumentsCount = null;
+        } elseif (!empty($this->argumentsForCall)) {
+            $argumentsCount = substr_count($this->argumentsForCall, ',') + 1;
+        }
+
         $template->setVar(
             [
                 'arguments_decl'     => $this->argumentsForDeclaration,
                 'arguments_call'     => $this->argumentsForCall,
                 'return_declaration' => !empty($this->returnType->asString()) ? (': ' . $this->returnType->asString()) : '',
                 'return_type'        => $this->returnType->asString(),
-                'arguments_count'    => !empty($this->argumentsForCall) ? substr_count($this->argumentsForCall, ',') + 1 : 0,
+                'arguments_count'    => $argumentsCount,
                 'class_name'         => $this->className,
                 'method_name'        => $this->methodName,
                 'modifier'           => $this->modifier,
diff --git a/src/Framework/MockObject/Generator/templates/doubled_method.tpl b/src/Framework/MockObject/Generator/templates/doubled_method.tpl
index 8ecd412c213..1b1b663feff 100644
--- a/src/Framework/MockObject/Generator/templates/doubled_method.tpl
+++ b/src/Framework/MockObject/Generator/templates/doubled_method.tpl
@@ -17,7 +17,7 @@
         $__phpunit_arguments = [{arguments_call}];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > {arguments_count}) {
+        if ({arguments_count} !== null && $__phpunit_count > {arguments_count}) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = {arguments_count}; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/src/Framework/MockObject/Runtime/Rule/Parameters.php b/src/Framework/MockObject/Runtime/Rule/Parameters.php
index 0b980fe8c77..ee6aa1c7351 100644
--- a/src/Framework/MockObject/Runtime/Rule/Parameters.php
+++ b/src/Framework/MockObject/Runtime/Rule/Parameters.php
@@ -12,6 +12,7 @@
 use function count;
 use function sprintf;
 use Exception;
+use PHPUnit\Framework\Constraint\Callback;
 use PHPUnit\Framework\Constraint\Constraint;
 use PHPUnit\Framework\Constraint\IsAnything;
 use PHPUnit\Framework\Constraint\IsEqual;
@@ -110,8 +111,13 @@ private function doVerify(): bool
         }
 
         foreach ($this->parameters as $i => $parameter) {
+            if ($parameter instanceof Callback && $parameter->isVariadic()) {
+                $other = $this->invocation->parameters();
+            } else {
+                $other = $this->invocation->parameters()[$i];
+            }
             $parameter->evaluate(
-                $this->invocation->parameters()[$i],
+                $other,
                 sprintf(
                     'Parameter %s for invocation %s does not match expected ' .
                     'value.',
diff --git a/tests/end-to-end/mock-objects/generator/232.phpt b/tests/end-to-end/mock-objects/generator/232.phpt
index d59ae530146..e875d5298b7 100644
--- a/tests/end-to-end/mock-objects/generator/232.phpt
+++ b/tests/end-to-end/mock-objects/generator/232.phpt
@@ -82,7 +82,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/3154_namespaced_constant_resolving.phpt b/tests/end-to-end/mock-objects/generator/3154_namespaced_constant_resolving.phpt
index 24dfee4fb52..7a11767d630 100644
--- a/tests/end-to-end/mock-objects/generator/3154_namespaced_constant_resolving.phpt
+++ b/tests/end-to-end/mock-objects/generator/3154_namespaced_constant_resolving.phpt
@@ -67,7 +67,7 @@ class Issue3154Mock extends Is\Namespaced\Issue3154 implements PHPUnit\Framework
         $__phpunit_arguments = [$i, $j, $v, $z];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 4) {
+        if (4 !== null && $__phpunit_count > 4) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 4; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/3967.phpt b/tests/end-to-end/mock-objects/generator/3967.phpt
index 2ba1339231e..89e13dc72c8 100644
--- a/tests/end-to-end/mock-objects/generator/3967.phpt
+++ b/tests/end-to-end/mock-objects/generator/3967.phpt
@@ -55,7 +55,7 @@ class MockBaz extends Exception implements Baz, PHPUnit\Framework\MockObject\Moc
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/397.phpt b/tests/end-to-end/mock-objects/generator/397.phpt
index a4c2619700d..17d07b18ba9 100644
--- a/tests/end-to-end/mock-objects/generator/397.phpt
+++ b/tests/end-to-end/mock-objects/generator/397.phpt
@@ -53,7 +53,7 @@ class MockC extends C implements PHPUnit\Framework\MockObject\MockObjectInternal
         $__phpunit_arguments = [$other];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/4139.phpt b/tests/end-to-end/mock-objects/generator/4139.phpt
index 04caf588fba..4d01e3d1c93 100644
--- a/tests/end-to-end/mock-objects/generator/4139.phpt
+++ b/tests/end-to-end/mock-objects/generator/4139.phpt
@@ -42,7 +42,7 @@ class %s implements PHPUnit\Framework\MockObject\MockObjectInternal, InterfaceWi
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/abstract_class.phpt b/tests/end-to-end/mock-objects/generator/abstract_class.phpt
index a1856f71419..f984809f35b 100644
--- a/tests/end-to-end/mock-objects/generator/abstract_class.phpt
+++ b/tests/end-to-end/mock-objects/generator/abstract_class.phpt
@@ -57,7 +57,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
@@ -94,7 +94,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
@@ -131,7 +131,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/class.phpt b/tests/end-to-end/mock-objects/generator/class.phpt
index b855d4ef5ec..4b387312dc7 100644
--- a/tests/end-to-end/mock-objects/generator/class.phpt
+++ b/tests/end-to-end/mock-objects/generator/class.phpt
@@ -57,7 +57,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [$foo];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
@@ -94,7 +94,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [$foo];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/class_nonexistent_method.phpt b/tests/end-to-end/mock-objects/generator/class_nonexistent_method.phpt
index 0a4b6e22de4..ed277512b86 100644
--- a/tests/end-to-end/mock-objects/generator/class_nonexistent_method.phpt
+++ b/tests/end-to-end/mock-objects/generator/class_nonexistent_method.phpt
@@ -53,7 +53,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/class_partial.phpt b/tests/end-to-end/mock-objects/generator/class_partial.phpt
index 9608e262356..1d98d31a7cd 100644
--- a/tests/end-to-end/mock-objects/generator/class_partial.phpt
+++ b/tests/end-to-end/mock-objects/generator/class_partial.phpt
@@ -57,7 +57,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [$foo];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/class_with_deprecated_method.phpt b/tests/end-to-end/mock-objects/generator/class_with_deprecated_method.phpt
index d6b0d09986c..b56f4929588 100644
--- a/tests/end-to-end/mock-objects/generator/class_with_deprecated_method.phpt
+++ b/tests/end-to-end/mock-objects/generator/class_with_deprecated_method.phpt
@@ -59,7 +59,7 @@ class MockFoo extends ClassWithDeprecatedMethod implements PHPUnit\Framework\Moc
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/class_with_method_named_method.phpt b/tests/end-to-end/mock-objects/generator/class_with_method_named_method.phpt
index 99fad68c024..70aa4a42f47 100644
--- a/tests/end-to-end/mock-objects/generator/class_with_method_named_method.phpt
+++ b/tests/end-to-end/mock-objects/generator/class_with_method_named_method.phpt
@@ -52,7 +52,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/class_with_method_with_nullable_typehinted_variadic_arguments.phpt b/tests/end-to-end/mock-objects/generator/class_with_method_with_nullable_typehinted_variadic_arguments.phpt
index d689aee8a68..ad7bce6ae64 100644
--- a/tests/end-to-end/mock-objects/generator/class_with_method_with_nullable_typehinted_variadic_arguments.phpt
+++ b/tests/end-to-end/mock-objects/generator/class_with_method_with_nullable_typehinted_variadic_arguments.phpt
@@ -53,7 +53,7 @@ class MockFoo extends ClassWithMethodWithNullableTypehintedVariadicArguments imp
         $__phpunit_arguments = [$a];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/class_with_method_with_typehinted_variadic_arguments.phpt b/tests/end-to-end/mock-objects/generator/class_with_method_with_typehinted_variadic_arguments.phpt
index ef939db74c1..4e4d8e3b9e8 100644
--- a/tests/end-to-end/mock-objects/generator/class_with_method_with_typehinted_variadic_arguments.phpt
+++ b/tests/end-to-end/mock-objects/generator/class_with_method_with_typehinted_variadic_arguments.phpt
@@ -53,7 +53,7 @@ class MockFoo extends ClassWithMethodWithTypehintedVariadicArguments implements
         $__phpunit_arguments = [$a];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/class_with_method_with_variadic_arguments.phpt b/tests/end-to-end/mock-objects/generator/class_with_method_with_variadic_arguments.phpt
index a5ad0eeee73..077cdc3ba8e 100644
--- a/tests/end-to-end/mock-objects/generator/class_with_method_with_variadic_arguments.phpt
+++ b/tests/end-to-end/mock-objects/generator/class_with_method_with_variadic_arguments.phpt
@@ -53,7 +53,7 @@ class MockFoo extends ClassWithMethodWithVariadicArguments implements PHPUnit\Fr
         $__phpunit_arguments = [$a];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/constant_as_parameter_default_value.phpt b/tests/end-to-end/mock-objects/generator/constant_as_parameter_default_value.phpt
index 7ddfc743644..6980cdf3a68 100644
--- a/tests/end-to-end/mock-objects/generator/constant_as_parameter_default_value.phpt
+++ b/tests/end-to-end/mock-objects/generator/constant_as_parameter_default_value.phpt
@@ -53,7 +53,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [$baz];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/interface.phpt b/tests/end-to-end/mock-objects/generator/interface.phpt
index d6e78304899..e495955594e 100644
--- a/tests/end-to-end/mock-objects/generator/interface.phpt
+++ b/tests/end-to-end/mock-objects/generator/interface.phpt
@@ -51,7 +51,7 @@ class MockFoo implements PHPUnit\Framework\MockObject\MockObjectInternal, Foo
         $__phpunit_arguments = [$foo];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/invocation_object_clone_object.phpt b/tests/end-to-end/mock-objects/generator/invocation_object_clone_object.phpt
index bf75e92a725..6c9ef95428c 100644
--- a/tests/end-to-end/mock-objects/generator/invocation_object_clone_object.phpt
+++ b/tests/end-to-end/mock-objects/generator/invocation_object_clone_object.phpt
@@ -58,7 +58,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [$foo];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
@@ -95,7 +95,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [$foo];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/namespaced_class.phpt b/tests/end-to-end/mock-objects/generator/namespaced_class.phpt
index 80b3f742388..f976c2c2e8c 100644
--- a/tests/end-to-end/mock-objects/generator/namespaced_class.phpt
+++ b/tests/end-to-end/mock-objects/generator/namespaced_class.phpt
@@ -59,7 +59,7 @@ class MockFoo extends NS\Foo implements PHPUnit\Framework\MockObject\MockObjectI
         $__phpunit_arguments = [$foo];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
@@ -96,7 +96,7 @@ class MockFoo extends NS\Foo implements PHPUnit\Framework\MockObject\MockObjectI
         $__phpunit_arguments = [$foo];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/namespaced_class_partial.phpt b/tests/end-to-end/mock-objects/generator/namespaced_class_partial.phpt
index 5849422422c..25a11df238f 100644
--- a/tests/end-to-end/mock-objects/generator/namespaced_class_partial.phpt
+++ b/tests/end-to-end/mock-objects/generator/namespaced_class_partial.phpt
@@ -59,7 +59,7 @@ class MockFoo extends NS\Foo implements PHPUnit\Framework\MockObject\MockObjectI
         $__phpunit_arguments = [$foo];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/namespaced_interface.phpt b/tests/end-to-end/mock-objects/generator/namespaced_interface.phpt
index 3df7ddab0df..954c8badf65 100644
--- a/tests/end-to-end/mock-objects/generator/namespaced_interface.phpt
+++ b/tests/end-to-end/mock-objects/generator/namespaced_interface.phpt
@@ -53,7 +53,7 @@ class MockFoo implements PHPUnit\Framework\MockObject\MockObjectInternal, NS\Foo
         $__phpunit_arguments = [$foo];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/nullable_types.phpt b/tests/end-to-end/mock-objects/generator/nullable_types.phpt
index d831a0d2c67..be1d240d85d 100644
--- a/tests/end-to-end/mock-objects/generator/nullable_types.phpt
+++ b/tests/end-to-end/mock-objects/generator/nullable_types.phpt
@@ -53,7 +53,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [$x];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/nullable_union_type_parameter.phpt b/tests/end-to-end/mock-objects/generator/nullable_union_type_parameter.phpt
index bc181a61911..678c0aa8c0e 100644
--- a/tests/end-to-end/mock-objects/generator/nullable_union_type_parameter.phpt
+++ b/tests/end-to-end/mock-objects/generator/nullable_union_type_parameter.phpt
@@ -53,7 +53,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [$baz, $other];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 2) {
+        if (2 !== null && $__phpunit_count > 2) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 2; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/nullable_union_type_return.phpt b/tests/end-to-end/mock-objects/generator/nullable_union_type_return.phpt
index a92cb119eac..a5fbb196402 100644
--- a/tests/end-to-end/mock-objects/generator/nullable_union_type_return.phpt
+++ b/tests/end-to-end/mock-objects/generator/nullable_union_type_return.phpt
@@ -53,7 +53,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/parameter_dnf.phpt b/tests/end-to-end/mock-objects/generator/parameter_dnf.phpt
index 35ba79bdc27..2e662a2b9d3 100644
--- a/tests/end-to-end/mock-objects/generator/parameter_dnf.phpt
+++ b/tests/end-to-end/mock-objects/generator/parameter_dnf.phpt
@@ -61,7 +61,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [$baz];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/parameter_false.phpt b/tests/end-to-end/mock-objects/generator/parameter_false.phpt
index 9f76d1dff26..12977e3fe6f 100644
--- a/tests/end-to-end/mock-objects/generator/parameter_false.phpt
+++ b/tests/end-to-end/mock-objects/generator/parameter_false.phpt
@@ -51,7 +51,7 @@ class MockFoo implements PHPUnit\Framework\MockObject\MockObjectInternal, Foo
         $__phpunit_arguments = [$baz];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/parameter_intersection.phpt b/tests/end-to-end/mock-objects/generator/parameter_intersection.phpt
index aff259a262d..c26458cffbc 100644
--- a/tests/end-to-end/mock-objects/generator/parameter_intersection.phpt
+++ b/tests/end-to-end/mock-objects/generator/parameter_intersection.phpt
@@ -61,7 +61,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [$baz];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/parameter_null.phpt b/tests/end-to-end/mock-objects/generator/parameter_null.phpt
index 553b12517e1..30dd0b1c698 100644
--- a/tests/end-to-end/mock-objects/generator/parameter_null.phpt
+++ b/tests/end-to-end/mock-objects/generator/parameter_null.phpt
@@ -51,7 +51,7 @@ class MockFoo implements PHPUnit\Framework\MockObject\MockObjectInternal, Foo
         $__phpunit_arguments = [$baz];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/parameter_true.phpt b/tests/end-to-end/mock-objects/generator/parameter_true.phpt
index 07f1ae0ab8f..7dd44d5f61f 100644
--- a/tests/end-to-end/mock-objects/generator/parameter_true.phpt
+++ b/tests/end-to-end/mock-objects/generator/parameter_true.phpt
@@ -51,7 +51,7 @@ class MockFoo implements PHPUnit\Framework\MockObject\MockObjectInternal, Foo
         $__phpunit_arguments = [$baz];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/parameter_union.phpt b/tests/end-to-end/mock-objects/generator/parameter_union.phpt
index f716a1b9eb2..2a1d75a5847 100644
--- a/tests/end-to-end/mock-objects/generator/parameter_union.phpt
+++ b/tests/end-to-end/mock-objects/generator/parameter_union.phpt
@@ -53,7 +53,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [$baz, $other];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 2) {
+        if (2 !== null && $__phpunit_count > 2) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 2; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/return_type_declarations_closure.phpt b/tests/end-to-end/mock-objects/generator/return_type_declarations_closure.phpt
index e57b53afe96..1c2729060e6 100644
--- a/tests/end-to-end/mock-objects/generator/return_type_declarations_closure.phpt
+++ b/tests/end-to-end/mock-objects/generator/return_type_declarations_closure.phpt
@@ -51,7 +51,7 @@ class MockFoo implements PHPUnit\Framework\MockObject\MockObjectInternal, Foo
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/return_type_declarations_dnf.phpt b/tests/end-to-end/mock-objects/generator/return_type_declarations_dnf.phpt
index 9610d24e23b..5734f26c9de 100644
--- a/tests/end-to-end/mock-objects/generator/return_type_declarations_dnf.phpt
+++ b/tests/end-to-end/mock-objects/generator/return_type_declarations_dnf.phpt
@@ -61,7 +61,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/return_type_declarations_false.phpt b/tests/end-to-end/mock-objects/generator/return_type_declarations_false.phpt
index 033cfbcc56c..d27ae2954df 100644
--- a/tests/end-to-end/mock-objects/generator/return_type_declarations_false.phpt
+++ b/tests/end-to-end/mock-objects/generator/return_type_declarations_false.phpt
@@ -51,7 +51,7 @@ class MockFoo implements PHPUnit\Framework\MockObject\MockObjectInternal, Foo
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/return_type_declarations_final.phpt b/tests/end-to-end/mock-objects/generator/return_type_declarations_final.phpt
index d8cdfbeed45..b3535650a09 100644
--- a/tests/end-to-end/mock-objects/generator/return_type_declarations_final.phpt
+++ b/tests/end-to-end/mock-objects/generator/return_type_declarations_final.phpt
@@ -58,7 +58,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/return_type_declarations_generator.phpt b/tests/end-to-end/mock-objects/generator/return_type_declarations_generator.phpt
index d530707cd2f..c602a9f00e9 100644
--- a/tests/end-to-end/mock-objects/generator/return_type_declarations_generator.phpt
+++ b/tests/end-to-end/mock-objects/generator/return_type_declarations_generator.phpt
@@ -51,7 +51,7 @@ class MockFoo implements PHPUnit\Framework\MockObject\MockObjectInternal, Foo
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/return_type_declarations_intersection.phpt b/tests/end-to-end/mock-objects/generator/return_type_declarations_intersection.phpt
index cd3afcad7ba..30963713c94 100644
--- a/tests/end-to-end/mock-objects/generator/return_type_declarations_intersection.phpt
+++ b/tests/end-to-end/mock-objects/generator/return_type_declarations_intersection.phpt
@@ -61,7 +61,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/return_type_declarations_never.phpt b/tests/end-to-end/mock-objects/generator/return_type_declarations_never.phpt
index 165958536bf..af8e1547818 100644
--- a/tests/end-to-end/mock-objects/generator/return_type_declarations_never.phpt
+++ b/tests/end-to-end/mock-objects/generator/return_type_declarations_never.phpt
@@ -51,7 +51,7 @@ class MockFoo implements PHPUnit\Framework\MockObject\MockObjectInternal, Foo
         $__phpunit_arguments = [$baz];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/return_type_declarations_null.phpt b/tests/end-to-end/mock-objects/generator/return_type_declarations_null.phpt
index 9d248560b2d..4ce391ad6dc 100644
--- a/tests/end-to-end/mock-objects/generator/return_type_declarations_null.phpt
+++ b/tests/end-to-end/mock-objects/generator/return_type_declarations_null.phpt
@@ -51,7 +51,7 @@ class MockFoo implements PHPUnit\Framework\MockObject\MockObjectInternal, Foo
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/return_type_declarations_nullable.phpt b/tests/end-to-end/mock-objects/generator/return_type_declarations_nullable.phpt
index 72c0305dbc0..8c15f67b0a9 100644
--- a/tests/end-to-end/mock-objects/generator/return_type_declarations_nullable.phpt
+++ b/tests/end-to-end/mock-objects/generator/return_type_declarations_nullable.phpt
@@ -51,7 +51,7 @@ class MockFoo implements PHPUnit\Framework\MockObject\MockObjectInternal, Foo
         $__phpunit_arguments = [$baz];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/return_type_declarations_object_method.phpt b/tests/end-to-end/mock-objects/generator/return_type_declarations_object_method.phpt
index 00a866b83fb..263d278b80e 100644
--- a/tests/end-to-end/mock-objects/generator/return_type_declarations_object_method.phpt
+++ b/tests/end-to-end/mock-objects/generator/return_type_declarations_object_method.phpt
@@ -54,7 +54,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [$baz];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/return_type_declarations_parent.phpt b/tests/end-to-end/mock-objects/generator/return_type_declarations_parent.phpt
index 2b66496867e..6d6de9565a3 100644
--- a/tests/end-to-end/mock-objects/generator/return_type_declarations_parent.phpt
+++ b/tests/end-to-end/mock-objects/generator/return_type_declarations_parent.phpt
@@ -58,7 +58,7 @@ class MockBar extends Bar implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/return_type_declarations_self.phpt b/tests/end-to-end/mock-objects/generator/return_type_declarations_self.phpt
index ac6a40dafee..8a2c961e7c3 100644
--- a/tests/end-to-end/mock-objects/generator/return_type_declarations_self.phpt
+++ b/tests/end-to-end/mock-objects/generator/return_type_declarations_self.phpt
@@ -51,7 +51,7 @@ class MockFoo implements PHPUnit\Framework\MockObject\MockObjectInternal, Foo
         $__phpunit_arguments = [$baz];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/return_type_declarations_static.phpt b/tests/end-to-end/mock-objects/generator/return_type_declarations_static.phpt
index 0df54517b8f..29d31f457e9 100644
--- a/tests/end-to-end/mock-objects/generator/return_type_declarations_static.phpt
+++ b/tests/end-to-end/mock-objects/generator/return_type_declarations_static.phpt
@@ -61,7 +61,7 @@ class MockClassWithStaticReturnTypes extends ClassWithStaticReturnTypes implemen
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
@@ -98,7 +98,7 @@ class MockClassWithStaticReturnTypes extends ClassWithStaticReturnTypes implemen
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
@@ -135,7 +135,7 @@ class MockClassWithStaticReturnTypes extends ClassWithStaticReturnTypes implemen
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/return_type_declarations_true.phpt b/tests/end-to-end/mock-objects/generator/return_type_declarations_true.phpt
index 1e26dca6cfe..13deb66946c 100644
--- a/tests/end-to-end/mock-objects/generator/return_type_declarations_true.phpt
+++ b/tests/end-to-end/mock-objects/generator/return_type_declarations_true.phpt
@@ -51,7 +51,7 @@ class MockFoo implements PHPUnit\Framework\MockObject\MockObjectInternal, Foo
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/return_type_declarations_union.phpt b/tests/end-to-end/mock-objects/generator/return_type_declarations_union.phpt
index 461fcfd8110..74f1256626d 100644
--- a/tests/end-to-end/mock-objects/generator/return_type_declarations_union.phpt
+++ b/tests/end-to-end/mock-objects/generator/return_type_declarations_union.phpt
@@ -53,7 +53,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/return_type_declarations_void.phpt b/tests/end-to-end/mock-objects/generator/return_type_declarations_void.phpt
index faa46e75cdf..3886cc01c00 100644
--- a/tests/end-to-end/mock-objects/generator/return_type_declarations_void.phpt
+++ b/tests/end-to-end/mock-objects/generator/return_type_declarations_void.phpt
@@ -51,7 +51,7 @@ class MockFoo implements PHPUnit\Framework\MockObject\MockObjectInternal, Foo
         $__phpunit_arguments = [$baz];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/generator/scalar_type_declarations.phpt b/tests/end-to-end/mock-objects/generator/scalar_type_declarations.phpt
index 154640d91b1..67539df61f7 100644
--- a/tests/end-to-end/mock-objects/generator/scalar_type_declarations.phpt
+++ b/tests/end-to-end/mock-objects/generator/scalar_type_declarations.phpt
@@ -53,7 +53,7 @@ class MockFoo extends Foo implements PHPUnit\Framework\MockObject\MockObjectInte
         $__phpunit_arguments = [$baz];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/clone_method_arguments.phpt b/tests/end-to-end/mock-objects/mock-method/clone_method_arguments.phpt
index 50ab1870d1e..e5636f6f4d9 100644
--- a/tests/end-to-end/mock-objects/mock-method/clone_method_arguments.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/clone_method_arguments.phpt
@@ -39,7 +39,7 @@ print $code;
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/deprecated_with_description.phpt b/tests/end-to-end/mock-objects/mock-method/deprecated_with_description.phpt
index 6ccdc32901b..f7d0354de0f 100644
--- a/tests/end-to-end/mock-objects/mock-method/deprecated_with_description.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/deprecated_with_description.phpt
@@ -44,7 +44,7 @@ public function bar()
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/deprecated_without_description.phpt b/tests/end-to-end/mock-objects/mock-method/deprecated_without_description.phpt
index e2a387ecfe0..1f36d5525ab 100644
--- a/tests/end-to-end/mock-objects/mock-method/deprecated_without_description.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/deprecated_without_description.phpt
@@ -44,7 +44,7 @@ public function bar()
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/private_method.phpt b/tests/end-to-end/mock-objects/mock-method/private_method.phpt
index f844e12da35..4b5cacfd7b0 100644
--- a/tests/end-to-end/mock-objects/mock-method/private_method.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/private_method.phpt
@@ -39,7 +39,7 @@ private function bar()
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/protected_method.phpt b/tests/end-to-end/mock-objects/mock-method/protected_method.phpt
index f8f6d82999e..40a93252247 100644
--- a/tests/end-to-end/mock-objects/mock-method/protected_method.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/protected_method.phpt
@@ -39,7 +39,7 @@ protected function bar()
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/return_by_reference.phpt b/tests/end-to-end/mock-objects/mock-method/return_by_reference.phpt
index 51156da0c97..531d7be25eb 100644
--- a/tests/end-to-end/mock-objects/mock-method/return_by_reference.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/return_by_reference.phpt
@@ -39,7 +39,7 @@ public function &bar()
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/return_by_reference_with_return_type.phpt b/tests/end-to-end/mock-objects/mock-method/return_by_reference_with_return_type.phpt
index 3baa0687d02..637cb2debe8 100644
--- a/tests/end-to-end/mock-objects/mock-method/return_by_reference_with_return_type.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/return_by_reference_with_return_type.phpt
@@ -39,7 +39,7 @@ public function &bar(): string
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/return_type.phpt b/tests/end-to-end/mock-objects/mock-method/return_type.phpt
index 9d44056ae7b..0ae04dc0dc9 100644
--- a/tests/end-to-end/mock-objects/mock-method/return_type.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/return_type.phpt
@@ -39,7 +39,7 @@ public function bar(): string
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/return_type_parent.phpt b/tests/end-to-end/mock-objects/mock-method/return_type_parent.phpt
index 7fd0b2734a6..5d896a32476 100644
--- a/tests/end-to-end/mock-objects/mock-method/return_type_parent.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/return_type_parent.phpt
@@ -43,7 +43,7 @@ public function bar(): Baz
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/return_type_self.phpt b/tests/end-to-end/mock-objects/mock-method/return_type_self.phpt
index 7ccd57a45ac..f2faa58ea8d 100644
--- a/tests/end-to-end/mock-objects/mock-method/return_type_self.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/return_type_self.phpt
@@ -39,7 +39,7 @@ public function bar(): Foo
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/with_argument.phpt b/tests/end-to-end/mock-objects/mock-method/with_argument.phpt
index 76b527ea4e4..3d2c6d84044 100644
--- a/tests/end-to-end/mock-objects/mock-method/with_argument.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/with_argument.phpt
@@ -39,7 +39,7 @@ private function bar($arg)
         $__phpunit_arguments = [$arg];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/with_argument_default.phpt b/tests/end-to-end/mock-objects/mock-method/with_argument_default.phpt
index aaac640b99c..3cb44b0d3f0 100644
--- a/tests/end-to-end/mock-objects/mock-method/with_argument_default.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/with_argument_default.phpt
@@ -39,7 +39,7 @@ private function bar($arg = false)
         $__phpunit_arguments = [$arg];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/with_argument_default_constant.phpt b/tests/end-to-end/mock-objects/mock-method/with_argument_default_constant.phpt
index e7d79d5330d..25a91c71c54 100644
--- a/tests/end-to-end/mock-objects/mock-method/with_argument_default_constant.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/with_argument_default_constant.phpt
@@ -44,7 +44,7 @@ private function bar($a = 1, $b = 2, $c = 3, $d = 4)
         $__phpunit_arguments = [$a, $b, $c, $d];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 4) {
+        if (4 !== null && $__phpunit_count > 4) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 4; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/with_argument_default_new_expression.phpt b/tests/end-to-end/mock-objects/mock-method/with_argument_default_new_expression.phpt
index 94ef6dcfd99..57448e2cbe9 100644
--- a/tests/end-to-end/mock-objects/mock-method/with_argument_default_new_expression.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/with_argument_default_new_expression.phpt
@@ -46,7 +46,7 @@ public function method(Foo $foo = new \Foo(1, 2, 3))
         $__phpunit_arguments = [$foo];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/with_argument_default_null.phpt b/tests/end-to-end/mock-objects/mock-method/with_argument_default_null.phpt
index 07fe364b31a..9c9489898db 100644
--- a/tests/end-to-end/mock-objects/mock-method/with_argument_default_null.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/with_argument_default_null.phpt
@@ -39,7 +39,7 @@ private function bar($arg = NULL)
         $__phpunit_arguments = [$arg];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/with_argument_nullable.phpt b/tests/end-to-end/mock-objects/mock-method/with_argument_nullable.phpt
index 6a7b2d35a7e..ca05df39b60 100644
--- a/tests/end-to-end/mock-objects/mock-method/with_argument_nullable.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/with_argument_nullable.phpt
@@ -39,7 +39,7 @@ private function bar(?string $arg)
         $__phpunit_arguments = [$arg];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/with_argument_reference.phpt b/tests/end-to-end/mock-objects/mock-method/with_argument_reference.phpt
index 149dc6adfea..31ec140b15a 100644
--- a/tests/end-to-end/mock-objects/mock-method/with_argument_reference.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/with_argument_reference.phpt
@@ -39,7 +39,7 @@ private function bar(&$arg)
         $__phpunit_arguments = [&$arg];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/with_argument_typed_array.phpt b/tests/end-to-end/mock-objects/mock-method/with_argument_typed_array.phpt
index 08f5391e64c..228cfb4e77a 100644
--- a/tests/end-to-end/mock-objects/mock-method/with_argument_typed_array.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/with_argument_typed_array.phpt
@@ -39,7 +39,7 @@ private function bar(array $arg)
         $__phpunit_arguments = [$arg];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/with_argument_typed_callable.phpt b/tests/end-to-end/mock-objects/mock-method/with_argument_typed_callable.phpt
index d94e276f681..c45de6724c1 100644
--- a/tests/end-to-end/mock-objects/mock-method/with_argument_typed_callable.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/with_argument_typed_callable.phpt
@@ -39,7 +39,7 @@ private function bar(callable $arg)
         $__phpunit_arguments = [$arg];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/with_argument_typed_class.phpt b/tests/end-to-end/mock-objects/mock-method/with_argument_typed_class.phpt
index 54375f6806b..77318e54853 100644
--- a/tests/end-to-end/mock-objects/mock-method/with_argument_typed_class.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/with_argument_typed_class.phpt
@@ -39,7 +39,7 @@ private function bar(Exception $arg)
         $__phpunit_arguments = [$arg];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/with_argument_typed_scalar.phpt b/tests/end-to-end/mock-objects/mock-method/with_argument_typed_scalar.phpt
index a59f3871d18..4084f3c9c1e 100644
--- a/tests/end-to-end/mock-objects/mock-method/with_argument_typed_scalar.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/with_argument_typed_scalar.phpt
@@ -39,7 +39,7 @@ private function bar(string $arg)
         $__phpunit_arguments = [$arg];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/with_argument_typed_self.phpt b/tests/end-to-end/mock-objects/mock-method/with_argument_typed_self.phpt
index 4d7d5293807..b9571f2382a 100644
--- a/tests/end-to-end/mock-objects/mock-method/with_argument_typed_self.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/with_argument_typed_self.phpt
@@ -39,7 +39,7 @@ private function bar(Foo $arg)
         $__phpunit_arguments = [$arg];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/with_argument_typed_unkown_class.phpt b/tests/end-to-end/mock-objects/mock-method/with_argument_typed_unkown_class.phpt
index a0549f5ef08..980c4d85aa6 100644
--- a/tests/end-to-end/mock-objects/mock-method/with_argument_typed_unkown_class.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/with_argument_typed_unkown_class.phpt
@@ -39,7 +39,7 @@ private function bar(UnknownClass $arg)
         $__phpunit_arguments = [$arg];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 1) {
+        if (1 !== null && $__phpunit_count > 1) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 1; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/with_argument_typed_variadic.phpt b/tests/end-to-end/mock-objects/mock-method/with_argument_typed_variadic.phpt
index 3c2a792c356..5f2c4169cc5 100644
--- a/tests/end-to-end/mock-objects/mock-method/with_argument_typed_variadic.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/with_argument_typed_variadic.phpt
@@ -39,7 +39,7 @@ private function bar(string ...$args)
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/with_argument_variadic.phpt b/tests/end-to-end/mock-objects/mock-method/with_argument_variadic.phpt
index e4ce178d801..2c0e391e78d 100644
--- a/tests/end-to-end/mock-objects/mock-method/with_argument_variadic.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/with_argument_variadic.phpt
@@ -39,7 +39,7 @@ private function bar(...$args)
         $__phpunit_arguments = [];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 0) {
+        if (0 !== null && $__phpunit_count > 0) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/mock-objects/mock-method/with_arguments.phpt b/tests/end-to-end/mock-objects/mock-method/with_arguments.phpt
index 7cdbfa7adb7..70f029a734d 100644
--- a/tests/end-to-end/mock-objects/mock-method/with_arguments.phpt
+++ b/tests/end-to-end/mock-objects/mock-method/with_arguments.phpt
@@ -39,7 +39,7 @@ private function bar($arg1, $arg2)
         $__phpunit_arguments = [$arg1, $arg2];
         $__phpunit_count     = func_num_args();
 
-        if ($__phpunit_count > 2) {
+        if (2 !== null && $__phpunit_count > 2) {
             $__phpunit_arguments_tmp = func_get_args();
 
             for ($__phpunit_i = 2; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
diff --git a/tests/end-to-end/regression/5891.phpt b/tests/end-to-end/regression/5891.phpt
new file mode 100644
index 00000000000..934ea0944ae
--- /dev/null
+++ b/tests/end-to-end/regression/5891.phpt
@@ -0,0 +1,20 @@
+--TEST--
+https://github.com/sebastianbergmann/phpunit/issues/5891
+--FILE--
+<?php declare(strict_types=1);
+$_SERVER['argv'][] = '--do-not-cache-result';
+$_SERVER['argv'][] = '--no-configuration';
+$_SERVER['argv'][] = __DIR__ . '/5891/Issue5891Test.php';
+
+require_once __DIR__ . '/../../bootstrap.php';
+(new PHPUnit\TextUI\Application)->run($_SERVER['argv']);
+--EXPECTF--
+PHPUnit %s by Sebastian Bergmann and contributors.
+
+Runtime: %s
+
+..                                                                  2 / 2 (100%)
+
+Time: %s, Memory: %s MB
+
+OK (2 tests, 2 assertions)
diff --git a/tests/end-to-end/regression/5891/Issue5891Test.php b/tests/end-to-end/regression/5891/Issue5891Test.php
new file mode 100644
index 00000000000..d22c5ed846d
--- /dev/null
+++ b/tests/end-to-end/regression/5891/Issue5891Test.php
@@ -0,0 +1,55 @@
+<?php declare(strict_types=1);
+/*
+ * This file is part of PHPUnit.
+ *
+ * (c) Sebastian Bergmann <sebastian@phpunit.de>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+namespace PHPUnit\TestFixture\Issue5891;
+
+use PHPUnit\Framework\TestCase;
+
+final class Issue5891Test extends TestCase
+{
+    public function testVariadicParam(): void
+    {
+        $mock = $this->createMock(ArgumentList::class);
+        $mock
+            ->method('foo')
+            ->with($this->callback(static function (...$items): bool
+            {
+                self::assertSame([1, 2, 3], $items);
+
+                return true;
+            }));
+
+        $mock->foo(1, 2, 3);
+    }
+
+    public function testTwoParametersAndVariadicParam(): void
+    {
+        $mock = $this->createMock(TwoParametersAndArgumentList::class);
+        $mock
+            ->method('foo')
+            ->with($this->callback(static function (...$items): bool
+            {
+                self::assertSame(['1st', '2nd', '3rd', '4th'], $items);
+
+                return true;
+            }));
+
+        $mock->foo('1st', '2nd', '3rd', '4th');
+    }
+}
+
+interface ArgumentList
+{
+    public function foo(int ...$items): void;
+}
+
+interface TwoParametersAndArgumentList
+{
+    public function foo(string $first, string $second, string ...$rest): void;
+}