Added tests for methods with variadic arguments

tests/_files/ClassWithVariadicArgumentMethod.php

@@ -0,0 +1,20 @@
+<?php
+/*
+ * 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.
+ */
+
+/**
+ * A class with a method that takes a variadic argument.
+ */
+class ClassWithVariadicArgumentMethod
+{
+    public function foo(...$args)
+    {
+        return $args;
+    }
+}

tests/unit/Framework/MockObject/GeneratorTest.php

@@ -210,4 +210,44 @@ public function testMockingOfThrowable(): void
         $this->assertInstanceOf(Exception::class, $stub);
         $this->assertInstanceOf(MockObject::class, $stub);
     }
+
+    public function testVariadicArgumentsArePassedToOriginalMethod()
+    {
+        /** @var ClassWithVariadicArgumentMethod|MockObject $mock */
+        $mock = $this->generator->getMock(
+            ClassWithVariadicArgumentMethod::class,
+            [],
+            [],
+            '',
+            true,
+            false,
+            true,
+            false,
+            true
+        );
+
+        $arguments = [1, 'foo', false];
+        $this->assertSame($arguments, $mock->foo(...$arguments));
+    }
+
+    public function testVariadicArgumentsArePassedToMockedMethod()
+    {
+        /** @var ClassWithVariadicArgumentMethod|MockObject $mock */
+        $mock = $this->generator->getMock(
+            ClassWithVariadicArgumentMethod::class,
+            [],
+            [],
+            '',
+            true,
+            false,
+            true,
+            false,
+            false
+        );
+
+        $arguments = [1, 'foo', false];
+        $mock->expects($this->once())
+            ->method('foo')
+            ->with(...$arguments);
+    }
 }