diff --git a/tests/Core/File/GetMethodParametersTest.inc b/tests/Core/File/GetMethodParametersTest.inc
index 86eff8dd4a..e4d5bfca74 100644
--- a/tests/Core/File/GetMethodParametersTest.inc
+++ b/tests/Core/File/GetMethodParametersTest.inc
@@ -31,3 +31,10 @@ function myFunction($a = 10 & 20) {}
 
 /* testArrowFunction */
 fn(int $a, ...$b) => $b;
+
+/* testPHP8MixedTypeHint */
+function mixedTypeHint(mixed &...$var1) {}
+
+/* testPHP8MixedTypeHintNullable */
+// Intentional fatal error - nullability is not allowed with mixed, but that's not the concern of the method.
+function mixedTypeHintNullable(?Mixed $var1) {}
diff --git a/tests/Core/File/GetMethodParametersTest.php b/tests/Core/File/GetMethodParametersTest.php
index 1e8595da5c..f5d43c1a63 100644
--- a/tests/Core/File/GetMethodParametersTest.php
+++ b/tests/Core/File/GetMethodParametersTest.php
@@ -274,6 +274,50 @@ public function testArrowFunction()
     }//end testArrowFunction()
 
 
+    /**
+     * Verify recognition of PHP8 mixed type declaration.
+     *
+     * @return void
+     */
+    public function testPHP8MixedTypeHint()
+    {
+        $expected    = [];
+        $expected[0] = [
+            'name'              => '$var1',
+            'content'           => 'mixed &...$var1',
+            'pass_by_reference' => true,
+            'variable_length'   => true,
+            'type_hint'         => 'mixed',
+            'nullable_type'     => false,
+        ];
+
+        $this->getMethodParametersTestHelper('/* '.__FUNCTION__.' */', $expected);
+
+    }//end testPHP8MixedTypeHint()
+
+
+    /**
+     * Verify recognition of PHP8 mixed type declaration with nullability.
+     *
+     * @return void
+     */
+    public function testPHP8MixedTypeHintNullable()
+    {
+        $expected    = [];
+        $expected[0] = [
+            'name'              => '$var1',
+            'content'           => '?Mixed $var1',
+            'pass_by_reference' => false,
+            'variable_length'   => false,
+            'type_hint'         => '?Mixed',
+            'nullable_type'     => true,
+        ];
+
+        $this->getMethodParametersTestHelper('/* '.__FUNCTION__.' */', $expected);
+
+    }//end testPHP8MixedTypeHintNullable()
+
+
     /**
      * Test helper.
      *