diff -uarN a/tests/ImportKeyTest.php b/tests/ImportKeyTest.php
--- a/tests/ImportKeyTest.php	2020-03-22 08:00:23.000000000 -0400
+++ b/tests/ImportKeyTest.php	2021-02-02 14:45:16.561963089 -0500
@@ -60,7 +60,7 @@
     // set up
     // {{{ setUp()
 
-    public function setUp()
+    public function setUp() :void
     {
         parent::setUp();
 
diff -uarN a/tests/KeyGeneratorTest.php b/tests/KeyGeneratorTest.php
--- a/tests/KeyGeneratorTest.php	2020-03-22 08:00:23.000000000 -0400
+++ b/tests/KeyGeneratorTest.php	2021-02-02 14:42:07.117718685 -0500
@@ -174,7 +174,7 @@
     // }}}
     // {{{ setUp()
 
-    public function setUp()
+    public function setUp() :void
     {
         parent::setUp();
         $this->generator = new Crypt_GPG_KeyGenerator($this->getOptions());
diff -uarN a/tests/TestCase.php b/tests/TestCase.php
--- a/tests/TestCase.php	2020-03-22 08:00:23.000000000 -0400
+++ b/tests/TestCase.php	2021-02-02 14:42:36.978387716 -0500
@@ -119,7 +119,7 @@
     // set up
     // {{{ setUp()
 
-    public function setUp()
+    public function setUp() :void
     {
         // load test configuration file if it exists
         $configFilename = __DIR__ . '/config.php';
@@ -567,7 +567,7 @@
     // }}}
     // {{{ tearDown()
 
-    public function tearDown()
+    public function tearDown() :void
     {
         unset($this->gpg);
 
