diff --git a/src/PresenterMapping/PresenterMapper.php b/src/PresenterMapping/PresenterMapper.php
index df3136e..8ad96ec 100644
--- a/src/PresenterMapping/PresenterMapper.php
+++ b/src/PresenterMapping/PresenterMapper.php
@@ -78,10 +78,12 @@ public function setModuleMapping(string $module, $mask): self
         } elseif (is_string($mask)) {
             $m = Strings::match($mask, '#^\\\\?([\w\\\\]*\\\\)?(\w*\*\w*?\\\\)?([\w\\\\]*\*\w*)\z#');
             if ($m === null) {
+                $module = $module === '' ? '*' : $module;
                 throw new \InvalidArgumentException("Invalid mapping mask '$mask' for module '$module'.");
             }
-            $this->moduleMapping[$module] = [$m[1], $m[2] ?? '*Module\\', $m[3]];
+            $this->moduleMapping[$module] = [$m[1], $m[2] !== '' ? $m[2] : '*Module\\', $m[3]];
         } else {
+            $module = $module === '' ? '*' : $module;
             throw new \InvalidArgumentException("Invalid mapping mask for module '$module'.");
         }
         uksort(
diff --git a/tests/PresenterMapping/PresenterFactoryTest.phpt b/tests/PresenterMapping/PresenterFactoryTest.phpt
new file mode 100644
index 0000000..65e069b
--- /dev/null
+++ b/tests/PresenterMapping/PresenterFactoryTest.phpt
@@ -0,0 +1,104 @@
+<?php
+declare(strict_types = 1);
+
+namespace NepadaTests\PresenterMapping;
+
+use Nepada\PresenterMapping\PresenterFactory;
+use Nepada\PresenterMapping\PresenterMapper;
+use NepadaTests\TestCase;
+use Tester\Assert;
+
+require_once __DIR__ . '/../bootstrap.php';
+
+
+/**
+ * Based on Nette test cases to ensure compatibility with default implementation.
+ *
+ * @testCase
+ */
+class PresenterFactoryTest extends TestCase
+{
+
+    private PresenterFactory $presenterFactory;
+
+    protected function setUp(): void
+    {
+        $mapper = new PresenterMapper();
+        $this->presenterFactory = new PresenterFactory($mapper);
+    }
+
+    public function testStandardMapping(): void
+    {
+        $factory = $this->presenterFactory;
+        $factory->setMapping([
+            'Foo2' => 'App2\*\*Presenter',
+            'Foo3' => 'My\App\*Mod\*Presenter',
+        ]);
+
+        Assert::same('FooPresenter', $factory->formatPresenterClass('Foo'));
+        Assert::same('FooModule\BarPresenter', $factory->formatPresenterClass('Foo:Bar'));
+        Assert::same('FooModule\BarModule\BazPresenter', $factory->formatPresenterClass('Foo:Bar:Baz'));
+
+        Assert::same('Foo2Presenter', $factory->formatPresenterClass('Foo2'));
+        Assert::same('App2\BarPresenter', $factory->formatPresenterClass('Foo2:Bar'));
+        Assert::same('App2\Bar\BazPresenter', $factory->formatPresenterClass('Foo2:Bar:Baz'));
+
+        Assert::same('My\App\BarPresenter', $factory->formatPresenterClass('Foo3:Bar'));
+        Assert::same('My\App\BarMod\BazPresenter', $factory->formatPresenterClass('Foo3:Bar:Baz'));
+
+        Assert::same('NetteModule\FooPresenter', $factory->formatPresenterClass('Nette:Foo'));
+    }
+
+    public function testMappingWithUnspecifiedModule(): void
+    {
+        $factory = $this->presenterFactory;
+        $factory->setMapping([
+            'Foo2' => 'App2\*Presenter',
+            'Foo3' => 'My\App\*Presenter',
+        ]);
+
+        Assert::same('Foo2Presenter', $factory->formatPresenterClass('Foo2'));
+        Assert::same('App2\BarPresenter', $factory->formatPresenterClass('Foo2:Bar'));
+        Assert::same('App2\BarModule\BazPresenter', $factory->formatPresenterClass('Foo2:Bar:Baz'));
+
+        Assert::same('My\App\BarPresenter', $factory->formatPresenterClass('Foo3:Bar'));
+        Assert::same('My\App\BarModule\BazPresenter', $factory->formatPresenterClass('Foo3:Bar:Baz'));
+    }
+
+    public function testMappingToSubnamespaces(): void
+    {
+        $factory = $this->presenterFactory;
+        $factory->setMapping([
+            '*' => ['App', 'Module\*', 'Presenter\*'],
+        ]);
+        Assert::same('App\Module\Foo\Presenter\Bar', $factory->formatPresenterClass('Foo:Bar'));
+        Assert::same('App\Module\Universe\Module\Foo\Presenter\Bar', $factory->formatPresenterClass('Universe:Foo:Bar'));
+    }
+
+    public function testMappingDirectToNamespace(): void
+    {
+        $factory = $this->presenterFactory;
+        $factory->setMapping([
+            '*' => ['', '*', '*'],
+        ]);
+        Assert::same('Module\Foo\Bar', $factory->formatPresenterClass('Module:Foo:Bar'));
+    }
+
+    public function testInvalidMapping(): void
+    {
+        Assert::exception(
+            function (): void {
+                $factory = $this->presenterFactory;
+                $factory->setMapping([
+                    '*' => ['*', '*'],
+                ]);
+            },
+            \InvalidArgumentException::class,
+            "Invalid mapping mask for module '*'.",
+        );
+    }
+
+}
+
+
+(new PresenterFactoryTest())->run();