diff --git a/src/Test/TestCase.php b/src/Test/TestCase.php
new file mode 100644
index 00000000..ed98434c
--- /dev/null
+++ b/src/Test/TestCase.php
@@ -0,0 +1,43 @@
+<?php
+
+namespace ipl\Html\Test;
+
+use DOMDocument;
+use ipl\Html\ValidHtml;
+use PHPUnit\Framework\TestCase as BaseTestCase;
+
+abstract class TestCase extends BaseTestCase
+{
+    /**
+     * Assert that HTML is equal
+     *
+     * @param string    $expected
+     * @param ValidHtml $actual
+     */
+    protected function assertHtml(string $expected, ValidHtml $actual): void
+    {
+        $expectedHtml = str_replace(
+            "\n",
+            '',
+            preg_replace('/^\s+/m', '', trim($expected))
+        );
+        $actualHtml = $actual->render();
+
+        $expectedDom = new DOMDocument();
+        $this->assertTrue($expectedDom->loadHTML($expectedHtml), 'Expected HTML is not valid');
+        $actualDom = new DOMDocument();
+        $this->assertTrue($actualDom->loadHTML($actualHtml), 'Actual HTML is not valid');
+
+        $this->assertEquals($expectedDom, $actualDom);
+    }
+
+    /**
+     * @deprecated Use {@link assertHtml()} instead. assertRendersHtml() suffers from the fact that the HTML being
+     * processed must have a root node, e.g. the HTML `<b>foo</b><b>bar</b>` would always fail with "Extra content at
+     * the end of the document". {@link assertHtml()} just does the job.
+     */
+    protected function assertRendersHtml(string $html, ValidHtml $element): void
+    {
+        $this->assertXmlStringEqualsXmlString($html, $element->render());
+    }
+}
diff --git a/tests/AttributeTest.php b/tests/AttributeTest.php
index 18fc5a4e..aa512ebb 100644
--- a/tests/AttributeTest.php
+++ b/tests/AttributeTest.php
@@ -3,6 +3,7 @@
 namespace ipl\Tests\Html;
 
 use ipl\Html\Attribute;
+use ipl\Html\Test\TestCase;
 
 class AttributeTest extends TestCase
 {
diff --git a/tests/AttributesTest.php b/tests/AttributesTest.php
index 8ce23e8b..82579042 100644
--- a/tests/AttributesTest.php
+++ b/tests/AttributesTest.php
@@ -6,6 +6,7 @@
 use ipl\Html\Attributes;
 use ipl\Html\BaseHtmlElement;
 use ipl\Html\HtmlString;
+use ipl\Html\Test\TestCase;
 use ipl\Html\ValidHtml;
 
 class AttributesTest extends TestCase
diff --git a/tests/BaseHtmlElementTest.php b/tests/BaseHtmlElementTest.php
index cd3b5699..98d3c12a 100644
--- a/tests/BaseHtmlElementTest.php
+++ b/tests/BaseHtmlElementTest.php
@@ -4,6 +4,7 @@
 
 use ipl\Html\BaseHtmlElement;
 use ipl\Html\HtmlString;
+use ipl\Html\Test\TestCase;
 use RuntimeException;
 
 class BaseHtmlElementTest extends TestCase
diff --git a/tests/DeferredTextTest.php b/tests/DeferredTextTest.php
index e926dfe6..1b61539f 100644
--- a/tests/DeferredTextTest.php
+++ b/tests/DeferredTextTest.php
@@ -3,6 +3,7 @@
 namespace ipl\Tests\Html;
 
 use ipl\Html\DeferredText;
+use ipl\Html\Test\TestCase;
 use Exception;
 
 class DeferredTextTest extends TestCase
diff --git a/tests/DocumentationFormsTest.php b/tests/DocumentationFormsTest.php
index 371bbbab..d8048a08 100644
--- a/tests/DocumentationFormsTest.php
+++ b/tests/DocumentationFormsTest.php
@@ -5,6 +5,7 @@
 use ipl\Html\Form;
 use ipl\Html\FormElement\TextElement;
 use ipl\Html\Html;
+use ipl\Html\Test\TestCase;
 
 class DocumentationFormsTest extends TestCase
 {
diff --git a/tests/DocumentationQuickStartTest.php b/tests/DocumentationQuickStartTest.php
index defc275d..5eecf10e 100644
--- a/tests/DocumentationQuickStartTest.php
+++ b/tests/DocumentationQuickStartTest.php
@@ -3,6 +3,7 @@
 namespace ipl\Tests\Html;
 
 use ipl\Html\Html;
+use ipl\Html\Test\TestCase;
 
 class DocumentationQuickStartTest extends TestCase
 {
diff --git a/tests/DocumentationTablesTest.php b/tests/DocumentationTablesTest.php
index 2f955aa8..2ca22903 100644
--- a/tests/DocumentationTablesTest.php
+++ b/tests/DocumentationTablesTest.php
@@ -3,6 +3,7 @@
 namespace ipl\Tests\Html;
 
 use ipl\Html\Table;
+use ipl\Html\Test\TestCase;
 
 class DocumentationTablesTest extends TestCase
 {
diff --git a/tests/FormDecorator/DecorationResultsTest.php b/tests/FormDecorator/DecorationResultsTest.php
index adf3e93a..47632e65 100644
--- a/tests/FormDecorator/DecorationResultsTest.php
+++ b/tests/FormDecorator/DecorationResultsTest.php
@@ -5,7 +5,7 @@
 use ipl\Html\FormDecoration\FormElementDecorationResult;
 use ipl\Html\FormDecoration\Transformation;
 use ipl\Html\Html;
-use ipl\Tests\Html\TestCase;
+use ipl\Html\Test\TestCase;
 
 class DecorationResultsTest extends TestCase
 {
diff --git a/tests/FormDecorator/DecoratorChainTest.php b/tests/FormDecorator/DecoratorChainTest.php
index df885626..af35042d 100644
--- a/tests/FormDecorator/DecoratorChainTest.php
+++ b/tests/FormDecorator/DecoratorChainTest.php
@@ -6,7 +6,7 @@
 use ipl\Html\FormDecoration\DecoratorChain;
 use ipl\Html\Contract\FormElementDecoration;
 use ipl\Html\HtmlDocument;
-use ipl\Tests\Html\TestCase;
+use ipl\Html\Test\TestCase;
 use ValueError;
 
 class DecoratorChainTest extends TestCase
diff --git a/tests/FormDecorator/DescriptionDecoratorTest.php b/tests/FormDecorator/DescriptionDecoratorTest.php
index 6e4146cf..60efd59a 100644
--- a/tests/FormDecorator/DescriptionDecoratorTest.php
+++ b/tests/FormDecorator/DescriptionDecoratorTest.php
@@ -7,7 +7,7 @@
 use ipl\Html\FormDecoration\DescriptionDecorator;
 use ipl\Html\FormElement\FieldsetElement;
 use ipl\Html\FormElement\TextElement;
-use ipl\Tests\Html\TestCase;
+use ipl\Html\Test\TestCase;
 
 class DescriptionDecoratorTest extends TestCase
 {
diff --git a/tests/FormDecorator/ErrorsDecoratorTest.php b/tests/FormDecorator/ErrorsDecoratorTest.php
index 9888a4d2..a4abce14 100644
--- a/tests/FormDecorator/ErrorsDecoratorTest.php
+++ b/tests/FormDecorator/ErrorsDecoratorTest.php
@@ -6,7 +6,7 @@
 use ipl\Html\FormDecoration\FormElementDecorationResult;
 use ipl\Html\FormDecoration\ErrorsDecorator;
 use ipl\Html\FormElement\TextElement;
-use ipl\Tests\Html\TestCase;
+use ipl\Html\Test\TestCase;
 
 class ErrorsDecoratorTest extends TestCase
 {
diff --git a/tests/FormDecorator/FieldsetDecoratorTest.php b/tests/FormDecorator/FieldsetDecoratorTest.php
index b83388e4..a6ccce84 100644
--- a/tests/FormDecorator/FieldsetDecoratorTest.php
+++ b/tests/FormDecorator/FieldsetDecoratorTest.php
@@ -7,7 +7,7 @@
 use ipl\Html\FormDecoration\FieldsetDecorator;
 use ipl\Html\FormElement\FieldsetElement;
 use ipl\Html\FormElement\TextElement;
-use ipl\Tests\Html\TestCase;
+use ipl\Html\Test\TestCase;
 
 class FieldsetDecoratorTest extends TestCase
 {
diff --git a/tests/FormDecorator/FormDecorationResultTest.php b/tests/FormDecorator/FormDecorationResultTest.php
index ae4f0d42..d82db75a 100644
--- a/tests/FormDecorator/FormDecorationResultTest.php
+++ b/tests/FormDecorator/FormDecorationResultTest.php
@@ -5,7 +5,7 @@
 use ipl\Html\Form;
 use ipl\Html\FormDecoration\FormDecorationResult;
 use ipl\Html\Html;
-use ipl\Tests\Html\TestCase;
+use ipl\Html\Test\TestCase;
 
 class FormDecorationResultTest extends TestCase
 {
diff --git a/tests/FormDecorator/FormDecorationTest.php b/tests/FormDecorator/FormDecorationTest.php
index 5f1f2f1e..05daaa8c 100644
--- a/tests/FormDecorator/FormDecorationTest.php
+++ b/tests/FormDecorator/FormDecorationTest.php
@@ -9,7 +9,7 @@
 use ipl\Html\Contract\FormElementDecoration;
 use ipl\Html\FormDecoration\Transformation;
 use ipl\Html\Html;
-use ipl\Tests\Html\TestCase;
+use ipl\Html\Test\TestCase;
 
 class FormDecorationTest extends TestCase
 {
diff --git a/tests/FormDecorator/FormElementDecorationTest.php b/tests/FormDecorator/FormElementDecorationTest.php
index 49480ed1..a45a560d 100644
--- a/tests/FormDecorator/FormElementDecorationTest.php
+++ b/tests/FormDecorator/FormElementDecorationTest.php
@@ -4,7 +4,7 @@
 
 use ipl\Html\Form;
 use ipl\Html\FormElement\TextElement;
-use ipl\Tests\Html\TestCase;
+use ipl\Html\Test\TestCase;
 use ipl\Tests\Html\TestDummy\SimpleFormElementDecorator;
 use RuntimeException;
 
diff --git a/tests/FormDecorator/HtmlTagDecoratorTest.php b/tests/FormDecorator/HtmlTagDecoratorTest.php
index c896d9f7..e5656116 100644
--- a/tests/FormDecorator/HtmlTagDecoratorTest.php
+++ b/tests/FormDecorator/HtmlTagDecoratorTest.php
@@ -8,7 +8,7 @@
 use ipl\Html\FormDecoration\HtmlTagDecorator;
 use ipl\Html\FormDecoration\Transformation;
 use ipl\Html\FormElement\TextElement;
-use ipl\Tests\Html\TestCase;
+use ipl\Html\Test\TestCase;
 use RuntimeException;
 
 class HtmlTagDecoratorTest extends TestCase
diff --git a/tests/FormDecorator/LabelDecoratorTest.php b/tests/FormDecorator/LabelDecoratorTest.php
index cae1e03f..5927ff45 100644
--- a/tests/FormDecorator/LabelDecoratorTest.php
+++ b/tests/FormDecorator/LabelDecoratorTest.php
@@ -9,7 +9,7 @@
 use ipl\Html\FormElement\SubmitButtonElement;
 use ipl\Html\FormElement\SubmitElement;
 use ipl\Html\FormElement\TextElement;
-use ipl\Tests\Html\TestCase;
+use ipl\Html\Test\TestCase;
 
 class LabelDecoratorTest extends TestCase
 {
diff --git a/tests/FormElement/CheckboxElementTest.php b/tests/FormElement/CheckboxElementTest.php
index 1a78f423..c14a5f5e 100644
--- a/tests/FormElement/CheckboxElementTest.php
+++ b/tests/FormElement/CheckboxElementTest.php
@@ -3,6 +3,7 @@
 namespace ipl\Tests\Html;
 
 use ipl\Html\FormElement\CheckboxElement;
+use ipl\Html\Test\TestCase;
 use ipl\I18n\NoopTranslator;
 use ipl\I18n\StaticTranslator;
 
diff --git a/tests/FormElement/FieldsetElementTest.php b/tests/FormElement/FieldsetElementTest.php
index 1b33c155..7a3567ea 100644
--- a/tests/FormElement/FieldsetElementTest.php
+++ b/tests/FormElement/FieldsetElementTest.php
@@ -7,7 +7,7 @@
 use ipl\Html\FormElement\FieldsetElement;
 use ipl\I18n\NoopTranslator;
 use ipl\I18n\StaticTranslator;
-use ipl\Tests\Html\TestCase;
+use ipl\Html\Test\TestCase;
 use ipl\Tests\Html\TestDummy\SimpleFormElementDecorator;
 use ipl\Validator\CallbackValidator;
 use LogicException;
diff --git a/tests/FormElement/FileElementTest.php b/tests/FormElement/FileElementTest.php
index 4be80eeb..8936959b 100644
--- a/tests/FormElement/FileElementTest.php
+++ b/tests/FormElement/FileElementTest.php
@@ -11,7 +11,7 @@
 use ipl\I18n\NoopTranslator;
 use ipl\I18n\StaticTranslator;
 use ipl\Tests\Html\Lib\FileElementWithAdjustableConfig;
-use ipl\Tests\Html\TestCase;
+use ipl\Html\Test\TestCase;
 use Psr\Http\Message\StreamInterface;
 
 class FileElementTest extends TestCase
diff --git a/tests/FormElement/FormElementValidationTest.php b/tests/FormElement/FormElementValidationTest.php
index 01fdfd24..f6b48b20 100644
--- a/tests/FormElement/FormElementValidationTest.php
+++ b/tests/FormElement/FormElementValidationTest.php
@@ -7,7 +7,7 @@
 use ipl\Html\FormElement\TextElement;
 use ipl\I18n\NoopTranslator;
 use ipl\I18n\StaticTranslator;
-use ipl\Tests\Html\TestCase;
+use ipl\Html\Test\TestCase;
 use ipl\Validator\CallbackValidator;
 
 class FormElementValidationTest extends TestCase
diff --git a/tests/FormElement/LocalDateTimeElementTest.php b/tests/FormElement/LocalDateTimeElementTest.php
index cc947544..d1aa5182 100644
--- a/tests/FormElement/LocalDateTimeElementTest.php
+++ b/tests/FormElement/LocalDateTimeElementTest.php
@@ -4,6 +4,7 @@
 
 use DateTime;
 use ipl\Html\FormElement\LocalDateTimeElement;
+use ipl\Html\Test\TestCase;
 
 class LocalDateTimeElementTest extends TestCase
 {
diff --git a/tests/FormElement/RadioElementTest.php b/tests/FormElement/RadioElementTest.php
index 5d5c90dc..8c3a5cf5 100644
--- a/tests/FormElement/RadioElementTest.php
+++ b/tests/FormElement/RadioElementTest.php
@@ -9,7 +9,7 @@
 use ipl\Html\FormElement\RadioOption;
 use ipl\I18n\NoopTranslator;
 use ipl\I18n\StaticTranslator;
-use ipl\Tests\Html\TestCase;
+use ipl\Html\Test\TestCase;
 
 class RadioElementTest extends TestCase
 {
diff --git a/tests/FormElement/SelectElementTest.php b/tests/FormElement/SelectElementTest.php
index cf44581f..254c917d 100644
--- a/tests/FormElement/SelectElementTest.php
+++ b/tests/FormElement/SelectElementTest.php
@@ -7,7 +7,7 @@
 use ipl\Html\FormElement\SelectOption;
 use ipl\I18n\NoopTranslator;
 use ipl\I18n\StaticTranslator;
-use ipl\Tests\Html\TestCase;
+use ipl\Html\Test\TestCase;
 use UnexpectedValueException;
 
 class SelectElementTest extends TestCase
diff --git a/tests/FormElement/SelectOptionTest.php b/tests/FormElement/SelectOptionTest.php
index 0ad3fcf4..832b4a38 100644
--- a/tests/FormElement/SelectOptionTest.php
+++ b/tests/FormElement/SelectOptionTest.php
@@ -4,7 +4,7 @@
 
 use ipl\Html\FormElement\SelectElement;
 use ipl\Html\FormElement\SelectOption;
-use ipl\Tests\Html\TestCase;
+use ipl\Html\Test\TestCase;
 
 class SelectOptionTest extends TestCase
 {
diff --git a/tests/FormElement/SubmitButtonElementTest.php b/tests/FormElement/SubmitButtonElementTest.php
index 421c8477..c7a25ca7 100644
--- a/tests/FormElement/SubmitButtonElementTest.php
+++ b/tests/FormElement/SubmitButtonElementTest.php
@@ -4,7 +4,7 @@
 
 use ipl\Html\Form;
 use ipl\Html\FormElement\SubmitButtonElement;
-use ipl\Tests\Html\TestCase;
+use ipl\Html\Test\TestCase;
 
 class SubmitButtonElementTest extends TestCase
 {
diff --git a/tests/FormElement/TextElementTest.php b/tests/FormElement/TextElementTest.php
index 026d7f8b..284da392 100644
--- a/tests/FormElement/TextElementTest.php
+++ b/tests/FormElement/TextElementTest.php
@@ -4,7 +4,7 @@
 
 use ipl\Html\Attributes;
 use ipl\Html\FormElement\TextElement;
-use ipl\Tests\Html\TestCase;
+use ipl\Html\Test\TestCase;
 
 class TextElementTest extends TestCase
 {
diff --git a/tests/FormElementDecoratorTest.php b/tests/FormElementDecoratorTest.php
index 02f37a17..9b3b3c82 100644
--- a/tests/FormElementDecoratorTest.php
+++ b/tests/FormElementDecoratorTest.php
@@ -3,6 +3,7 @@
 namespace ipl\Tests\Html;
 
 use ipl\Html\Form;
+use ipl\Html\Test\TestCase;
 use ipl\Tests\Html\TestDummy\PositionedFormElementDecorator;
 use ipl\Tests\Html\TestDummy\SimpleFormElementDecorator;
 use ipl\Tests\Html\TestDummy\WithinContainerFormElementDecorator;
diff --git a/tests/FormElementsTest.php b/tests/FormElementsTest.php
index 4c02f30e..7305f099 100644
--- a/tests/FormElementsTest.php
+++ b/tests/FormElementsTest.php
@@ -4,6 +4,7 @@
 
 use ipl\Html\Form;
 use ipl\Html\FormElement\FormElements;
+use ipl\Html\Test\TestCase;
 
 class FormElementsTest extends TestCase
 {
diff --git a/tests/FormTest.php b/tests/FormTest.php
index a7794832..117d9b6c 100644
--- a/tests/FormTest.php
+++ b/tests/FormTest.php
@@ -4,6 +4,7 @@
 
 use ipl\Html\Form;
 use ipl\Html\FormElement\BaseFormElement;
+use ipl\Html\Test\TestCase;
 use Psr\Http\Message\ServerRequestInterface;
 
 class FormTest extends TestCase
diff --git a/tests/FormattedStringTest.php b/tests/FormattedStringTest.php
index fcef4c77..efb6c0dd 100644
--- a/tests/FormattedStringTest.php
+++ b/tests/FormattedStringTest.php
@@ -4,6 +4,7 @@
 
 use ipl\Html\FormattedString;
 use ipl\Html\Html;
+use ipl\Html\Test\TestCase;
 use ipl\Tests\Html\TestDummy\ObjectThatCanBeCastedToString;
 
 class FormattedStringTest extends TestCase
diff --git a/tests/HtmlDocumentTest.php b/tests/HtmlDocumentTest.php
index c11679de..5af448b1 100644
--- a/tests/HtmlDocumentTest.php
+++ b/tests/HtmlDocumentTest.php
@@ -5,6 +5,7 @@
 use ipl\Html\BaseHtmlElement;
 use ipl\Html\Html as h;
 use ipl\Html\HtmlDocument;
+use ipl\Html\Test\TestCase;
 use ipl\Tests\Html\TestDummy\AddsContentDuringAssemble;
 use ipl\Tests\Html\TestDummy\AddsWrapperDuringAssemble;
 use ipl\Tests\Html\TestDummy\IterableElement;
diff --git a/tests/HtmlStringTest.php b/tests/HtmlStringTest.php
index ab543cbe..88d0236c 100644
--- a/tests/HtmlStringTest.php
+++ b/tests/HtmlStringTest.php
@@ -3,6 +3,7 @@
 namespace ipl\Tests\Html;
 
 use ipl\Html\HtmlString;
+use ipl\Html\Test\TestCase;
 use ipl\Html\Text;
 
 class HtmlStringTest extends TestCase
diff --git a/tests/HtmlTest.php b/tests/HtmlTest.php
index 426afb53..f870ee14 100644
--- a/tests/HtmlTest.php
+++ b/tests/HtmlTest.php
@@ -4,6 +4,7 @@
 
 use InvalidArgumentException;
 use ipl\Html\Html;
+use ipl\Html\Test\TestCase;
 
 class HtmlTest extends TestCase
 {
diff --git a/tests/TemplateStringTest.php b/tests/TemplateStringTest.php
index 0bf0d117..f6f0a4ab 100644
--- a/tests/TemplateStringTest.php
+++ b/tests/TemplateStringTest.php
@@ -3,8 +3,9 @@
 namespace ipl\Tests\Html;
 
 use Exception;
-use ipl\Html\TemplateString;
 use ipl\Html\Html;
+use ipl\Html\TemplateString;
+use ipl\Html\Test\TestCase;
 
 class TemplateStringTest extends TestCase
 {
diff --git a/tests/TestCase.php b/tests/TestCase.php
deleted file mode 100644
index 22dfe954..00000000
--- a/tests/TestCase.php
+++ /dev/null
@@ -1,49 +0,0 @@
-<?php
-
-namespace ipl\Tests\Html;
-
-use DOMDocument;
-use ipl\Html\ValidHtml;
-
-// phpcs:disable
-if (class_exists('PHPUnit_Util_XML')) {
-    // Support older PHPUnit versions
-    class_alias('PHPUnit_Util_XML', 'PHPUnit\\Util\\Xml');
-}
-
-// phpcs:enable
-
-abstract class TestCase extends \PHPUnit\Framework\TestCase
-{
-    /**
-     * Assert that HTML is equal
-     *
-     * @param string    $expectedHtml
-     * @param ValidHtml $actual
-     */
-    protected function assertHtml($expectedHtml, ValidHtml $actualHtml)
-    {
-        $expectedHtml = str_replace(
-            "\n",
-            '',
-            preg_replace('/^\s+/m', '', trim($expectedHtml))
-        );
-
-        $expected = new DOMDocument();
-        $this->assertTrue($expected->loadHTML($expectedHtml), 'Expected HTML is not valid');
-        $actual = new DOMDocument();
-        $this->assertTrue($actual->loadHTML($actualHtml->render()), 'Actual HTML is not valid');
-
-        $this->assertEquals($expected, $actual);
-    }
-
-    /**
-     * @deprecated Use {@link assertHtml()} instead. assertRendersHtml() suffers from the fact that the HTML being
-     * processed must have a root node, e.g. the HTML `<b>foo</b><b>bar</b>` would always fail with "Extra content at
-     * the end of the document". {@link assertHtml()} just does the job.
-     */
-    protected function assertRendersHtml($html, ValidHtml $element)
-    {
-        $this->assertXmlStringEqualsXmlString($html, $element->render());
-    }
-}