Add TestCase.

For now, this just tests that all the unit values are parsed.
(Other tests can be added here, but are beyond the scope of this change.)

Author: JakeQZ

tests/Value/SizeTest.php

@@ -0,0 +1,51 @@
+<?php
+
+namespace Sabberworm\CSS\Tests\Value;
+
+use PHPUnit\Framework\TestCase;
+use Sabberworm\CSS\Parsing\ParserState;
+use Sabberworm\CSS\Settings;
+use Sabberworm\CSS\Value\Size;
+
+/**
+ * @covers Size
+ */
+final class SizeTest extends TestCase
+{
+    /**
+     * @return array<string, array{0: string}>
+     */
+    public static function provideUnit(): array
+    {
+        $units = [
+            'px', 'pt', 'pc',
+            'cm', 'mm', 'mozmm', 'in',
+            'vh', 'dvh', 'svh', 'lvh',
+            'vw', 'vmin', 'vmax', 'rem',
+            '%', 'em', 'ex', 'ch', 'fr',
+            'deg', 'grad', 'rad', 's', 'ms', 'turn', 'Hz', 'kHz',
+        ];
+
+        return \array_combine(
+            $units,
+            \array_map(
+                function(string $unit): array {
+                    return [$unit];
+                },
+                $units
+            )
+        );
+    }
+
+    /**
+     * @test
+     *
+     * @dataProvider provideUnit
+     */
+    public function parsesUnit(string $unit)
+    {
+        $subject = Size::parse(new ParserState('1' . $unit, Settings::create()));
+
+        self::assertSame($unit, $subject->getUnit());
+    }
+}