diff --git a/tests/SPC/util/DependencyUtilTest.php b/tests/SPC/util/DependencyUtilTest.php
new file mode 100644
index 00000000..b77d9d79
--- /dev/null
+++ b/tests/SPC/util/DependencyUtilTest.php
@@ -0,0 +1,90 @@
+<?php
+
+declare(strict_types=1);
+
+namespace SPC\Tests\util;
+
+use PHPUnit\Framework\TestCase;
+use SPC\exception\WrongUsageException;
+use SPC\store\Config;
+use SPC\util\DependencyUtil;
+
+/**
+ * @internal
+ */
+final class DependencyUtilTest extends TestCase
+{
+    public function testGetExtLibsByDeps(): void
+    {
+        // example
+        Config::$source = [
+            'test1' => [
+                'type' => 'url',
+                'url' => 'https://pecl.php.net/get/APCu',
+                'filename' => 'apcu.tgz',
+                'license' => [
+                    'type' => 'file',
+                    'path' => 'LICENSE',
+                ],
+            ],
+        ];
+        Config::$lib = [
+            'libaaa' => [
+                'source' => 'test1',
+                'static-libs' => ['libaaa.a'],
+                'lib-depends' => ['libbbb', 'libccc'],
+                'lib-suggests' => ['libeee'],
+            ],
+            'libbbb' => [
+                'source' => 'test1',
+                'static-libs' => ['libbbb.a'],
+                'lib-suggests' => ['libccc'],
+            ],
+            'libccc' => [
+                'source' => 'test1',
+                'static-libs' => ['libccc.a'],
+            ],
+            'libeee' => [
+                'source' => 'test1',
+                'static-libs' => ['libeee.a'],
+                'lib-suggests' => ['libfff'],
+            ],
+            'libfff' => [
+                'source' => 'test1',
+                'static-libs' => ['libfff.a'],
+            ],
+        ];
+        Config::$ext = [
+            'ext-a' => [
+                'type' => 'builtin',
+                'lib-depends' => ['libaaa'],
+                'ext-suggests' => ['ext-b'],
+            ],
+            'ext-b' => [
+                'type' => 'builtin',
+                'lib-depends' => ['libeee'],
+            ],
+        ];
+        // test getExtLibsByDeps (notmal test with ext-depends and lib-depends)
+
+        [$exts, $libs, $not_included] = DependencyUtil::getExtsAndLibs(['ext-a'], include_suggested_exts: true);
+        $this->assertContains('libbbb', $libs);
+        $this->assertContains('libccc', $libs);
+        $this->assertContains('ext-b', $exts);
+        $this->assertContains('ext-b', $not_included);
+        // test dep order
+        $this->assertIsInt($b = array_search('libbbb', $libs));
+        $this->assertIsInt($c = array_search('libccc', $libs));
+        $this->assertIsInt($a = array_search('libaaa', $libs));
+        // libbbb, libaaa
+        $this->assertTrue($b < $a);
+        $this->assertTrue($c < $a);
+        $this->assertTrue($c < $b);
+    }
+
+    public function testNotExistExtException(): void
+    {
+        $this->expectException(WrongUsageException::class);
+        DependencyUtil::getExtsAndLibs(['sdsd']);
+    }
+}