Get rid of mockery library. Still have some troubles with functional tests for api

common/tests/helpers/ExtendedPHPMock.php

@@ -0,0 +1,28 @@
+<?php
+declare(strict_types=1);
+
+namespace common\tests\helpers;
+
+use phpmock\phpunit\PHPMock;
+use PHPUnit\Framework\MockObject\MockObject;
+use ReflectionClass;
+
+trait ExtendedPHPMock {
+    use PHPMock {
+        getFunctionMock as private getOriginalFunctionMock;
+        defineFunctionMock as private defineOriginalFunctionMock;
+    }
+
+    public function getFunctionMock($namespace, $name): MockObject {
+        return $this->getOriginalFunctionMock(static::getClassNamespace($namespace), $name);
+    }
+
+    public static function defineFunctionMock($namespace, $name) {
+        static::defineOriginalFunctionMock(static::getClassNamespace($namespace), $name);
+    }
+
+    private static function getClassNamespace(string $className): string {
+        return (new ReflectionClass($className))->getNamespaceName();
+    }
+
+}