baoshi-was/app/Traits/TestMockSubServices.php

<?php
namespace App\Traits;

trait TestMockSubServices{
    function subMock(array $serviceDefinition){
        $mockingService=$this->createPartialMock(
            $serviceDefinition['class'],
            array_keys($serviceDefinition['methods'])
        );
        foreach ($serviceDefinition['methods'] as $mName=>$mVal){
            $mockingService->method($mName)->willReturn($mVal);
        }

        foreach ($serviceDefinition['subServices'] as $subService){
            $mockingService->instant(
                $subService['serviceName'],
                ($subServiceMock=function()use($subService){
                    $subServiceMock=$this->createPartialMock(
                        $subService['class'],
                        array_keys($subService['methods'])
                    );
                    foreach ($subService['methods'] as $methodName=>$methodVal){
                        $subServiceMock->method($methodName)->willReturn($methodVal);
                    }
                    return $subServiceMock;
                })()
            );
        }
        return $mockingService;
    }

}