moduleListMock = $this->createMock(ModuleListInterface::class); $this->objectManager = new ObjectManager($this); $this->moduleService = $this->objectManager->getObject( ModuleService::class, [ 'moduleList' => $this->moduleListMock, ] ); } /** * Test getModules method * * @return void */ public function testGetModules() { $moduleNames = ['Magento_Backend', 'Magento_Catalog', 'Magento_Customer']; $this->moduleListMock->expects($this->once())->method('getNames')->willReturn($moduleNames); $expected = $moduleNames; $actual = $this->moduleService->getModules(); $this->assertEquals($expected, $actual); } }