Hi,
We had have the same problem with syntax check for SAPUI5 and We have solved by working with TypeScript and Visual Studio (but it is posible with eclipse too).
Please check our blog to find the way how We did it.
http://newuibcn.com/es/2015/02/programando-aplicaciones-usando-sapui5-typescript/Hi,
The blog is in spanish but google translate maybe can help you.
Best regards,
Víctor