In hypothetical scenario where india decides to extend its border nepal and srilanka will be first choice ..bangladesh will be last one ..if bangladesh becomes an enemy state in futre india will play different game which most of us know rather than making itself dirty
No, That would be only if Nepal and Sri Lanka themselves chose to do so. India will not and should not try anything of that sort. only if the respective states feel they have economic gains, they ll choose to join Indian Union.