Setting the major mode of a new buffer interactively

Question

When creating a new buffer via:

1. C-x b
2. NonExistentBufferName RET RET

I would like Emacs to prompt me for the major mode this buffer is going to use upon opening. Moreover, I want Emacs to infer the major mode in some cases based on the buffer's name:

1. C-x b
2. test.org(no such buffer/file so far) RET RET => org-mode is used without asking me anything.

Could anybody advice on how I can achieve this? Package or, probably, just pure elisp with its hooks and advice?

P.S. I'm using ido if it matters.

Answer 1

I know this is not exactly what you're asking, but the Emacs way to solve this problem is to use C-x C-f instead of C-x b (if you don't want to create a file, just don't use C-x C-s in that buffer).