Leo Liu <sdl.web@gmail.com> writes:

> Treating things between parentheses as sexp [...] is not lisp-specific

This part makes sense to me.

> using indent-sexp to indent it is not lisp-specific

This is what surprises me.  How does
lisp-indent-calc-next/calculate-lisp-indent give correct results for
non-lisp?  I think using prog-indent-sexp for non-lisp would make more
sense.

Anyway, the following patch seems to work with your examples.