merlin outline fails to find type information in *.mli files

[taquangtrung]

Hi,

I encountered a problem when implementing the Emacs module merlin-imenu.el (#1013) that the command outline of merlin cannot get correct type information in*.mli modules.

For example, here is a code segment of module ~/.opam/4.08.1/lib/llvm/llvm.mli, line 1976:

(** [insertion_block b] returns the basic block that the builder [b] is
    positioned to insert into. Raises [Not_Found] if the instruction builder is
    uninitialized.
    See the method [llvm::LLVMBuilder::GetInsertBlock]. *)
val insertion_block : llbuilder -> llbasicblock

Here is the item related to the function insertion_block that merlin outline returns:

((assoc) (start (assoc) (line . 1980) (col . 0)) (end (assoc) (line . 1980) (col . 47)) (name . insertion_block) (kind . Value) (type . null) (children))

As can be seen above, the type information obtained for insertion_block is null.

Could you please check if this is a bug?

(Currenlty, I have to use the command type-enclosing to get the type information in *.mli modules, but it is very slow.)