Automigrate fail: Index primary is non-iteratable

[Dmitry]

Can't migrate space with it's modified declaration:

 box.spacer.automigrate = true
 box.spacer:space(space_declaration)

In moonwalker.lua, inside moonwalker(opts):

	local index      = opts.index or space.index[0]
	local keyfields  = create_keyfields(index)
	if index.type ~= "TREE" then
		error("Index "..index.name.." in space "..space.name.." is non-iteratable",2)
	end

But my space has "HASH" primary index, not "TREE".
So I get an error "Index primary in space <my_space_name> is non-iteratable"