dict_list changes Dict type #327
Description
A dict of type, say, {Symbol, Any} such as Dict{Symbol, Any}(:a => collect(1:10), :b => true) will be turned into a Vector{Dict{Symbol, Integer}}. This can create unwanted behavior.
I propose the following modification to _dict_list:
function _dict_list(c::AbstractDict)
dict = typeof(c)
iterable_fields = filter(k -> typeof(c[k]) <: Vector, keys(c))
non_iterables = setdiff(keys(c), iterable_fields)
iterable_dict = dict(iterable_fields .=> getindex.(Ref(c), iterable_fields))
non_iterable_dict = dict(non_iterables .=> getindex.(Ref(c), non_iterables))
vec(
map(Iterators.product(values(iterable_dict)...)) do vals
dd = [k=>convert(eltype(c[k]),v) for (k,v) in zip(keys(iterable_dict),vals)]
if isempty(non_iterable_dict)
Dict(dd)
elseif isempty(iterable_dict)
non_iterable_dict
else
# We can't use merge here because it promotes types.
# The uniqueness of the dictionary keys is guaranteed.
dict(dd..., collect(non_iterable_dict)...)
end
end
)
end