`scatter!` fails for `Vector{Union{missing, Float64}}`

[debsankha]

what version of Makie are you running? (]st -m Makie)

• Makie v0.23.0

can you reproduce the bug with a fresh environment ? (]activate --temp; add Makie)

• Yes.

What platform + GPU are you on?

• Ubuntu 24.04, AMD/ATI Phoenix1

Which backend are you using?

• GLMakie

Please provide an minimal example of the failing code.

using GLMakie

x = [1.0, 2, 3, 4, 5]
y = [1.0, 2, missing, 4, 5]

x2 = [12, 13, missing, 14, 15.0]
y2 = [22, 23, missing, 24, 25.0]

fig = Figure(; size=(800, 800))
axis = Axis(fig[1, 1]; aspect=1, xlabel="X", ylabel="Y")

scatter!(axis, x, y; alpha=0.5)
scatter!(axis, x2, y2; alpha=0.5)

Produces error:

ERROR: LoadError: MethodError: no method matching create_dim_conversion(::Type{Union{Missing, Float64}})
The function `create_dim_conversion` exists, but no method is defined for this combination of argument types.

Closest candidates are:
  create_dim_conversion(::Type{Categorical})
   @ Makie ~/.julia/environments/v1.11/dev/Makie/src/dim-converts/categorical-integration.jl:48
  create_dim_conversion(::Type{<:Dates.AbstractTime})
   @ Makie ~/.julia/environments/v1.11/dev/Makie/src/dim-converts/dates-integration.jl:59
  create_dim_conversion(::Type{<:Enum})
   @ Makie ~/.julia/environments/v1.11/dev/Makie/src/dim-converts/categorical-integration.jl:53
  ...

Stacktrace:
  [1] dim_conversion_from_args(values::Vector{Union{Missing, Float64}})
    @ Makie ~/.julia/environments/v1.11/dev/Makie/src/dim-converts/dim-converts.jl:114
  [2] convert_dim_observable(conversions::Makie.DimConversions, dim::Int64, value::Observable{Any}, deregister::Vector{Observables.ObserverFunction})
    @ Makie ~/.julia/environments/v1.11/dev/Makie/src/dim-converts/dim-converts.jl:200
  [3] (::Makie.var"#220#222"{UnionAll, PointBased, Tuple{Observable{Any}, Observable{Any}}, Vector{Observables.ObserverFunction}, Makie.DimConversions})(i::Int6
4)
    @ Makie ~/.julia/environments/v1.11/dev/Makie/src/dim-converts/dim-converts.jl:189
    @ Makie ~/.julia/environments/v1.11/dev/Makie/src/dim-converts/dim-converts.jl:189
  [4] ntuple
    @ ./ntuple.jl:19 [inlined]
  [5] try_dim_convert(P::Type{Scatter}, PTrait::PointBased, user_attributes::Dict{Symbol, Any}, args_obs::Tuple{Observable{Any}, Observable{Any}}, deregister::Vector{Observables.ObserverFunction})
    @ Makie ~/.julia/environments/v1.11/dev/Makie/src/dim-converts/dim-converts.jl:183
  [6] conversion_pipeline(P::Type{Scatter}, used_attrs::Tuple{}, args::Tuple{Vector{Union{Missing, Float64}}, Vector{Union{Missing, Float64}}}, kw_obs::Observable{Vector{Pair{Symbol, Any}}}, args_obs::Tuple{Observable{Any}, Observable{Any}}, user_attributes::Dict{Symbol, Any}, deregister::Vector{Observables.ObserverFunction}, recursion::Int64)
    @ Makie ~/.julia/environments/v1.11/dev/Makie/src/interfaces.jl:220
  [7] conversion_pipeline(P::Type{Scatter}, used_attrs::Tuple{}, args::Tuple{Vector{Union{Missing, Float64}}, Vector{Union{Missing, Float64}}}, kw_obs::Observable{Vector{Pair{Symbol, Any}}}, args_obs::Tuple{Observable{Any}, Observable{Any}}, user_attributes::Dict{Symbol, Any}, deregister::Vector{Observables.ObserverFunction})
    @ Makie ~/.julia/environments/v1.11/dev/Makie/src/interfaces.jl:213
  [8] (Scatter)(user_args::Tuple{Vector{Union{Missing, Float64}}, Vector{Union{Missing, Float64}}}, user_attributes::Dict{Symbol, Any})
    @ Makie ~/.julia/environments/v1.11/dev/Makie/src/interfaces.jl:273
  [9] _create_plot!(::Function, ::Dict{Symbol, Any}, ::Axis, ::Vector{Union{Missing, Float64}}, ::Vararg{Vector{Union{Missing, Float64}}})
    @ Makie ~/.julia/environments/v1.11/dev/Makie/src/figureplotting.jl:377
 [10] scatter!(::Axis, ::Vararg{Any}; kw::@Kwargs{alpha::Float64})
    @ MakieCore ~/.julia/environments/v1.11/dev/Makie/MakieCore/src/recipes.jl:512

[debsankha]

In the calling side, adding the following fixes the issue:

import Makie: create_dim_conversion

create_dim_conversion(union_typ::Type{Union{Missing,T}}) where {T<:Real} =
    create_dim_conversion(union_typ.b)

[t-bltg]

You can open a PR I guess ?
Adding a test would be appreciated too !

[ryofurue]

I was about to submit a bug report when I found this report. My program has stopped working for the same error, in my case, with contourf!. As an emergency fix, I've included the above patch code and now my program has started to work again.