[compat] use ColorTypes.nan for HSV types

Author: johnnychen94

src/compat.jl

@@ -6,8 +6,13 @@
     @inline isnothing(x) = x === nothing
 end
 
-# FIXME: upstream https://github.com/JuliaGraphics/ColorVectorSpace.jl/issues/75
-@inline _nan(::Type{HSV{Float16}}) = HSV{Float16}(NaN16,NaN16,NaN16)
-@inline _nan(::Type{HSV{Float32}}) = HSV{Float32}(NaN32,NaN32,NaN32)
-@inline _nan(::Type{HSV{Float64}}) = HSV{Float64}(NaN,NaN,NaN)
-@inline _nan(::Type{T}) where {T} = nan(T)
+if hasmethod(nan, Tuple{Type{HSV{Float32},}})
+    # requires ColorTypes v0.11 and ColorVectorSpace v0.9.4
+    # https://github.com/JuliaGraphics/ColorVectorSpace.jl/issues/75
+    @inline _nan(::Type{T}) where T = nan(T)
+else
+    @inline _nan(::Type{HSV{Float16}}) = HSV{Float16}(NaN16,NaN16,NaN16)
+    @inline _nan(::Type{HSV{Float32}}) = HSV{Float32}(NaN32,NaN32,NaN32)
+    @inline _nan(::Type{HSV{Float64}}) = HSV{Float64}(NaN,NaN,NaN)
+    @inline _nan(::Type{T}) where {T} = nan(T)
+end