Fix error messages in DataLayouts (#2275)

Author: charleskawczynski

src/DataLayouts/DataLayouts.jl

@@ -364,9 +364,9 @@ end
 
 @noinline _property_view(
     data::AbstractData{S},
-    ::Val{Nothing},
+    ::Val{nothing},
     name,
-) where {S} = error("Invalid field name $name for type $(S)")
+) where {S} = error("Invalid field name `$name` for type `$(S)`.")
 
 # In the past, we've sometimes needed a generated function
 # for inference and constant propagation:

test/DataLayouts/data0d.jl

@@ -1,5 +1,5 @@
 #=
-julia --project=test
+julia --project
 using Revise; include(joinpath("test", "DataLayouts", "data0d.jl"))
 =#
 using Test
@@ -65,6 +65,14 @@ end
     @test_throws MethodError data[] = SB
 end
 
+@testset "DataF error messages" begin
+    SA = (; a = 1.0)
+    data = DataF{typeof(SA)}(ArrayType{Float64})
+    @test_throws ErrorException(
+        "Invalid field name `oops` for type `$(typeof(SA))`.",
+    ) data.oops
+end
+
 @testset "DataF broadcasting between 0D data objects and scalars" begin
     for FT in TestFloatTypes
         S = Complex{FT}