Fix bug in field2array

Author: dennisYatunin

src/Fields/Fields.jl

@@ -614,7 +614,7 @@ function field2array(field::Field)
                represented by $f_axis_size array elements (must be 1)")
     end
     axes(field) isa Spaces.AbstractSpectralElementSpace && return vec(parent(field))
-    return reshape(parent(field), nlevels(axes(field)), :)
+    return reshape(parent(field), DataLayouts.nlevels(field_values(field)), :)
 end
 
 set_mask!(space::Spaces.AbstractSpace, field::Field) =

src/Fields/broadcast.jl

@@ -167,10 +167,13 @@ Base.similar(
     return dest
 end
 
-# Fused multi-broadcast entry point for Fields
+# Fused multi-broadcast entry point for Fields. The mask argument must be
+# constrained to DataMask because an unconstrained second argument makes this
+# ambiguous with copyto! methods that only constrain their second arguments,
+# like the ones for Lmul and Rmul in ArrayLayouts.
 function Base.copyto!(
     fmbc::FusedMultiBroadcast{T},
-    mask = get_mask(axes(first(fmbc.pairs).first)),
+    mask::DataLayouts.DataMask = get_mask(axes(first(fmbc.pairs).first)),
 ) where {N, T <: NTuple{N, Pair{<:Field, <:Any}}}
     fmb_data = FusedMultiBroadcast(
         map(fmbc.pairs) do pair