Small refactor

Author: mtfishman

src/abstractblocksparsearray/wrappedabstractblocksparsearray.jl

@@ -344,11 +344,9 @@ function Base.Array(a::AnyAbstractBlockSparseArray)
 end
 
 function SparseArraysBase.isstored(
-  a::AnyAbstractBlockSparseArray{<:Any,N}, I::Vararg{Int,N}
-) where {N}
-  bI = BlockIndex(findblockindex.(axes(a), I))
-  blocks_a = blocks(a)
-  return isstored(blocks_a, bI.I...) && isstored(blocks_a[bI.I...], bI.α...)
+  a::AnyAbstractBlockSparseArray, I::Int...
+)
+  return @interface interface(a) isstored(a, I...)
 end
 
 # This circumvents issues passing certain kinds of SubArrays

src/blocksparsearrayinterface/blocksparsearrayinterface.jl

@@ -99,6 +99,13 @@ struct BlockSparseArrayInterface <: AbstractBlockSparseArrayInterface end
 @interface ::AbstractBlockSparseArrayInterface BlockArrays.blocks(a::AbstractArray) =
   error("Not implemented")
 
+@interface ::AbstractBlockSparseArrayInterface function SparseArraysBase.isstored(
+   a::AnyAbstractBlockSparseArray{<:Any,N}, I::Vararg{Int,N}
+ ) where {N}
+   bI = BlockIndex(findblockindex.(axes(a), I))
+   return isstored(blocks_a, bI.I...) && isstored(blocks_a[bI.I...], bI.α...)
+ end
+
 @interface ::AbstractBlockSparseArrayInterface function Base.getindex(
   a::AbstractArray{<:Any,N}, I::Vararg{Int,N}
 ) where {N}