Use ArrayInterfaceBlockBandedMatrices in tests

Author: ChrisRackauckas

Project.toml

@@ -31,6 +31,7 @@ VertexSafeGraphs = "0.2"
 julia = "1.6"
 
 [extras]
+ArrayInterfaceBlockBandedMatrices = "5331f1e9-51c7-46b0-a9b0-df4434785e0a"
 BandedMatrices = "aae01518-5342-5314-be14-df237901396f"
 BlockBandedMatrices = "ffab5731-97b5-5995-9138-79e8c1846df0"
 IterativeSolvers = "42fd0dbc-a981-5370-80f2-aaf504508153"
@@ -43,4 +44,4 @@ Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 Zygote = "e88e6eb3-aa80-5325-afca-941959d7151f"
 
 [targets]
-test = ["Test", "BandedMatrices", "BlockBandedMatrices", "IterativeSolvers", "Pkg", "Random", "SafeTestsets", "Zygote", "SparsityDetection", "StaticArrays"]
+test = ["Test", "ArrayInterfaceBlockBandedMatrices", "BandedMatrices", "BlockBandedMatrices", "IterativeSolvers", "Pkg", "Random", "SafeTestsets", "Zygote", "SparsityDetection", "StaticArrays"]

README.md

@@ -317,3 +317,12 @@ These all have the same interface, where `J*v` utilizes the out-of-place
 Jacobian-vector or Hessian-vector function, whereas `mul!(res,J,v)` utilizes
 the appropriate in-place versions. To update the location of differentiation
 in the operator, simply mutate the vector `u`: `J.u .= ...`.
+
+# Note about sparse differentiation of BandedMatrices and BlockBandedMatrices
+
+These two matrix types need the dependencies ArrayInterfaceBandedMatrices.jl and
+ArrayInterfaceBlockBandedMatrices.jl to basically work with any functionality
+(anywhere). For now, the right thing to do is to add these libraries and do
+`import` on them if you are using BandedMatrices.jl or BlockBandedMatrices.jl
+for sparsity patterns. In the future, those two packages should just depend on
+ArrayInterface.jl and remove this issue entirely from the user space.