Hook into new factorization dispatch mechanisms

src/solvers/cholmod.jl

@@ -1433,10 +1433,16 @@ true
 [^DavisHager2009]: Davis, Timothy A., & Hager, W. W. (2009). Dynamic Supernodes in Sparse Cholesky Update/Downdate and Triangular Solves. ACM Trans. Math. Softw., 35(4). [doi:10.1145/1462173.1462176](https://doi.org/10.1145/1462173.1462176)
 """
 cholesky(A::Union{SparseMatrixCSC{T}, SparseMatrixCSC{Complex{T}},
-    Symmetric{T, <:SparseMatrixCSC{T}},
-    Hermitian{Complex{T}, <:SparseMatrixCSC{Complex{T}}},
-    Hermitian{T, <:SparseMatrixCSC{T}}};
-    kws...) where {T<:Real} = cholesky(Sparse(A); kws...)
+                    RealHermSymComplexHerm{T,<:SparseMatrixCSC}}; kws...) where {T<:Real} =
+    cholesky(Sparse(A); kws...)
+
+LinearAlgebra._cholesky(A::Union{SparseMatrixCSC{T}, SparseMatrixCSC{Complex{T}},
+    RealHermSymComplexHerm{T,<:SparseMatrixCSC}};
+    kws...) where {T<:Real} = cholesky(A; kws...)
+LinearAlgebra._cholesky(A::Union{SparseMatrixCSC{T}, SparseMatrixCSC{Complex{T}},
+    RealHermSymComplexHerm{T,<:SparseMatrixCSC}}, ::LinearAlgebra.PivotingStrategy;
+    kws...) where {T<:Real} =
+    error("Pivoting strategies are not supported for `SparseMatrixCSC`s")
 
 function ldlt!(F::Factor{Tv}, A::Sparse{Tv};
                shift::Real=0.0, check::Bool = true) where Tv

src/solvers/spqr.jl

@@ -230,6 +230,11 @@
     let B=A
         qr(_unsafe_unfix(B); tol, ordering)
     end
+
+LinearAlgebra._qr(A::SparseMatrixCSC; kwargs...) = qr(A; kwargs...)
+LinearAlgebra._qr(::SparseMatrixCSC, ::LinearAlgebra.PivotingStrategy; kwargs...) =
+    error("Pivoting Strategies are not supported for `SparseMatrixCSC`s")
+
 function LinearAlgebra.lmul!(Q::QRSparseQ, A::StridedVecOrMat)
     if size(A, 1) != size(Q, 1)
         throw(DimensionMismatch("size(Q) = $(size(Q)) but size(A) = $(size(A))"))

src/solvers/umfpack.jl

@@ -407,6 +407,11 @@
 lu(A::AdjOrTrans{T,S}; check::Bool = true) where {T<:UMFVTypes, S<:AbstractSparseMatrixCSC{T}} =
     lu(copy(A); check)
 
+LinearAlgebra._lu(A::AbstractSparseMatrixCSC; kwargs...) =
+    lu(A; kwargs...)
+LinearAlgebra._lu(::AbstractSparseMatrixCSC, ::LinearAlgebra.PivotingStrategy; kwargs...) =
+    error("Pivoting Strategies are not supported by `SparseMatrixCSC`s")
+
 """
     lu!(F::UmfpackLU, A::AbstractSparseMatrixCSC; check=true, reuse_symbolic=true, q=nothing) -> F::UmfpackLU
 

test/cholmod.jl

@@ -10,7 +10,7 @@ using Serialization
 using LinearAlgebra:
     I, cholesky, cholesky!, det, diag, eigmax, ishermitian, isposdef, issuccess,
     issymmetric, ldlt, ldlt!, logdet, norm, opnorm, Diagonal, Hermitian, Symmetric,
-    PosDefException, ZeroPivotException
+    PosDefException, ZeroPivotException, RowMaximum
 using SparseArrays
 using SparseArrays: getcolptr
 using SparseArrays.LibSuiteSparse
@@ -972,6 +972,16 @@ end
     @test residual < 1e-6 
 end
 
+@testset "wrapped sparse matrices" begin
+    A = I + sprand(10, 10, 0.1); A = A'A
+    @test issuccess(cholesky(view(A, :, :)))
+    @test issuccess(cholesky(Symmetric(view(A, :, :))))
+    @test_throws ErrorException cholesky(view(A, :, :), RowMaximum())
+    # turn on once two-arg cholesky is made to forward any PivotingStrategy argument
+    # @test_throws ErrorException cholesky(A, NoPivot())
+    # @test_throws ErrorException cholesky(view(A, :, :), NoPivot())
+end
+
 end # Base.USE_GPL_LIBS
 
 end # module