Fix ambiguity of broadcast!(identity, ::SparseVector, ::SparseVector)

Author: martinholters

base/sparse/higherorderfns.jl

@@ -148,7 +148,7 @@ ambiguityfunnel{Tf}(f::Tf, x, y) = _aresameshape(x, y) ? _noshapecheck_map(f, x,
 broadcast(::typeof(+), x::SparseVector, y::SparseVector) = ambiguityfunnel(+, x, y) # base/sparse/sparsevectors.jl:1266
 broadcast(::typeof(-), x::SparseVector, y::SparseVector) = ambiguityfunnel(-, x, y) # base/sparse/sparsevectors.jl:1266
 broadcast(::typeof(*), x::SparseVector, y::SparseVector) = ambiguityfunnel(*, x, y) # base/sparse/sparsevectors.jl:1266
-function broadcast!(::typeof(identity), C::SparseMatrixCSC, A::SparseMatrixCSC) # from #17623, loc?
+function broadcast!{T<:SparseVecOrMat}(::typeof(identity), C::T, A::T) # from #17623, base/broadcast.jl:26
     _checksameshape(C, A); return copy!(C, A)
 end
 

test/sparse/higherorderfns.jl

@@ -86,6 +86,8 @@ end
     @test broadcast(sin, A) == sparse(broadcast(sin, fA))
     @test broadcast!(sin, copy(a), a) == sparse(broadcast!(sin, copy(fa), fa))
     @test broadcast!(sin, copy(A), A) == sparse(broadcast!(sin, copy(fA), fA))
+    @test broadcast!(identity, copy(a), a) == sparse(broadcast!(identity, copy(fa), fa))
+    @test broadcast!(identity, copy(A), A) == sparse(broadcast!(identity, copy(fA), fA))
 end
 
 @testset "broadcast[!] implementation specialized for pairs of (input) sparse vectors/matrices" begin