Check sparse matrix is square before computing condition number

Fixed JuliaLang#12731

Author: Marcus P S

base/sparse/linalg.jl

@@ -490,6 +490,7 @@ end
 
 # cond
 function cond(A::SparseMatrixCSC, p::Real=2)
+    chksquare(A)
     if p == 1
         normA = norm(A, 1)
         normAinv = normestinv(A)

test/sparsedir/sparse.jl

@@ -1078,6 +1078,7 @@ Ar = sprandn(20,20,.5)
 @test_approx_eq_eps cond(Ac,Inf) cond(full(Ac),Inf) 1e-4
 @test_throws ArgumentError cond(A,2)
 @test_throws ArgumentError cond(A,3)
+@test_throws DimensionMismatch cond(spzeros(3,2))
 
 # test sparse matrix normestinv
 Ac = sprandn(20,20,.5) + im* sprandn(20,20,.5)