Allocate correct buffer length in to_hypre_data(::MatrixAssembler)

This patch fixes the buffer length in to_hypre_data(::MatrixAssembler).
Previously the buffer was always too long, which was not problematic for
correctness, but it is unnecessary. This patch also adds some assertions
to check the internal consistency of the buffer lengths.

src/HYPRE.jl

@@ -203,6 +203,7 @@ function Internals.to_hypre_data(A::SparseMatrixCSC, ilower, iupper)
             values[k] = val
         end
     end
+    @assert nrows == length(ncols) == length(rows)
     return nrows, ncols, rows, cols, values
 end
 
@@ -233,6 +234,7 @@ function Internals.to_hypre_data(A::SparseMatrixCSR, ilower, iupper)
         end
     end
     @assert nnz == k
+    @assert nrows == length(ncols) == length(rows)
     return nrows, ncols, rows, cols, values
 end
 
@@ -354,6 +356,7 @@ function Internals.to_hypre_data(A::SparseMatrixCSC, r::IndexRange, c::IndexRang
             values[k] = val
         end
     end
+    @assert nrows == length(ncols) == length(rows)
     return nrows, ncols, rows, cols, values
 end
 
@@ -390,6 +393,7 @@ function Internals.to_hypre_data(A::SparseMatrixCSR, r::IndexRange, c::IndexRang
         end
     end
     @assert nnz == k
+    @assert nrows == length(ncols) == length(rows)
     return nrows, ncols, rows, cols, values
 end
 
@@ -633,11 +637,11 @@ end
 
 function Internals.to_hypre_data(A::HYPREMatrixAssembler, a::Matrix, I::Vector, J::Vector)
     size(a, 1) == length(I) || error("mismatching number of rows")
-    size(a, 2) == length(J) || error("mismatch number of cols")
+    size(a, 2) == length(J) || error("mismatching number of cols")
     nrows = HYPRE_Int(length(I))
     # Resize cache vectors
     ncols = resize!(A.ncols, nrows)
-    rows = resize!(A.rows, length(a))
+    rows = resize!(A.rows, nrows)
     cols = resize!(A.cols, length(a))
     values = resize!(A.values, length(a))
     # Fill vectors
@@ -650,6 +654,7 @@ function Internals.to_hypre_data(A::HYPREMatrixAssembler, a::Matrix, I::Vector,
         values[idx] = a[i, j]
     end
     @assert idx == length(a)
+    @assert nrows == length(ncols) == length(rows)
     return nrows, ncols, rows, cols, values
 end