diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index f76956d2..5fd2b69e 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -56,8 +56,7 @@ jobs:
             Pkg.develop(PackageSpec(path = pwd()))
             Pkg.add(name = "Aqua", version = "0.8")
             using Aqua, SuiteSparseGraphBLAS
-            # ambiguities: ~190 pre-existing.
-            Aqua.test_all(SuiteSparseGraphBLAS; ambiguities = false)'
+            Aqua.test_all(SuiteSparseGraphBLAS)'
   docs:
     name: Documentation
     runs-on: ubuntu-latest
diff --git a/src/abstractgbarray.jl b/src/abstractgbarray.jl
index 2ffa7447..4033d697 100644
--- a/src/abstractgbarray.jl
+++ b/src/abstractgbarray.jl
@@ -287,6 +287,7 @@ Base.reshape(
     dims::Tuple{Union{Integer, Base.OneTo}, Vararg{Union{Integer, Base.OneTo}}};
     bycol = true
 ) = reshape(A, dims...; bycol)
+Base.reshape(A::AbstractGBMatrix, dims::Tuple{Integer, Vararg{Integer}}; bycol = true) = reshape(A, map(Int, dims)...; bycol)
 
 function Base.reshape(A::AbstractGBMatrix, ::Colon; bycol = true)
     out = similar(A, length(A))
@@ -526,7 +527,7 @@ for T ∈ valid_vec
     end
     func = Symbol(prefix, :_Matrix_assign_, suffix(T))
     @eval begin
-        function _assign(C::AbstractGBMatrix{$T}, x, I, ni, J, nj, mask, accum, desc)
+        function _assign(C::AbstractGBMatrix{$T}, x::$T, I, ni, J, nj, mask, accum, desc)
             @wraperror LibGraphBLAS.$func(C, mask, accum, x, I, ni, J, nj, desc)
             return x
         end
@@ -852,7 +853,7 @@ for T ∈ valid_vec
     # Getindex functions
     func = Symbol(prefix, :_Matrix_extractElement_, suffix(T))
     @eval begin
-        function Base.getindex(v::GBVector{$T}, i::Integer)
+        function Base.getindex(v::AbstractGBVector{$T}, i::Integer)
             x = Ref{$T}()
             result = LibGraphBLAS.$func(x, v, LibGraphBLAS.GrB_Index(decrement!(i)), 0)
             if result == LibGraphBLAS.GrB_SUCCESS
@@ -934,7 +935,7 @@ function Base.setindex!(v::AbstractGBVector{T}, x, i::Integer) where {T}
     return LibGraphBLAS.GrB_Matrix_setElement_UDT(v, Ref(x), LibGraphBLAS.GrB_Index(decrement!(i)), 0)
 end
 
-function Base.getindex(v::GBVector{T}, i::Integer) where {T}
+function Base.getindex(v::AbstractGBVector{T}, i::Integer) where {T}
     x = Ref{T}()
     result = LibGraphBLAS.GrB_Matrix_extractElement_UDT(x, v, LibGraphBLAS.GrB_Index(decrement!(i)), 0)
     if result == LibGraphBLAS.GrB_SUCCESS
@@ -973,6 +974,8 @@ function SparseArrays.nonzeroinds(v::GBVector{T}) where {T}
     return increment!(I)
 end
 
+build!(v::AbstractGBVector{T}, I::Vector{<:Integer}, X::AbstractVector; combine = +) where T =
+    invoke(build!, Tuple{AbstractGBVector{T}, AbstractVector{<:Integer}, AbstractVector}, v, I, X; combine)
 function build!(v::AbstractGBVector{T}, I::Vector{<:Integer}, x::T2) where {T, T2}
     _canbeoutput(v) || throw(ShallowException())
     nnz(v) == 0 || throw(OutputNotEmptyError("Cannot build vector with existing elements"))
@@ -1066,22 +1069,21 @@ function Base.getindex(
     return x
 end
 
-function Base.getindex(
-    u::AbstractGBVector, I;
-    mask = nothing, accum = nothing, desc = nothing
-)
-    return extract(u, I; mask, accum, desc)
-end
 
 function Base.getindex(u::AbstractGBVector, ::Colon; mask = nothing, accum = nothing, desc = nothing)
     return extract(u, :)
 end
 
-function Base.getindex(
-    u::AbstractGBVector, i::Union{Vector, UnitRange, StepRange};
-    mask = nothing, accum = nothing, desc = nothing
-)
-    return extract(u, i; mask, accum, desc)
+# Typed rather than a catch-all, so these don't clash with SparseArrays' AbstractSparseVector methods.
+for IT in (:AbstractVector, :AbstractUnitRange)
+    @eval function Base.getindex(u::AbstractGBVector, I::$IT; mask = nothing, accum = nothing, desc = nothing)
+        return extract(u, I; mask, accum, desc)
+    end
+end
+for IT in (:(AbstractVector{Bool}), :(AbstractUnitRange{Bool})) # logical indexing
+    @eval function Base.getindex(u::AbstractGBVector, I::$IT; mask = nothing, accum = nothing, desc = nothing)
+        return extract(u, findall(I); mask, accum, desc)
+    end
 end
 
 
diff --git a/src/convert.jl b/src/convert.jl
index 896edd54..923dce8e 100644
--- a/src/convert.jl
+++ b/src/convert.jl
@@ -36,3 +36,5 @@ end
 # TODO: Implement this? 
 Base.convert(::Type{M}, ::AbstractGBArray; fill = nothing) where {M<:AbstractGBShallowArray} = 
     throw(ArgumentError("Cannot convert into a shallow array."))
+Base.convert(::Type{M}, ::AbstractGBVector; fill = nothing) where {M<:AbstractGBShallowArray{<:Any, <:Any, <:Any, <:Any, <:Any, <:Any, 1}} =
+    throw(ArgumentError("Cannot convert into a shallow array."))
diff --git a/src/iterator.jl b/src/iterator.jl
index 6835fea3..bd014600 100644
--- a/src/iterator.jl
+++ b/src/iterator.jl
@@ -284,7 +284,10 @@ function Base.iterate(I::VectorIterator)
 end
 Base.iterate(I::VectorIterator, ::Nothing) = inext(I)
 
-Base.getindex(A::AbstractArray, I::GxBIterator) = getindex(A, getrow(I), getcol(I))
-Base.getindex(A::AbstractArray, v::VectorIterator) = getindex(A, v.iterator)
-Base.setindex!(A::AbstractArray, x, I::GxBIterator) = setindex!(A, x, getrow(I), getcol(I))
-Base.setindex!(A::AbstractArray, x, v::VectorIterator) = setindex!(A, x, v.iterator)
\ No newline at end of file
+# Index a matrix at an iterator's position. Restricted to GraphBLAS and dense matrices to avoid
+# ambiguities with SparseArrays' getindex methods.
+const _IterIndexable = Union{AbstractGBMatrix, DenseMatrix}
+Base.getindex(A::_IterIndexable, I::GxBIterator) = getindex(A, getrow(I), getcol(I))
+Base.getindex(A::_IterIndexable, v::VectorIterator) = getindex(A, v.iterator)
+Base.setindex!(A::_IterIndexable, x, I::GxBIterator) = setindex!(A, x, getrow(I), getcol(I))
+Base.setindex!(A::_IterIndexable, x, v::VectorIterator) = setindex!(A, x, v.iterator)
\ No newline at end of file
diff --git a/src/operations/concat.jl b/src/operations/concat.jl
index 8bfd128d..e18cdf0e 100644
--- a/src/operations/concat.jl
+++ b/src/operations/concat.jl
@@ -37,6 +37,6 @@ vcat!(C, A::GBArrayOrTranspose...) = cat!(C, collect(A))
 Base.vcat(A::GBArrayOrTranspose...) = cat(collect(A))
 
 hcat!(C, A::GBArrayOrTranspose...) = cat!(C, permutedims(collect(A)))
-Base.hcat(A::GBArrayOrTranspose...) = cat(permutedims(collect(A)))
+Base.hcat(A::GBArrayOrTranspose, B::GBArrayOrTranspose...) = cat(permutedims(collect((A, B...))))
 
 # TODO split. I don't necessarily see a great need for split though. We have indexing/slicing.
\ No newline at end of file
diff --git a/src/operations/ewise.jl b/src/operations/ewise.jl
index a2a57e1f..09522072 100644
--- a/src/operations/ewise.jl
+++ b/src/operations/ewise.jl
@@ -422,12 +422,12 @@ eunion(
 ) = eunion(A, getfill(A), B, getfill(B), op; mask, accum, desc)
 
 eunion(
-    A::GBArrayOrTranspose, α, B::GBArrayOrTranspose, op::Function = +; 
+    A::GBArrayOrTranspose, α::Number, B::GBArrayOrTranspose, op::Function = +; 
     mask = nothing, accum = nothing, desc = nothing
 ) = eunion(A, α, B, getfill(B), op; mask, accum, desc)
 
 eunion(
-    A::GBArrayOrTranspose, B::GBArrayOrTranspose, β, op::Function = +; 
+    A::GBArrayOrTranspose, B::GBArrayOrTranspose, β::Number, op::Function = +; 
     mask = nothing, accum = nothing, desc = nothing
 ) = eunion(A, getfill(A), B, β, op; mask, accum, desc)
 
@@ -442,12 +442,12 @@ eunion!(
 ) = eunion!(C, A, getfill(A), B, getfill(B), op; mask, accum, desc)
 
 eunion!(
-    C::GBVecOrMat, A::GBArrayOrTranspose, α, B::GBArrayOrTranspose, op::Function = +; 
+    C::GBVecOrMat, A::GBArrayOrTranspose, α::Number, B::GBArrayOrTranspose, op::Function = +; 
     mask = nothing, accum = nothing, desc = nothing
 ) = eunion!(C, A, α, B, getfill(B), op; mask, accum, desc)
 
 eunion!(
-    C::GBVecOrMat, A::GBArrayOrTranspose, B::GBArrayOrTranspose, β, op::Function = +; 
+    C::GBVecOrMat, A::GBArrayOrTranspose, B::GBArrayOrTranspose, β::Number, op::Function = +; 
     mask = nothing, accum = nothing, desc = nothing
 ) = eunion!(C, A, getfill(A), B, β, op; mask, accum, desc)
 
diff --git a/src/operations/map.jl b/src/operations/map.jl
index f33fc454..2f6e9166 100644
--- a/src/operations/map.jl
+++ b/src/operations/map.jl
@@ -69,6 +69,9 @@ function apply!(
     end
     return C
 end
+# Neither of the 3-arg forms applies when both are arrays and the first can't be an output.
+apply!(op, ::GBArrayOrTranspose, ::GBArrayOrTranspose; mask = nothing, accum = nothing, desc = nothing) =
+    throw(ArgumentError("apply! needs a non-transposed output array; for two arrays use `eadd` or `emul`."))
 function apply!(
     op, A::GBArrayOrTranspose, x;
     mask = nothing, accum = nothing, desc = nothing
@@ -142,11 +145,6 @@ function Base.map!(f, A::GBArrayOrTranspose; mask = nothing, accum = nothing, de
     apply!(f, A, A; mask, accum, desc)
 end
 
-Base.:*(x, u::GBArrayOrTranspose; mask = nothing, accum = nothing, desc = nothing) =
-    apply(*, x, u; mask, accum, desc)
-Base.:*(u::GBArrayOrTranspose, x; mask = nothing, accum = nothing, desc = nothing) =
-    apply(*, u, x; mask, accum, desc)
-
 Base.:*(x::Number, u::GBArrayOrTranspose; mask = nothing, accum = nothing, desc = nothing) =
     apply(*, x, u; mask, accum, desc)
 Base.:*(u::GBArrayOrTranspose, x::Number; mask = nothing, accum = nothing, desc = nothing) =
diff --git a/src/operations/mul.jl b/src/operations/mul.jl
index cd8b97fa..91f04ce9 100644
--- a/src/operations/mul.jl
+++ b/src/operations/mul.jl
@@ -1,3 +1,6 @@
+# A semiring given as a (⊕, ⊗) tuple or a TypedSemiring. Typed so 3-arg `*` can't clash with A * B * C.
+const SemiringSpec = Union{Tuple, TypedSemiring}
+
 function LinearAlgebra.mul!(
     C::GBVecOrMat,
     A::GBArrayOrTranspose,
@@ -86,7 +89,7 @@ The operator syntax `A * B` can be used when the default semiring is desired, an
 function Base.:*(
     A::GBArrayOrTranspose,
     B::GBArrayOrTranspose,
-    op = (+, *);
+    op::SemiringSpec = (+, *);
     mask = nothing,
     accum = nothing,
     desc = nothing
@@ -108,7 +111,7 @@ end
 function Base.:*(
     A::VecMatOrTrans,
     B::GBArrayOrTranspose,
-    op = (+, *);
+    op::SemiringSpec = (+, *);
     mask = nothing,
     accum = nothing,
     desc = nothing
@@ -119,7 +122,7 @@ end
 function Base.:*(
     A::GBArrayOrTranspose,
     B::VecMatOrTrans,
-    op = (+, *);
+    op::SemiringSpec = (+, *);
     mask = nothing,
     accum = nothing,
     desc = nothing
@@ -142,11 +145,17 @@ function Base.:*(v::Transpose{<:Real, <:AbstractGBVector{T, F, O} where O} where
     u::AbstractGBVector{T, F, O} where {T, F, O})
     *(v, u, (+, *))
 end
+# Dense matrix times a GraphBLAS vector also matches SparseArrays' triangular/adjoint * sparse vector methods.
+Base.:*(A::DenseMatrix, v::AbstractGBVector) = *(A, v, (+, *))
+Base.:*(A::Transpose{<:Any, <:DenseMatrix}, v::AbstractGBVector) = *(A, v, (+, *))
+Base.:*(A::Transpose{<:Real, <:DenseMatrix}, v::AbstractGBVector) = *(A, v, (+, *))
+# u' * x for real dense x, also matched by LinearAlgebra's dot-product method.
+Base.:*(v::Transpose{<:Real, <:AbstractGBVector}, u::DenseVector{<:Real}) = *(v, u, (+, *))
 
 function Base.:*(
     A::Transpose{<:T, <:DenseVecOrMat},
     B::GBArrayOrTranspose,
-    op = (+, *);
+    op::SemiringSpec = (+, *);
     mask = nothing,
     accum = nothing,
     desc = nothing
@@ -157,7 +166,7 @@ end
 function Base.:*(
     A::GBArrayOrTranspose,
     B::Transpose{<:T, <:DenseVecOrMat},
-    op = (+, *);
+    op::SemiringSpec = (+, *);
     mask = nothing,
     accum = nothing,
     desc = nothing
@@ -226,12 +235,12 @@ function LinearAlgebra.mul!(C::GBVecOrMat, A::G, D::Diagonal, op = (+, *); mask
         SuiteSparseGraphBLAS.AbstractGBArray{T, F, O, 2} where {T, F, O}}}
     return mul!(C, A, G(D), op; mask, accum, desc)
 end
-function Base.:*(D::Diagonal, A::G, op = (+, *); mask = nothing, accum = nothing, desc = nothing) where
+function Base.:*(D::Diagonal, A::G, op::SemiringSpec = (+, *); mask = nothing, accum = nothing, desc = nothing) where
     {G <: Union{Transpose{T, <:SuiteSparseGraphBLAS.AbstractGBArray{T1, F, O}} where {T, T1, F, O},
         SuiteSparseGraphBLAS.AbstractGBArray{T, F, O, 2} where {T, F, O}}}
     return *(G(D), A, op; mask, accum, desc)
 end
-function Base.:*(A::G, D::Diagonal, op = (+, *); mask = nothing, accum = nothing, desc = nothing) where
+function Base.:*(A::G, D::Diagonal, op::SemiringSpec = (+, *); mask = nothing, accum = nothing, desc = nothing) where
     {G <: Union{Transpose{T, <:SuiteSparseGraphBLAS.AbstractGBArray{T1, F, O}} where {T, T1, F, O},
         SuiteSparseGraphBLAS.AbstractGBArray{T, F, O, 2} where {T, F, O}}}
     return *(A, G(D), op; mask, accum, desc)
diff --git a/src/operations/operationutils.jl b/src/operations/operationutils.jl
index 7a05dfe4..c926762d 100644
--- a/src/operations/operationutils.jl
+++ b/src/operations/operationutils.jl
@@ -122,6 +122,9 @@ _promotefill(x, ::AbstractGBArray{<:Any, Nothing}, op) = nothing
 _promotefill(::AbstractGBArray{<:Any, Nothing}, ::AbstractGBArray{<:Any, <:Any}, op) = nothing
 _promotefill(::AbstractGBArray{<:Any, <:Any}, ::AbstractGBArray{<:Any, Nothing}, op) = nothing
 
+_promotefill(::AbstractGBArray{<:Any, Missing}, ::AbstractGBArray{<:Any, Nothing}, op) = missing
+_promotefill(::AbstractGBArray{<:Any, Nothing}, ::AbstractGBArray{<:Any, Missing}, op) = missing
+
 _promotefill(x, op) = x
 
 function _promotefill(x::AbstractGBArray{<:Any, T}, y::AbstractGBArray{<:Any, U}, op) where {T, U}
diff --git a/src/operators/monoids.jl b/src/operators/monoids.jl
index ef224843..41e980d7 100644
--- a/src/operators/monoids.jl
+++ b/src/operators/monoids.jl
@@ -40,6 +40,7 @@ function typedmonoid(m::Monoid{F, I, Term}, ::Type{T}) where {F, I, Term, T}
 end
 
 typedmonoid(op::TypedMonoid, x...) = op
+typedmonoid(op::TypedMonoid, ::Type) = op
 
 # We default to no available monoid.
 defaultmonoid(f::F, ::Type{T}) where {F, T} = throw(
diff --git a/src/operators/selectops.jl b/src/operators/selectops.jl
index 121fec30..7dc140f1 100644
--- a/src/operators/selectops.jl
+++ b/src/operators/selectops.jl
@@ -119,16 +119,16 @@ function rowleq end
 function rowgt end
 const COLLEQ = TypedIndexUnaryOperator{typeof(colleq), Any, Any, Bool}(
     true, false, "GrB_COLLEQ", LibGraphBLAS.GrB_IndexUnaryOp(),colleq)
-indexunaryop(::typeof(colleq), ::Any, ::Any) = COLLEQ
+indexunaryop(::typeof(colleq), ::Type, ::Type) = COLLEQ
 const COLGT = TypedIndexUnaryOperator{typeof(colgt), Any, Any, Bool}(
     true, false, "GrB_OFFDIAG", LibGraphBLAS.GrB_IndexUnaryOp(),colgt)
-indexunaryop(::typeof(colgt), ::Any, ::Any) = COLGT
+indexunaryop(::typeof(colgt), ::Type, ::Type) = COLGT
 const ROWLEQ = TypedIndexUnaryOperator{typeof(rowleq), Any, Any, Bool}(
     true, false, "GrB_OFFDIAG", LibGraphBLAS.GrB_IndexUnaryOp(),rowleq)
-indexunaryop(::typeof(rowleq), ::Any, ::Any) = ROWLEQ
+indexunaryop(::typeof(rowleq), ::Type, ::Type) = ROWLEQ
 const ROWGT = TypedIndexUnaryOperator{typeof(rowgt), Any, Any, Bool}(
     true, false, "GrB_OFFDIAG", LibGraphBLAS.GrB_IndexUnaryOp(),rowgt)
-indexunaryop(::typeof(rowgt), ::Any, ::Any) = ROWGT
+indexunaryop(::typeof(rowgt), ::Type, ::Type) = ROWGT
 
 cardinal_vec = filter(x-> x ∉ [ComplexF64, ComplexF32], valid_vec)
 
@@ -219,7 +219,7 @@ for F ∈ [
     rowgt
 ]
     @eval isindexop(::typeof($F)) = true
-    @eval SuiteSparseGraphBLAS.inferbinarytype(::Any, ::Any, ::typeof($F)) = Bool
+    @eval SuiteSparseGraphBLAS.inferbinarytype(::Type, ::Type, ::typeof($F)) = Bool
 end
 
 end
diff --git a/src/shallowtypes.jl b/src/shallowtypes.jl
index 32b8541d..d5ffacba 100644
--- a/src/shallowtypes.jl
+++ b/src/shallowtypes.jl
@@ -100,8 +100,8 @@ reshape!(::AbstractGBShallowArray, dims...; kwargs...) = throw(ShallowException(
 reshape!(::AbstractGBShallowArray, n; kwargs...) = throw(ShallowException())
 Base.deleteat!(::GBShallowMatrix, i, j) = throw(ShallowException())
 Base.deleteat!(::GBShallowVector, i) = throw(ShallowException())
-Base.resize!(::GBShallowMatrix, nrows, ncols) = throw(ShallowException())
-Base.resize!(::GBShallowVector, nrows) = throw(ShallowException())
+Base.resize!(::GBShallowMatrix, nrows::Integer, ncols::Integer) = throw(ShallowException())
+Base.resize!(::GBShallowVector, nrows::Integer) = throw(ShallowException())
 build!(::GBShallowMatrix{T}, I::AbstractVector, J::AbstractVector, x::T) where T = throw(ShallowException())
 
 LinearAlgebra.Diagonal(v::GBShallowVector) = Diagonal(copy(v))
diff --git a/src/solvers/cholmod.jl b/src/solvers/cholmod.jl
index 24781b90..47570a13 100644
--- a/src/solvers/cholmod.jl
+++ b/src/solvers/cholmod.jl
@@ -237,7 +237,7 @@ end
 
 (\)(L::FactorComponent, B::Adjoint{<:Any,<:AbstractGBMatrix}) = L \ copy(B)
 (\)(L::FactorComponent, B::Transpose{<:Any,<:AbstractGBMatrix}) = L \ copy(B)
-\(adjL::Adjoint{<:Any,<:FactorComponent}, B::Union{VecOrMat,AbstractGBArray}) = (L = adjL.parent; adjoint(L)\B)
+\(adjL::Adjoint{<:Any,<:FactorComponent}, B::AbstractGBArray) = (L = adjL.parent; adjoint(L)\B) # VecOrMat is SparseArrays'
 (\)(L::Factor, B::S) where {S<:AbstractGBMatrix} = S(spsolve(CHOLMOD_A, L, CHOLMOD.Sparse(B, 0)))
 (\)(L::Factor, B::Adjoint{<:Any,<:AbstractGBMatrix}) = L \ copy(B)
 (\)(L::Factor, B::Transpose{<:Any,<:AbstractGBMatrix}) = L \ copy(B)
diff --git a/test/gbarray.jl b/test/gbarray.jl
index 5bfe9f9b..253a8366 100644
--- a/test/gbarray.jl
+++ b/test/gbarray.jl
@@ -71,6 +71,19 @@
             @test Vector(GBVector([1, 3], 2.0, 4)) == [2.0, 0, 2, 0]
             @test Vector(GBVector((3,), 1.0)) == ones(3)
             @test Matrix(GBMatrix((2, 2), 1.0)) == ones(2, 2)
+            @test SuiteSparseGraphBLAS.pack([1.0, 2.0, 3.0])[2] == 2.0 # scalar index on a shallow vector
+            w = GBVector([1.0, 0, 3])
+            @test Vector(w[[true, false, true]]) == [1.0, 3.0] # logical indexing
+            sh = SuiteSparseGraphBLAS.pack([1.0, 2.0])
+            @test_throws SuiteSparseGraphBLAS.ShallowException resize!(sh, 3)
+            @test_throws SuiteSparseGraphBLAS.ShallowException resize!(SuiteSparseGraphBLAS.pack([1.0 2; 3 4]), 3, 3)
+            @test_throws ArgumentError convert(typeof(sh), w)
+            b = SuiteSparseGraphBLAS.build!(GBVector{Float64}(3), [1, 3], [1.0, 2.0])
+            @test Vector(b) == [1.0, 0, 2.0]
+            @test size(reshape(GBMatrix([1.0 2; 3 4]), (Int32(4), Int32(1)))) == (4, 1)
+            mon = SuiteSparseGraphBLAS.Monoids.typedmonoid(+, Float64)
+            @test SuiteSparseGraphBLAS.Monoids.typedmonoid(mon, Float64) === mon
+            @test SuiteSparseGraphBLAS.IndexUnaryOps.indexunaryop(SuiteSparseGraphBLAS.IndexUnaryOps.colleq, Float64, Float64) isa SuiteSparseGraphBLAS.TypedIndexUnaryOperator
         end
     end
 
@@ -155,5 +168,8 @@
         @test isempty(gather(SuiteSparseGraphBLAS.iteratecols(H, 5)))
         @test gather(SuiteSparseGraphBLAS.iteratecols(H, 2:900, SuiteSparseGraphBLAS.IndicesIterator())) ==
             [((1, 2), 1.0), ((7, 2), 2.0), ((3, 900), 3.0)]
+        Hs = H[1:10, 1:3]; D = Matrix(Hs); vals = []
+        for it in SuiteSparseGraphBLAS.iteratecols(Hs, 2, SuiteSparseGraphBLAS.IteratorIterator()); push!(vals, D[it]); end
+        @test vals == [1.0, 2.0] # index a dense matrix at the iterator's position
     end
 end
diff --git a/test/operations/ewise.jl b/test/operations/ewise.jl
index 18a33ecd..1eb035d4 100644
--- a/test/operations/ewise.jl
+++ b/test/operations/ewise.jl
@@ -8,4 +8,11 @@
     #emul correctness
     @test emul(m, n, ^)[3, 2] == m[3,2] ^ n[3,2]
     @test eltype(m .== n) == Bool
+
+    # eunion shortcut forms with a scalar fill for one side
+    E = GBMatrix([1.0 2; 3 4]); E2 = GBMatrix([1, 2], [1, 2], [10.0, 20.0], 2, 2)
+    @test Matrix(eunion(E, 0.0, E2, +)) == Matrix(eunion(E, getfill(E), E2, getfill(E2), +))
+    @test Matrix(eunion(E, E2, 0.0, +)) == Matrix(E) + Matrix(E2)
+    @test Matrix(eunion!(similar(E), E, 0.0, E2, +)) == Matrix(E) + Matrix(E2)
+    @test Matrix(eunion!(similar(E), E, E2, 0.0, +)) == Matrix(E) + Matrix(E2)
 end
diff --git a/test/operations/map.jl b/test/operations/map.jl
index 6744b496..c04ba3f1 100644
--- a/test/operations/map.jl
+++ b/test/operations/map.jl
@@ -10,4 +10,5 @@
     # Julia will map over the entire array, rather than just nnz.
     # so just test [1,1]
     @test map((x) -> 1.5, n)[nonzero...] == map((x) -> 1.5, m)[nonzero...]
+    @test_throws ArgumentError apply!(+, transpose(n), n)
 end
diff --git a/test/operations/mul.jl b/test/operations/mul.jl
index 3bef20d9..9feb20de 100644
--- a/test/operations/mul.jl
+++ b/test/operations/mul.jl
@@ -32,4 +32,14 @@
     @test mul!(copy(Y), A, X, 2, 3) ≈ 2 * S * X + 3 * Y
     @test mul!(zeros(ComplexF64, 15), A', y) ≈ S' * y
     @test mul!(view(zeros(ComplexF64, 25), 3:22), A, view([x; x], 16:30)) ≈ S * x
+
+    # previously ambiguous products
+    R = GBMatrix([1.0 2; 3 4]); r = [3.0, 4.0]
+    @test (GBVector([1.0, 2.0])' * r)[1, 1] == 11.0
+    @test R * sparse(r) ≈ [11.0, 25.0]
+    @test R * view([0.0, 3, 4], 2:3) ≈ [11.0, 25.0]
+    M = [1.0 2; 3 4]; g = GBVector([1.0, 1.0])
+    @test Vector(M * g) == M * [1.0, 1.0]
+    @test Vector(transpose(M) * g) == transpose(M) * [1.0, 1.0]
+    @test Vector(transpose(ComplexF64.(M)) * GBVector(ComplexF64[1, 1])) == transpose(M) * [1.0, 1.0]
 end
diff --git a/test/operations/operationutils.jl b/test/operations/operationutils.jl
index 418100df..f19a6e76 100644
--- a/test/operations/operationutils.jl
+++ b/test/operations/operationutils.jl
@@ -22,5 +22,8 @@ end
     @test (mask = _handlemask!(d, ~~Structural(v)); 
         !d.complement_mask && d.structural_mask && mask isa GBVector)
 end
+    @test SuiteSparseGraphBLAS.inferbinarytype(Float64, Float64, triu) == Bool
+    gm, gn = GBMatrix([1.0 2]; fill = missing), GBMatrix([1.0 2]; fill = nothing)
+    @test SuiteSparseGraphBLAS._promotefill(gm, gn, +) === missing
+    @test SuiteSparseGraphBLAS._promotefill(gn, gm, +) === missing
 end
-    
\ No newline at end of file