Disable partial linear indexing for non-1 arrays, but allow partial indexing

Author: timholy

base/abstractarray.jl

@@ -365,7 +365,7 @@ function checkbounds_indices(::Type{Bool}, IA::Tuple, I::Tuple{Any})
     @_inline_meta
     checkbounds_linear_indices(Bool, IA, I[1])
 end
-function checkbounds_linear_indices(::Type{Bool}, IA::Tuple, i)
+function checkbounds_linear_indices(::Type{Bool}, IA::Tuple{Vararg{OneTo}}, i)
     @_inline_meta
     if checkindex(Bool, IA[1], i)
         return true
@@ -375,6 +375,10 @@ function checkbounds_linear_indices(::Type{Bool}, IA::Tuple, i)
     end
     return false
 end
+function checkbounds_linear_indices(::Type{Bool}, IA::Tuple{AbstractUnitRange,Vararg{AbstractUnitRange}}, i)
+    @_inline_meta
+    checkindex(Bool, IA[1], i)
+end
 function checkbounds_linear_indices(::Type{Bool}, IA::Tuple, i::Union{Slice,Colon})
     partial_linear_indexing_warning_lookup(length(IA))
     true
@@ -856,11 +860,20 @@ function _to_subscript_indices{T,N}(A::AbstractArray{T,N}, I::Int...) # TODO: DE
     J, Jrem = IteratorsMD.split(I, Val{N})
     _to_subscript_indices(A, J, Jrem)
 end
-function _to_subscript_indices(A::AbstractArray, J::Tuple, Jrem::Tuple{})
+_to_subscript_indices(A::AbstractArray, J::Tuple, Jrem::Tuple{}) =
+    __to_subscript_indices(A, indices(A), J, Jrem)
+# We allow partial linear indexing deprecation for OneTo arrays
+function __to_subscript_indices(A::AbstractArray, ::Tuple{Vararg{OneTo}}, J::Tuple, Jrem::Tuple{})
     @_inline_meta
     sz = _remaining_size(J, indices(A))    # compute trailing size (overlapping the final index)
     (front(J)..., _unsafe_ind2sub(sz, last(J))...) # (maybe) extend the last index
 end
+# After the partial linear indexing deprecation is removed, this next method can
+# become the new normal. For now, it's limited to non-OneTo arrays.
+function __to_subscript_indices(A::AbstractArray, ::Tuple{AbstractUnitRange,Vararg{AbstractUnitRange}}, J::Tuple, Jrem::Tuple{})
+    @_inline_meta
+    (J..., map(first, tail(_remaining_size(J, indices(A))))...)
+end
 _to_subscript_indices(A, J::Tuple, Jrem::Tuple) = J # already bounds-checked, safe to drop
 _to_subscript_indices{T,N}(A::AbstractArray{T,N}, I::Vararg{Int,N}) = I
 _remaining_size(::Tuple{Any}, t::Tuple) = t

test/offsetarray.jl

@@ -30,6 +30,12 @@ S = OffsetArray(view(A0, 1:2, 1:2), (-1,2))   # LinearSlow
 @test_throws BoundsError S[1,1]
 @test_throws BoundsError A[0,3,2]
 @test_throws BoundsError S[0,3,2]
+# partial indexing
+S3 = OffsetArray(view(reshape(collect(1:4*3*2), 4, 3, 2), 1:3, 1:2, :), (-1,-2,1))
+@test S3[1,-1] == 2
+@test S3[1,0] == 6
+@test_throws BoundsError S3[1,1]
+@test_throws BoundsError S3[1,-2]
 
 # Vector indexing
 @test A[:, 3] == S[:, 3] == OffsetArray([1,2], (A.offsets[1],))