Fix non-1 based axes

Author: N5N3

base/multidimensional.jl

@@ -619,16 +619,18 @@ module IteratorsMD
         piter = iter.parent.parent
         ci = CartesianIndices(tail(piter.indices))
         size1 = size(piter, 1)
-        vindʷ = only(iter.indices)
-        vindᵒ = cld(first(vindʷ), size1) : cld(last(vindʷ), size1)
+        offsetʷ = firstindex(piter) - 1
+        vindʷ = only(iter.indices) .- offsetʷ
+        offsetᵒ = firstindex(ci) - 1
+        vindᵒ = cld(first(vindʷ) , size1) : cld(last(vindʷ), size1)
         # Use Generator to make inner loop branchless
         @inline function genouter(i::Int, I::CartesianIndex)
             l, r = first(vindᵒ), last(vindᵒ)
             skip = i == 1 ? first(vindʷ) - 1 - (l - 1) * size1 : 0
             len = i == length(vindᵒ) ? last(vindʷ) - (r - 1) * size1 : size1
             skip, len - skip, I
         end
-        outer = @inbounds view(ci, vindᵒ)
+        outer = @inbounds view(ci, vindᵒ .+ offsetᵒ)
         (genouter(i, I) for (i, I) in Iterators.enumerate(outer))
     end
     @inline simd_inner_length(iter::CartesianPartition, (skip, len, I)::Tuple{Int,Int,CartesianIndex}) = len

test/iterators.jl

@@ -548,7 +548,8 @@ end
                                                          (1,1), (8,8), (11, 13),
                                                          (1,1,1), (8, 4, 2), (11, 13, 17)),
                                                 part in (1, 7, 8, 11, 63, 64, 65, 142, 143, 144)
-    for iter in (CartesianIndices(dims), CartesianIndices(map(d -> 1:2:2d, dims)))
+    for fun in (i -> 1:i, i -> 1:2:2i, i -> Base.IdentityUnitRange(-i:i))
+        iter = CartesianIndices(map(fun, dims))
         P = partition(iter, part)
         for I in P
             @test length(I) == iterate_length(I) == simd_iterate_length(I) == simd_trip_count(I)