Preserve ranges in indexing with IIUR(::OneTo)

src/OffsetArrays.jl

@@ -349,19 +349,19 @@ end
 
 for OR in [:IIUR, :IdOffsetRange]
     for R in [:StepRange, :StepRangeLen, :LinRange, :UnitRange]
-        @eval @propagate_inbounds Base.getindex(r::$R, s::$OR) = OffsetArray(r[UnitRange(s)], axes(s))
+        @eval @propagate_inbounds Base.getindex(r::$R, s::$OR) = _maybewrapaxes(r[UnitRange(s)], axes(s,1))
     end
 
     # this method is needed for ambiguity resolution
     @eval @propagate_inbounds Base.getindex(r::StepRangeLen{T,<:Base.TwicePrecision,<:Base.TwicePrecision}, s::$OR) where T =
-    OffsetArray(r[UnitRange(s)], axes(s))
+    _maybewrapaxes(r[UnitRange(s)], axes(s,1))
 
     #= Integer UnitRanges may return an appropriate AbstractUnitRange{<:Integer}, as the result may be used in indexing, and
     indexing is faster with ranges =#
     @eval @propagate_inbounds function Base.getindex(r::UnitRange{<:Integer}, s::$OR)
         rs = r[UnitRange(s)]
         offset_s = first(axes(s,1)) - 1
-        IdOffsetRange(UnitRange(rs .- offset_s), offset_s)
+        _maybewrapoffset(rs, offset_s, axes(s,1))
     end
 end
 

src/axes.jl

@@ -158,7 +158,7 @@ end
 @propagate_inbounds Base.getindex(r::IdOffsetRange, i::Integer) = r.parent[i - r.offset] + r.offset
 @propagate_inbounds function Base.getindex(r::IdOffsetRange, s::AbstractUnitRange{<:Integer})
     offset_s = first(axes(s,1)) - 1
-    pr = r.parent[s .- r.offset] .+ (r.offset - offset_s)
+    pr = r.parent[s .- r.offset] .+ r.offset
     _maybewrapoffset(pr, offset_s, axes(s,1))
 end
 # The following method is required to avoid falling back to getindex(::AbstractUnitRange, ::StepRange{<:Integer})

src/utils.jl

@@ -77,5 +77,5 @@ _maybewrapaxes(A::AbstractVector, ax) = OffsetArray(A, ax)
 
 _maybewrapoffset(r::AbstractUnitRange, of, ::Base.OneTo) = no_offset_view(r)
 _maybewrapoffset(r::AbstractVector, of, ::Base.OneTo) = no_offset_view(r)
-_maybewrapoffset(r::AbstractUnitRange, of, ::Any) = IdOffsetRange(UnitRange(r), of)
-_maybewrapoffset(r::AbstractVector, of, axs) = OffsetArray(r .+ of, axs)
+_maybewrapoffset(r::AbstractUnitRange, of, ::Any) = IdOffsetRange(UnitRange(r .- of), of)
+_maybewrapoffset(r::AbstractVector, of, axs) = OffsetArray(r, axs)

test/runtests.jl

@@ -887,6 +887,9 @@ end
             ]
 
             test_indexing_axes_and_vals(r1, r2)
+            if axes(r2, 1) isa Base.OneTo
+                @test r1[r2] isa AbstractRange
+            end
         end
     end
 end