add parent(r::IdOffsetRange) (#103)

* add parent(r::IdOffsetRange)

* add test for parent(r::IdOffsetRange)

Author: johnnychen94

src/axes.jl

@@ -124,6 +124,7 @@ end
 offset_coerce(::Type{I}, r::AbstractUnitRange) where I<:AbstractUnitRange{T} where T =
     convert(I, r), 0
 
+@inline Base.parent(r::IdOffsetRange) = r.parent
 @inline Base.axes(r::IdOffsetRange) = (Base.axes1(r),)
 @inline Base.axes1(r::IdOffsetRange) = IdOffsetRange(Base.axes1(r.parent), r.offset)
 @inline Base.unsafe_indices(r::IdOffsetRange) = (r,)

test/runtests.jl

@@ -34,6 +34,8 @@ using CatIndices: BidirectionalVector
     @test @inferred(OffsetArrays.IdOffsetRange{Int}(ro))   === ro
     @test @inferred(OffsetArrays.IdOffsetRange{Int16}(ro)) === OffsetArrays.IdOffsetRange(Base.OneTo(Int16(3)))
     @test @inferred(OffsetArrays.IdOffsetRange(ro))        === ro
+    @test parent(ro) === ro.parent
+    @test parent(rs) === rs.parent
     # construction/coercion preserves the values, altering the axes if needed
     r2 = @inferred(typeof(rs)(ro))
     @test typeof(r2) === typeof(rs)