Fix IdOffsetRange kwargs constructor given offset ranges (#303)

* fix IdOffsetRange kwargs constructor

* preserve types if indices are 1-based

* no_offset_view in values

* remove test for SOneTo (#301)

* Add tests

* bump version to v1.12.4

Project.toml

@@ -1,6 +1,6 @@
 name = "OffsetArrays"
 uuid = "6fe1bfb0-de20-5000-8ca7-80f57d26f881"
-version = "1.12.3"
+version = "1.12.4"
 
 [deps]
 Adapt = "79e6a3ab-5dfb-504d-930d-738a2a938a0e"

src/axes.jl

@@ -128,10 +128,15 @@ end
 IdOffsetRange(r::IdOffsetRange) = r
 
 # Constructor to make `show` round-trippable
+# try to preserve typeof(values) if the indices are known to be 1-based
+_subtractindexoffset(values, indices::Union{Base.OneTo, IdentityUnitRange{<:Base.OneTo}}, offset) = values
+_subtractindexoffset(values, indices, offset) = _subtractoffset(values, offset)
 function IdOffsetRange(; values::AbstractUnitRange{<:Integer}, indices::AbstractUnitRange{<:Integer})
     length(values) == length(indices) || throw(ArgumentError("values and indices must have the same length"))
+    values_nooffset = no_offset_view(values)
     offset = first(indices) - 1
-    return IdOffsetRange(values .- offset, offset)
+    values_minus_offset = _subtractindexoffset(values_nooffset, indices, offset)
+    return IdOffsetRange(values_minus_offset, offset)
 end
 
 # Conversions to an AbstractUnitRange{Int} (and to an OrdinalRange{Int,Int} on Julia v"1.6") are necessary

test/runtests.jl

@@ -138,6 +138,20 @@ end
     @test_throws MethodError IdOffsetRange(7:9, indices=-1:1)
     @test_throws MethodError IdOffsetRange(-1:1, values=7:9)
 
+    p = IdOffsetRange(1:3, 2)
+    q = IdOffsetRange(values = p .- 2, indices = p)
+    @test same_value(q, 1:3)
+    check_indexed_by(q, p)
+
+    @testset for indices in Any[Base.OneTo(3), IdentityUnitRange(Base.OneTo(3))]
+        p = IdOffsetRange(values = IdOffsetRange(1:3, 2), indices = indices)
+        @test same_value(p, 3:5)
+        check_indexed_by(p, 1:3)
+        q = IdOffsetRange(values = Base.OneTo(3), indices = indices)
+        @test same_value(q, 1:3)
+        @test q isa IdOffsetRange{Int, Base.OneTo{Int}}
+    end
+
     # conversion preserves both the values and the axes, throwing an error if this is not possible
     @test @inferred(oftype(ro, ro)) === ro
     @test @inferred(convert(OffsetArrays.IdOffsetRange{Int}, ro)) === ro