Some fix for ReshapedReinterpretArray

and add more test

base/reinterpretarray.jl

@@ -156,6 +156,7 @@ function strides(a::ReshapedReinterpretArray)
  stp = strides(ap)
  els == elp && return stp
  els < elp && return (1, map(Fix2(*, elp ÷ els), stp)...)
+ stp[1] == 1 || throw(ArgumentError("Parent must be contiguous in the 1st dimension!"))
  return _checked_strides(stp, els ÷ elp)
 end
 

test/reinterpretarray.jl

@@ -157,33 +157,51 @@ let A = collect(reshape(1:20, 5, 4))
  @test reshape(R, :) isa StridedArray
 end
 
+function check_strides(A::AbstractArray)
+ # Make sure stride(A, i) is equivalent with strides(A)[i] (if 1 <= i <= ndims(A))
+ dims = ntuple(identity, ndims(A))
+ map(i -> stride(A, i), dims) == strides(A) || return false
+ # Test strides via value check.
+ for i in eachindex(IndexLinear(), A)
+ A[i] === Base.unsafe_load(pointer(A, i)) || return false
+ end
+ return true
+end
+
 @testset "strides for NonReshapedReinterpretArray" begin
- A = Matrix{Int16}(reshape(1:80, 20, 4))
- for (T, st) in ((Int8, (1, 40)), (Int32, (1, 10)))
- R = reinterpret(T, view(A, :, 1:2))
- @test (stride(R, 1), stride(R, 2)) == strides(R) == st
- R = reinterpret(T, view(A, 1:18, :))
- @test (stride(R, 1), stride(R, 2)) == strides(R) == st
+ A = Array{Int32}(reshape(1:72, 9, 8))
+ for viewax2 in (1:8, 1:2:6, 7:-1:1, 5:-2:1)
+ # dim1 is contiguous
+ for T in (Int16, Float32)
+ @test check_strides(reinterpret(T, view(A, 1:8, viewax2)))
+ end
+ if mod(step(viewax2), 2) == 0
+ @test check_strides(reinterpret(Int64, view(A, 1:8, viewax2)))
+ else
+ @test_throws "Parent's strides" strides(reinterpret(Int64, view(A, 1:8, viewax2)))
+ end
+ # dim1 is not contiguous
+ for T in (Int16, Int64)
+ @test_throws "Parent must" strides(reinterpret(T, view(A, 8:-1:1, viewax2)))
+ end
+ @test check_strides(reinterpret(Float32, view(A, 8:-1:1, viewax2)))
  end
- A = Matrix{Int16}(reshape(1:76, 19, 4))
- R = reinterpret(Int8, view(A, 1:18, :))
- @test (stride(R, 1), stride(R, 2)) == strides(R) == (1, 38)
- R = reinterpret(Int32, view(A, 1:18, :))
- @test_throws ArgumentError strides(R)
- R = reinterpret(Int8, view(A, 18:-1:1, :))
- @test_throws ArgumentError strides(R)
- R = reinterpret(Int8, view(A, 1:2:18, :))
- @test_throws ArgumentError strides(R)
 end
 
 @testset "strides for ReshapedReinterpretArray" begin
- A = Matrix{Int16}(reshape(1:12, 3, 4))
- R = reinterpret(reshape, Int8, view(A, 1:2, 1:2))
- @test (stride(R, 1), stride(R, 2), stride(R, 3)) == strides(R) == (1, 2, 6)
- R = reinterpret(reshape, NTuple{3,Int16}, view(A, 1:3, 1:2))
- @test (stride(R, 1),) == strides(R) == (1,)
- R = reinterpret(reshape, Int32, view(A, 1:2, 1:2))
- @test_throws ArgumentError strides(R)
+ A = Array{Int32}(reshape(1:192, 3, 8, 8))
+ for viewax1 in (1:8, 1:2:8, 8:-1:1, 8:-2:1), viewax2 in (1:2, 4:-1:1)
+ for T in (Int16, Float32)
+ @test check_strides(reinterpret(reshape, T, view(A, 1:2, viewax1, viewax2)))
+ @test check_strides(reinterpret(reshape, T, view(A, 1:2:3, viewax1, viewax2)))
+ end
+ if mod(step(viewax1), 2) == 0
+ @test check_strides(reinterpret(reshape, Int64, view(A, 1:2, viewax1, viewax2)))
+ else
+ @test_throws "Parent's strides" strides(reinterpret(reshape, Int64, view(A, 1:2, viewax1, viewax2)))
+ end
+ @test_throws "Parent must" strides(reinterpret(reshape, Int64, view(A, 1:2:3, viewax1, viewax2)))
+ end
 end
 
 @testset "strides" begin