support reshaping by ranges

Author: Pietro Vertechi

src/structarray.jl

@@ -188,3 +188,9 @@ Base.copy(s::StructArray{T,N,C}) where {T,N,C} = StructArray{T,N,C}(C(copy(x) fo
 function Base.reshape(s::StructArray{T}, d::Dims) where {T}
     StructArray{T}(map(x -> reshape(x, d), fieldarrays(s)))
 end
+
+for typ in [:Integer, :(Base.OneTo), :UnitRange, :(Base.IdentityUnitRange)]
+    @eval function Base.reshape(s::StructArray{T}, d::Tuple{$typ, Vararg{$typ}}) where {T}
+        StructArray{T}(map(x -> reshape(x, d), fieldarrays(s)))
+    end
+end

test/REQUIRE

@@ -1,2 +1,3 @@
 Tables
 WeakRefStrings
+OffsetArrays

test/runtests.jl

@@ -1,4 +1,5 @@
 using StructArrays
+using OffsetArrays: OffsetArray
 import Tables, PooledArrays, WeakRefStrings
 using Test
 
@@ -459,6 +460,30 @@ end
     @test v.b == [j for i in 1:3, j in 1:4]
 end
 
+@testset "collectoffset" begin
+    s = OffsetArray([(a=1,) for i in 1:10], -3)
+    sa = StructArray(s)
+    @test sa isa StructArray
+    @test axes(sa) == (-2:7,)
+    @test sa.a == fill(1, -2:7)
+
+    sa = StructArray(i for i in s)
+    @test sa isa StructArray
+    @test axes(sa) == (-2:7,)
+    @test sa.a == fill(1, -2:7)
+end
+
+@testset "reshape" begin
+    s = StructArray(a=[1,2,3,4], b=["a","b","c","d"])
+    rs = reshape(s, (2, 2))
+    @test rs.a == [1 3; 2 4]
+    @test rs.b == ["a" "c"; "b" "d"]
+
+    os = reshape(s, -1:2)
+    @test os.a == OffsetArray([1,2,3,4], -2)
+    @test os.b == OffsetArray(["a","b","c","d"], -2)
+end
+
 @testset "lazy" begin
     s = StructArray(rand(ComplexF64, 10, 10))
     rows = LazyRows(s)