From c332e901869d6c5f9c212d3a5670b59f32609683 Mon Sep 17 00:00:00 2001
From: Jishnu Bhattacharya <jishnub.github@gmail.com>
Date: Mon, 17 Jul 2023 16:40:02 +0530
Subject: [PATCH 1/2] Array(::AbstractRange) should return an Array

---
 base/range.jl  | 12 ++++++++++--
 test/ranges.jl | 20 ++++++++++++++++++++
 2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/base/range.jl b/base/range.jl
index 9f5dd214d67bb..d350e23954d5f 100644
--- a/base/range.jl
+++ b/base/range.jl
@@ -1377,8 +1377,16 @@ function vcat(rs::AbstractRange{T}...) where T
     return a
 end
 
-Array{T,1}(r::AbstractRange{T}) where {T} = vcat(r)
-collect(r::AbstractRange) = vcat(r)
+function Array{T,1}(r::AbstractRange{T}) where {T}
+    a = Vector{T}(undef, length(r))
+    i = 1
+    for x in r
+        @inbounds a[i] = x
+        i += 1
+    end
+    return a
+end
+collect(r::AbstractRange) = Array(r)
 
 _reverse(r::OrdinalRange, ::Colon) = (:)(last(r), negate(step(r)), first(r))
 function _reverse(r::StepRangeLen, ::Colon)
diff --git a/test/ranges.jl b/test/ranges.jl
index 0e195f5dde24e..c9bbdce70e904 100644
--- a/test/ranges.jl
+++ b/test/ranges.jl
@@ -1802,6 +1802,7 @@ Base.div(x::Displacement, y::Displacement) = Displacement(div(x.val, y.val))
 # required for collect (summing lengths); alternatively, should length return Int by default?
 Base.promote_rule(::Type{Displacement}, ::Type{Int}) = Int
 Base.convert(::Type{Int}, x::Displacement) = x.val
+Base.Int(x::Displacement) = x.val
 
 # Unsigned complement, for testing checked_length
 struct UPosition <: Unsigned
@@ -2498,3 +2499,22 @@ end
     # a case that using mul_with_overflow & add_with_overflow might get wrong:
     @test (-10:2:typemax(Int))[typemax(Int)÷2+2] == typemax(Int)-9
 end
+
+@testset "collect with specialized vcat" begin
+    struct OneToThree <: AbstractUnitRange{Int} end
+    Base.size(r::OneToThree) = (3,)
+    Base.first(r::OneToThree) = 1
+    Base.length(r::OneToThree) = 3
+    Base.last(r::OneToThree) = 3
+    function Base.getindex(r::OneToThree, i::Int)
+        checkbounds(r, i)
+        i
+    end
+    Base.vcat(r::OneToThree) = r
+    r = OneToThree()
+    a = Array(r)
+    @test a isa Vector{Int}
+    @test a == r
+    @test collect(r) isa Vector{Int}
+    @test collect(r) == r
+end

From 1b7bf936febef3c7a022c8a837b60963c217df9c Mon Sep 17 00:00:00 2001
From: Jishnu Bhattacharya <jishnub.github@gmail.com>
Date: Thu, 20 Jul 2023 13:15:20 +0530
Subject: [PATCH 2/2] Add comment to Array method

---
 base/range.jl | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/base/range.jl b/base/range.jl
index 635f921b5c1bd..e8ffe10e2ba7f 100644
--- a/base/range.jl
+++ b/base/range.jl
@@ -1380,6 +1380,11 @@ function vcat(rs::AbstractRange{T}...) where T
     return a
 end
 
+# This method differs from that for AbstractArrays as it
+# use iteration instead of indexing. This works even if certain
+# non-standard ranges don't support indexing.
+# See https://github.com/JuliaLang/julia/pull/27302
+# Similarly, collect(r::AbstractRange) uses iteration
 function Array{T,1}(r::AbstractRange{T}) where {T}
     a = Vector{T}(undef, length(r))
     i = 1