From e8a1c5db385e6524a2e292ecbcef6344d60fcd53 Mon Sep 17 00:00:00 2001
From: Katharine Hyatt <kslimes@gmail.com>
Date: Fri, 27 Feb 2026 14:49:32 +0100
Subject: [PATCH 1/3] Create JLArrays extension and tests for GPU mocking

---
 Project.toml              |  9 ++++++++-
 ext/StridedJLArraysExt.jl | 16 ++++++++++++++++
 test/jlarrays.jl          | 14 ++++++++++++++
 test/runtests.jl          |  3 ++-
 4 files changed, 40 insertions(+), 2 deletions(-)
 create mode 100644 ext/StridedJLArraysExt.jl
 create mode 100644 test/jlarrays.jl

diff --git a/Project.toml b/Project.toml
index 55aca8e..fa8770f 100644
--- a/Project.toml
+++ b/Project.toml
@@ -10,11 +10,13 @@ TupleTools = "9d95972d-f1c8-5527-a6e0-b4b365fa01f6"
 
 [weakdeps]
 AMDGPU = "21141c5a-9bdb-4563-92ae-f87d6854732e"
+JLArrays = "27aeb0d3-9eb9-45fb-866b-73c2ecf80fcb"
 GPUArrays = "0c68f7d7-f131-5f86-a1c3-88cf8149b2d7"
 CUDA = "052768ef-5323-5732-b1bb-66c8b64840ba"
 
 [extensions]
 StridedAMDGPUExt = "AMDGPU"
+StridedJLArraysExt = "JLArrays"
 StridedGPUArraysExt = "GPUArrays"
 StridedCUDAExt = "CUDA"
 
@@ -22,6 +24,7 @@ StridedCUDAExt = "CUDA"
 AMDGPU = "2"
 Aqua = "0.8"
 CUDA = "5"
+JLArrays = "0.3.1"
 GPUArrays = "11.4.1"
 LinearAlgebra = "1.6"
 Random = "1.6"
@@ -34,9 +37,13 @@ julia = "1.6"
 AMDGPU = "21141c5a-9bdb-4563-92ae-f87d6854732e"
 Aqua = "4c88cf16-eb10-579e-8560-4a9242c79595"
 CUDA = "052768ef-5323-5732-b1bb-66c8b64840ba"
+JLArrays = "27aeb0d3-9eb9-45fb-866b-73c2ecf80fcb"
 GPUArrays = "0c68f7d7-f131-5f86-a1c3-88cf8149b2d7"
 Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [targets]
-test = ["Test", "Random", "Aqua", "AMDGPU", "CUDA", "GPUArrays"]
+test = ["Test", "Random", "Aqua", "AMDGPU", "CUDA", "GPUArrays", "JLArrays"]
+
+[sources]
+StridedViews = {url = "https://github.com/QuantumKitHub/StridedViews.jl", rev = "ksh/jlarrays"}
diff --git a/ext/StridedJLArraysExt.jl b/ext/StridedJLArraysExt.jl
new file mode 100644
index 0000000..9ab5b3f
--- /dev/null
+++ b/ext/StridedJLArraysExt.jl
@@ -0,0 +1,16 @@
+module StridedJLArraysExt
+
+using Strided, StridedViews, JLArrays
+using JLArrays: Adapt
+using JLArrays: GPUArrays
+
+const ALL_FS = Union{typeof(adjoint), typeof(conj), typeof(identity), typeof(transpose)}
+
+function Base.copy!(dst::StridedView{TD, ND, TAD, FD}, src::StridedView{TS, NS, TAS, FS}) where {TD <: Number, ND, TAD <: JLArray{TD}, FD <: ALL_FS, TS <: Number, NS, TAS <: JLArray{TS}, FS <: ALL_FS}
+    bc_style = Base.Broadcast.BroadcastStyle(TAS)
+    bc = Base.Broadcast.Broadcasted(bc_style, identity, (src,), axes(dst))
+    GPUArrays._copyto!(dst, bc)
+    return dst
+end
+
+end
diff --git a/test/jlarrays.jl b/test/jlarrays.jl
new file mode 100644
index 0000000..9848347
--- /dev/null
+++ b/test/jlarrays.jl
@@ -0,0 +1,14 @@
+for T in (Float32, Float64, Complex{Float32}, Complex{Float64})
+    @testset "Copy with JLArrayStridedView: $T, $f1, $f2" for f2 in (identity, conj, adjoint, transpose), f1 in (identity, conj, transpose, adjoint)
+        for m1 in (0, 16, 32), m2 in (0, 16, 32)
+            A1 = JLArray(randn(T, (m1, m2)))
+            A2 = similar(A1)
+            A1c = copy(A1)
+            A2c = copy(A2)
+            B1 = f1(StridedView(A1c))
+            B2 = f2(StridedView(A2c))
+            axes(f1(A1)) == axes(f2(A2)) || continue
+            @test collect(Matrix(copy!(f2(A2), f1(A1)))) == JLArrays.Adapt.adapt(Vector{T}, copy!(B2, B1))
+        end
+    end
+end
diff --git a/test/runtests.jl b/test/runtests.jl
index 3f9ee6f..0b0dcc8 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -4,7 +4,7 @@ using Random
 using Strided
 using Strided: StridedView
 using Aqua
-using AMDGPU, CUDA, GPUArrays
+using JLArrays, AMDGPU, CUDA, GPUArrays
 
 Random.seed!(1234)
 
@@ -28,6 +28,7 @@ if !is_buildkite
     include("blasmultests.jl")
     Strided.disable_threaded_mul()
 
+    include("jlarrays.jl")
     Aqua.test_all(Strided; piracies = false)
 end
 

From a9224516bfddeac31326b48ad18788e25a30491d Mon Sep 17 00:00:00 2001
From: Katharine Hyatt <khyatt@flatironinstitute.org>
Date: Sat, 28 Feb 2026 03:14:14 -0500
Subject: [PATCH 2/3] No sources

---
 Project.toml | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/Project.toml b/Project.toml
index fa8770f..3472e21 100644
--- a/Project.toml
+++ b/Project.toml
@@ -44,6 +44,3 @@ Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [targets]
 test = ["Test", "Random", "Aqua", "AMDGPU", "CUDA", "GPUArrays", "JLArrays"]
-
-[sources]
-StridedViews = {url = "https://github.com/QuantumKitHub/StridedViews.jl", rev = "ksh/jlarrays"}

From 5c824e173a53dc82c0a4e50ff71df8e72103b8d0 Mon Sep 17 00:00:00 2001
From: Katharine Hyatt <khyatt@flatironinstitute.org>
Date: Mon, 2 Mar 2026 09:14:07 -0500
Subject: [PATCH 3/3] Add an AbstractArray option too

---
 ext/StridedJLArraysExt.jl | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/ext/StridedJLArraysExt.jl b/ext/StridedJLArraysExt.jl
index 9ab5b3f..1ea05b5 100644
--- a/ext/StridedJLArraysExt.jl
+++ b/ext/StridedJLArraysExt.jl
@@ -13,4 +13,11 @@ function Base.copy!(dst::StridedView{TD, ND, TAD, FD}, src::StridedView{TS, NS,
     return dst
 end
 
+function Base.copy!(dst::AbstractArray{TD, ND}, src::StridedView{TS, NS, TAS, FS}) where {TD <: Number, ND, TS <: Number, NS, TAS <: JLArray{TS}, FS <: ALL_FS}
+    bc_style = Base.Broadcast.BroadcastStyle(TAS)
+    bc = Base.Broadcast.Broadcasted(bc_style, identity, (src,), axes(dst))
+    GPUArrays._copyto!(dst, bc)
+    return dst
+end
+
 end