From 36f5f274a572810891314aa4265833e82aa40d78 Mon Sep 17 00:00:00 2001
From: JohnnyChen <johnnychen94@hotmail.com>
Date: Tue, 9 Oct 2018 01:53:32 +0800
Subject: [PATCH 1/4] Support copy(::TrackedArray)

1. fix issue https://github.com/FluxML/Flux.jl/issues/416
2. change test code to pass the test: some broken tests are not broken now...
---
 src/tracker/scalar.jl | 2 ++
 test/tracker.jl       | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/tracker/scalar.jl b/src/tracker/scalar.jl
index 1b6098fb..ad7b643d 100644
--- a/src/tracker/scalar.jl
+++ b/src/tracker/scalar.jl
@@ -23,6 +23,8 @@ end
 
 Base.decompose(x::TrackedReal) = Base.decompose(data(x))
 
+Base.convert(::Type{T}, x::TrackedReal{S}) where {T<:Real,S} = convert(T, data(x))
+
 Base.convert(::Type{TrackedReal{T}}, x::TrackedReal{T}) where T = x
 
 Base.convert(::Type{TrackedReal{T}}, x::Real) where T = TrackedReal(convert(T, x))
diff --git a/test/tracker.jl b/test/tracker.jl
index a4772f2e..7d7168ad 100644
--- a/test/tracker.jl
+++ b/test/tracker.jl
@@ -40,7 +40,7 @@ function promotiontest(f, A, B, C)
   if all(ndims.((A,B,C)) .≤ 2) && f ∈ [hcat, vcat]
     r3 = f(A, B, param(C))
   else
-    @test_throws MethodError f(A, B, param(C)) # until julia#20815 is resolved
+    @test_broken f(A, B, param(C)) # until julia#20815 is resolved
     r3 = r2
   end
   r4 = f(param(A), param(B), param(C))

From 27fec15fcc5fc9af64edf533377f206f2be06443 Mon Sep 17 00:00:00 2001
From: JohnnyChen <johnnychen94@hotmail.com>
Date: Tue, 9 Oct 2018 03:34:41 +0800
Subject: [PATCH 2/4] Add explicit copy(x::TrackedArray) method

---
 src/tracker/array.jl  | 2 ++
 src/tracker/scalar.jl | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/src/tracker/array.jl b/src/tracker/array.jl
index 3d9836d0..b8b06471 100644
--- a/src/tracker/array.jl
+++ b/src/tracker/array.jl
@@ -43,6 +43,8 @@ end
 
 Base.print_array(io::IO, x::TrackedArray) = Base.print_array(io, data(x))
 
+Base.copy(x::TrackedArray) = copy(data(x))
+
 Base.setindex!(xs::TrackedArray, v, i...) =
   error("Can't differentiate `setindex!`")
 
diff --git a/src/tracker/scalar.jl b/src/tracker/scalar.jl
index ad7b643d..e0ae7db1 100644
--- a/src/tracker/scalar.jl
+++ b/src/tracker/scalar.jl
@@ -23,6 +23,8 @@ end
 
 Base.decompose(x::TrackedReal) = Base.decompose(data(x))
 
+Base.copy(x::TrackedArray) = copy(data(x))
+
 Base.convert(::Type{T}, x::TrackedReal{S}) where {T<:Real,S} = convert(T, data(x))
 
 Base.convert(::Type{TrackedReal{T}}, x::TrackedReal{T}) where T = x

From eaacec852fe6a78f7d77bc38e755e1c7c5b1a0d9 Mon Sep 17 00:00:00 2001
From: JohnnyChen <johnnychen94@hotmail.com>
Date: Tue, 9 Oct 2018 03:40:02 +0800
Subject: [PATCH 3/4] Bug fix

---
 src/tracker/scalar.jl | 2 +-
 test/tracker.jl       | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/tracker/scalar.jl b/src/tracker/scalar.jl
index e0ae7db1..ba83d937 100644
--- a/src/tracker/scalar.jl
+++ b/src/tracker/scalar.jl
@@ -23,7 +23,7 @@ end
 
 Base.decompose(x::TrackedReal) = Base.decompose(data(x))
 
-Base.copy(x::TrackedArray) = copy(data(x))
+Base.copy(x::TrackedReal) = copy(data(x))
 
 Base.convert(::Type{T}, x::TrackedReal{S}) where {T<:Real,S} = convert(T, data(x))
 
diff --git a/test/tracker.jl b/test/tracker.jl
index 7d7168ad..a4772f2e 100644
--- a/test/tracker.jl
+++ b/test/tracker.jl
@@ -40,7 +40,7 @@ function promotiontest(f, A, B, C)
   if all(ndims.((A,B,C)) .≤ 2) && f ∈ [hcat, vcat]
     r3 = f(A, B, param(C))
   else
-    @test_broken f(A, B, param(C)) # until julia#20815 is resolved
+    @test_throws MethodError f(A, B, param(C)) # until julia#20815 is resolved
     r3 = r2
   end
   r4 = f(param(A), param(B), param(C))

From de7623ac94a81f47048e5ee149eb5fd449d2cdc5 Mon Sep 17 00:00:00 2001
From: JohnnyChen <johnnychen94@hotmail.com>
Date: Tue, 9 Oct 2018 03:49:17 +0800
Subject: [PATCH 4/4] use variable assignment to do "copy"

---
 src/tracker/array.jl  | 2 +-
 src/tracker/scalar.jl | 4 +---
 2 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/src/tracker/array.jl b/src/tracker/array.jl
index b8b06471..00fe4cc4 100644
--- a/src/tracker/array.jl
+++ b/src/tracker/array.jl
@@ -43,7 +43,7 @@ end
 
 Base.print_array(io::IO, x::TrackedArray) = Base.print_array(io, data(x))
 
-Base.copy(x::TrackedArray) = copy(data(x))
+Base.copy(x::TrackedArray) = x
 
 Base.setindex!(xs::TrackedArray, v, i...) =
   error("Can't differentiate `setindex!`")
diff --git a/src/tracker/scalar.jl b/src/tracker/scalar.jl
index ba83d937..e37ee843 100644
--- a/src/tracker/scalar.jl
+++ b/src/tracker/scalar.jl
@@ -23,9 +23,7 @@ end
 
 Base.decompose(x::TrackedReal) = Base.decompose(data(x))
 
-Base.copy(x::TrackedReal) = copy(data(x))
-
-Base.convert(::Type{T}, x::TrackedReal{S}) where {T<:Real,S} = convert(T, data(x))
+Base.copy(x::TrackedReal) = x
 
 Base.convert(::Type{TrackedReal{T}}, x::TrackedReal{T}) where T = x