From 267909caed1f93b3d832e51825f1524b34592d14 Mon Sep 17 00:00:00 2001
From: Aayush Sabharwal <aayush.sabharwal@juliahub.com>
Date: Thu, 11 Apr 2024 18:42:01 +0530
Subject: [PATCH] feat: support partial updates with remake_buffer

---
 src/remake.jl       | 3 ++-
 test/remake_test.jl | 8 ++++----
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/src/remake.jl b/src/remake.jl
index 2dbfe08..0eb06c3 100644
--- a/src/remake.jl
+++ b/src/remake.jl
@@ -11,7 +11,7 @@ returned buffer should be of the same type (ignoring type-parameters) as `oldbuf
 
 This method is already implemented for
 `remake_buffer(sys, oldbuffer::AbstractArray, vals::Dict)` and supports static arrays
-as well.
+as well. It is also implemented for `oldbuffer::Tuple`.
 """
 function remake_buffer(sys, oldbuffer::AbstractArray, vals::Dict)
     # similar when used with an `MArray` and nonconcrete eltype returns a
@@ -23,6 +23,7 @@ function remake_buffer(sys, oldbuffer::AbstractArray, vals::Dict)
         end
 
         newbuffer = similar(oldbuffer, elT)
+        copyto!(newbuffer, oldbuffer)
         setu(sys, collect(keys(vals)))(newbuffer, elT.(values(vals)))
     else
         mutbuffer = remake_buffer(sys, collect(oldbuffer), vals)
diff --git a/test/remake_test.jl b/test/remake_test.jl
index 9f4bad1..0618e2e 100644
--- a/test/remake_test.jl
+++ b/test/remake_test.jl
@@ -7,17 +7,17 @@ for (buf, newbuf, newvals) in [
     # standard operation
     ([1.0, 2.0, 3.0], [2.0, 3.0, 4.0], Dict(:x => 2.0, :y => 3.0, :z => 4.0)),
     # buffer type "demotion"
-    ([1.0, 2.0, 3.0], [2, 3, 4], Dict(:x => 2, :y => 3, :z => 4)),
+    ([1.0, 2.0, 3.0], [2, 2, 3], Dict(:x => 2)),
     # buffer type promotion
-    ([1, 2, 3], [2.0, 3.0, 4.0], Dict(:x => 2.0, :y => 3.0, :z => 4.0)),
+    ([1, 2, 3], [2.0, 2.0, 3.0], Dict(:x => 2.0)),
     # value type promotion
     ([1, 2, 3], [2.0, 3.0, 4.0], Dict(:x => 2, :y => 3.0, :z => 4.0)),
     # standard operation
     ([1.0, 2.0, 3.0], [2.0, 3.0, 4.0], Dict(:a => 2.0, :b => 3.0, :c => 4.0)),
     # buffer type "demotion"
-    ([1.0, 2.0, 3.0], [2, 3, 4], Dict(:a => 2, :b => 3, :c => 4)),
+    ([1.0, 2.0, 3.0], [2, 2, 3], Dict(:a => 2)),
     # buffer type promotion
-    ([1, 2, 3], [2.0, 3.0, 4.0], Dict(:a => 2.0, :b => 3.0, :c => 4.0)),
+    ([1, 2, 3], [2.0, 2.0, 3.0], Dict(:a => 2.0)),
     # value type promotion
     ([1, 2, 3], [2, 3.0, 4.0], Dict(:a => 2, :b => 3.0, :c => 4.0))
 ]