From b5fc7c88d653bc17431df20e230272c9f72d4eea Mon Sep 17 00:00:00 2001
From: Julia Sloan <jsloan@caltech.edu>
Date: Tue, 14 Jan 2025 11:18:09 -0800
Subject: [PATCH] add Field sum reproducer

---
 test/Fields/sum_repro.jl | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)
 create mode 100644 test/Fields/sum_repro.jl

diff --git a/test/Fields/sum_repro.jl b/test/Fields/sum_repro.jl
new file mode 100644
index 0000000000..75a7c8e566
--- /dev/null
+++ b/test/Fields/sum_repro.jl
@@ -0,0 +1,24 @@
+import ClimaComms
+ClimaComms.@import_required_backends
+import ClimaCore
+import ClimaCore: Fields
+using Test
+
+include(
+    joinpath(pkgdir(ClimaCore), "test", "TestUtilities", "TestUtilities.jl"),
+)
+import .TestUtilities as TU
+
+@testset "Sum function over field" begin
+    FT = Float32
+    context = ClimaComms.context()
+
+    space = TU.SpectralElementSpace2D(FT; context)
+    field = Fields.zeros(space)
+    f = x -> x + 1
+
+    # Sum of a function applied to a field should be the same as the sum of the
+    # function applied to the parent field, but it isn't
+    @test sum(f, field) != sum(f, parent(field))
+    @test sum(f.(field)) != sum(f.(parent(field)))
+end