From b7d75d0e988ca7163eab341c2c0f856266e1190e Mon Sep 17 00:00:00 2001
From: Aaron Kaw <aaronjkaw@gmail.com>
Date: Wed, 4 Sep 2024 08:50:34 +1000
Subject: [PATCH] Added tests to check if function inputs to derivative behave
 as expected

---
 test/diff.jl | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/test/diff.jl b/test/diff.jl
index 88956f138..23d9e837f 100644
--- a/test/diff.jl
+++ b/test/diff.jl
@@ -378,4 +378,15 @@ let
     Dt = Differential(t)^0
     @test isequal(Dt, identity)
     test_equal(Dt(t + 2t^2), t + 2t^2)
-end
\ No newline at end of file
+end
+
+# Check `Function` inputs for derivative (#1085)
+let
+    @variables x
+    @testset for f in [sqrt, sin, acos, exp, cis]
+        @test isequal(
+            Symbolics.derivative(f, x),
+            Symbolics.derivative(f(x), x)
+        )
+    end
+end