Added tests for Base.copy!

stdlib/Future/test/runtests.jl

@@ -1,4 +1 @@
 # This file is a part of Julia. License is MIT: https://julialang.org/license
-
-using Test
-using Future

test/copy.jl

@@ -1,7 +1,6 @@
 # This file is a part of Julia. License is MIT: https://julialang.org/license
 
 using Random
-
 mainres = ([4, 5, 3],
            [1, 5, 3])
 bitres = ([true, true, false],
@@ -268,3 +267,31 @@ end
     @test islocked(a.lock)
     @test !islocked(b.lock)
 end
+
+"""
+    Basic tests for Base.copy!
+"""
+
+using Test
+using Future
+
+@testset "Testing copy! for sets" begin
+    dst = Set([])  # Create an empty set
+    src = Set([1, 24, 5, 6, 51, 62])
+    copy!(dst, src)
+    @test dst == src
+end
+
+@testset "Testing copy! for Dictionaries" begin
+    dst = Dict("a" => 1, "b" => 2)
+    src = Dict("c" => 3, "d" => 4)
+    copy!(dst, src)
+    @test dst == src
+end
+
+@testset "Testing copy! for Arrays" begin
+    dst = [1, 2, 3]
+    src = [4, 5, 6]
+    copy!(dst, src)
+    @test dst == src
+end