tests

test/connection.jl

@@ -16,10 +16,28 @@ end
 @testset "Method error hints." begin
     nc = NATS.connect()
 
-    @test_throws MethodError subscribe("SOME.THING") do msg::Float64
+    hint = """To use `Type{Float64}` as parameter of subscription handler apropriate conversion from `Type{NATS.Msg}` must be provided.
+            ```
+            import Base: convert
+            
+            function convert(::Type{Type{Float64}}, msg::Union{NATS.Msg, NATS.HMsg})
+                # Implement conversion logic here.
+            end
+            """
+    @test_throws hint subscribe("SOME.THING") do msg::Float64
         put!(c, msg)
     end
     @test_throws MethodError request("SOME.REQUESTS"; payload = 4)
+    hint = """Object of type `Int64` cannot be serialized into payload."""
+    @test_throws hint request("SOME.REQUESTS", 4) # TODO: in this case there should be rather warning about missing payload.
+    hint = """To use `Type{Integer}` as parameter of subscription handler apropriate conversion from `Type{NATS.Msg}` must be provided.
+            ```
+            import Base: convert
+            
+            function convert(::Type{Type{Integer}}, msg::Union{NATS.Msg, NATS.HMsg})
+                # Implement conversion logic here.
+            end
+            """
     @test_throws MethodError reply("SOME.REQUESTS") do msg::Integer
         "Received $msg"
     end

test/reqreply.jl

@@ -26,6 +26,7 @@ end
         "Reply from service 2."
     end
     results = request(subject, "This is request payload", 2)
+    sleep(1)
     unsubscribe(sub1)
     unsubscribe(sub2)
     sleep(0.1)