test simplifications and comments

Author: Christopher Rowley

test/JlWrap.jl

@@ -506,23 +506,26 @@ end
                 (InlineTimeDelta64{MINUTES}, "timedelta64[m]"),
                 (InlineTimeDelta64{(SECONDS, 5)}, "timedelta64[5s]"),
                 (InlineTimeDelta64{NumpyDates.UNBOUND_UNITS}, "timedelta64"),
-                (Tuple{}, np.dtype(pylist())),
-                (Tuple{Int32, Int32}, np.dtype(pylist([("f0", "int32"), ("f1", "int32")]))),
-                (@NamedTuple{}, np.dtype(pylist())),
-                (@NamedTuple{x::Int32, y::Int32}, np.dtype(pylist([("x", "int32"), ("y", "int32")]))),
-                (Pair{Int32, Int32}, np.dtype(pylist([("first", "int32"), ("second", "int32")]))),
+                (Tuple{}, pylist()),
+                (Tuple{Int32, Int32}, pylist([("f0", "int32"), ("f1", "int32")])),
+                (@NamedTuple{}, pylist()),
+                (@NamedTuple{x::Int32, y::Int32}, pylist([("x", "int32"), ("y", "int32")])),
+                (Pair{Int32, Int32}, pylist([("first", "int32"), ("second", "int32")])),
             ]
                 @test pyeq(Bool, pygetattr(pyjl(t), "__numpy_dtype__"), np.dtype(d))
                 @test pyeq(Bool, np.dtype(pyjl(t)), np.dtype(d))
             end
 
             # unsupported cases
             @testset "$t -> AttributeError" for t in [
+                # non-primitives or mutables
                 String,
                 Vector{Int},
+                # pointers
                 Ptr{Cvoid},
                 Ptr{Int},
-                Ptr{PythonCall.C.PyPtr},
+                # PyPtr specifically should NOT be interpreted as np.dtype("O")
+                PythonCall.C.PyPtr,
             ]
                 err = try
                     pygetattr(pyjl(t), "__numpy_dtype__")