Change datetime constructors to use Rust Option

This makes it cleaner to call PyTime::new and PyDateTime::new from Rust
without needing to retrieve a Python None.

src/objects/datetime.rs

@@ -102,7 +102,7 @@ impl PyDateTime {
         minute: u32,
         second: u32,
         microsecond: u32,
-        tzinfo: &PyObject,
+        tzinfo: Option<&PyObject>,
     ) -> PyResult<Py<PyDateTime>> {
         unsafe {
             let ptr = PyDateTimeAPI.DateTime_FromDateAndTime.unwrap()(
@@ -113,7 +113,10 @@ impl PyDateTime {
                 minute as c_int,
                 second as c_int,
                 microsecond as c_int,
-                tzinfo.as_ptr(),
+                match tzinfo {
+                    Some(o) => o.as_ptr(),
+                    None => py.None().as_ptr(),
+                },
                 PyDateTimeAPI.DateTimeType,
             );
             Py::from_owned_ptr_or_err(py, ptr)
@@ -184,7 +187,7 @@ impl PyTime {
         minute: u32,
         second: u32,
         microsecond: u32,
-        tzinfo: &PyObject,
+        tzinfo: Option<&PyObject>,
     ) -> PyResult<Py<PyTime>> {
         unsafe {
             let ptr = PyDateTimeAPI.Time_FromTime.unwrap()(
@@ -192,7 +195,10 @@ impl PyTime {
                 minute as c_int,
                 second as c_int,
                 microsecond as c_int,
-                tzinfo.as_ptr(),
+                match tzinfo {
+                    Some(o) => o.as_ptr(),
+                    None => py.None().as_ptr(),
+                },
                 PyDateTimeAPI.TimeType,
             );
             Py::from_owned_ptr_or_err(py, ptr)
@@ -206,7 +212,7 @@ impl PyTime {
         minute: u32,
         second: u32,
         microsecond: u32,
-        tzinfo: &PyObject,
+        tzinfo: Option<&PyObject>,
         fold: bool,
     ) -> PyResult<Py<PyTime>> {
         unsafe {
@@ -215,7 +221,10 @@ impl PyTime {
                 minute as c_int,
                 second as c_int,
                 microsecond as c_int,
-                tzinfo.as_ptr(),
+                match tzinfo {
+                    Some(o) => o.as_ptr(),
+                    None => py.None().as_ptr(),
+                },
                 fold as c_int,
                 PyDateTimeAPI.TimeType,
             );

tests/rustapi_module/src/lib.rs

@@ -13,15 +13,6 @@ use pyo3::prelude::{PyDict, PyTuple};
 use pyo3::{ObjectProtocol, ToPyObject};
 use pyo3::{Py, PyResult, Python};
 
-macro_rules! to_pyobject {
-    ($py:expr, $o:ident) => {
-        match $o {
-            Some(t) => t.to_object($py),
-            None => $py.None(),
-        }
-    };
-}
-
 #[pyfunction]
 fn make_date(py: Python, year: u32, month: u32, day: u32) -> PyResult<Py<PyDate>> {
     PyDate::new(py, year, month, day)
@@ -48,8 +39,14 @@ fn make_time(
     microsecond: u32,
     tzinfo: Option<&PyTzInfo>,
 ) -> PyResult<Py<PyTime>> {
-    let tzi: PyObject = to_pyobject!(py, tzinfo);
-    PyTime::new(py, hour, minute, second, microsecond, &tzi)
+    PyTime::new(
+        py,
+        hour,
+        minute,
+        second,
+        microsecond,
+        tzinfo.map(|o| o.to_object(py)).as_ref(),
+    )
 }
 
 #[cfg(Py_3_6)]
@@ -63,8 +60,15 @@ fn time_with_fold(
     tzinfo: Option<&PyTzInfo>,
     fold: bool,
 ) -> PyResult<Py<PyTime>> {
-    let tzi = to_pyobject!(py, tzinfo);
-    PyTime::new_with_fold(py, hour, minute, second, microsecond, &tzi, fold)
+    PyTime::new_with_fold(
+        py,
+        hour,
+        minute,
+        second,
+        microsecond,
+        tzinfo.map(|o| o.to_object(py)).as_ref(),
+        fold,
+    )
 }
 
 #[pyfunction]
@@ -124,10 +128,6 @@ fn make_datetime(
     microsecond: u32,
     tzinfo: Option<&PyTzInfo>,
 ) -> PyResult<Py<PyDateTime>> {
-    let tzi: PyObject = match tzinfo {
-        Some(t) => t.to_object(py),
-        None => py.None(),
-    };
     PyDateTime::new(
         py,
         year,
@@ -137,7 +137,7 @@ fn make_datetime(
         minute,
         second,
         microsecond,
-        &tzi,
+        tzinfo.map(|o| (o.to_object(py))).as_ref(),
     )
 }
 

tests/test_datetime.rs

@@ -107,6 +107,29 @@ fn test_delta_check() {
     assert_check_only!(PyDelta_Check, sub_sub_obj);
 }
 
+#[test]
+#[cfg(Py_3)]
+fn test_datetime_utc() {
+    let gil = Python::acquire_gil();
+    let py = gil.python();
+
+    let datetime = py.import("datetime").map_err(|e| e.print(py)).unwrap();
+    let timezone = datetime.get("timezone").unwrap();
+    let utc = timezone.getattr("utc").unwrap().to_object(py);
+
+    let dt = PyDateTime::new(py, 2018, 1, 1, 0, 0, 0, 0, Some(&utc)).unwrap();
+
+    let locals = PyDict::new(py);
+    locals.set_item("dt", dt).unwrap();
+
+    let offset: f32 = py
+        .eval("dt.utcoffset().total_seconds()", None, Some(locals))
+        .unwrap()
+        .extract()
+        .unwrap();
+    assert_eq!(offset, 0f32);
+}
+
 #[cfg(Py_3_6)]
 #[test]
 fn test_pydate_out_of_bounds() {