Datetime widget fixes

docs/source/examples/Widget List.ipynb

@@ -1157,6 +1157,28 @@
     ")"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Naive picker\n",
+    "\n",
+    "In some cases you might want to be able to pick naive datetime objects, i.e. timezone-unaware datetimes. To quote the Python 3 docs:\n",
+    "\n",
+    "> Naive objects are easy to understand and to work with, at the cost of ignoring some aspects of reality.\n",
+    "\n",
+    "This is useful if you need to compare the picked datetime to naive datetime objects, as Python will otherwise complain!"
+   ]
+   },
+   {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "ipywidgets.NaiveDatetimePicker(description='Pick a Time')"
+   ]
+  },
   {
    "cell_type": "markdown",
    "metadata": {},

python/ipywidgets/ipywidgets/widgets/__init__.py

@@ -15,7 +15,7 @@
 from .widget_int import IntText, BoundedIntText, IntSlider, IntProgress, IntRangeSlider, Play, SliderStyle
 from .widget_color import ColorPicker
 from .widget_date import DatePicker
-from .widget_datetime import DatetimePicker
+from .widget_datetime import DatetimePicker, NaiveDatetimePicker
 from .widget_time import TimePicker
 from .widget_output import Output
 from .widget_selection import RadioButtons, ToggleButtons, ToggleButtonsStyle, Dropdown, Select, SelectionSlider, SelectMultiple, SelectionRangeSlider

python/ipywidgets/ipywidgets/widgets/tests/test_widget_datetime.py

@@ -6,106 +6,152 @@
 
 import pytest
 
+from contextlib import nullcontext
 import datetime
+import itertools
 
 import pytz
 from traitlets import TraitError
 
 from ..widget_datetime import DatetimePicker
 
 
+dt_1442 = datetime.datetime(1442, 1, 1, tzinfo=pytz.utc)
+dt_1664 = datetime.datetime(1664, 1, 1, tzinfo=pytz.utc)
+dt_1994 = datetime.datetime(1994, 1, 1, tzinfo=pytz.utc)
+dt_2002 = datetime.datetime(2002, 2, 20, 13, 37, 42, 7, tzinfo=pytz.utc)
+dt_2056 = datetime.datetime(2056, 1, 1, tzinfo=pytz.utc)
+
 def test_time_creation_blank():
     w = DatetimePicker()
     assert w.value is None
 
 
 def test_time_creation_value():
-    t = datetime.datetime.now(pytz.utc)
-    w = DatetimePicker(value=t)
-    assert w.value is t
+    dt = datetime.datetime.now(pytz.utc)
+    w = DatetimePicker(value=dt)
+    assert w.value is dt
 
 
-def test_time_validate_value_none():
-    t = datetime.datetime(2002, 2, 20, 13, 37, 42, 7, tzinfo=pytz.utc)
-    t_min = datetime.datetime(1442, 1, 1, tzinfo=pytz.utc)
-    t_max = datetime.datetime(2056, 1, 1, tzinfo=pytz.utc)
-    w = DatetimePicker(value=t, min=t_min, max=t_max)
+def test_datetime_validate_value_none():
+    dt = dt_2002
+    dt_min = dt_1442
+    dt_max = dt_2056
+    w = DatetimePicker(value=dt, min=dt_min, max=dt_max)
     w.value = None
     assert w.value is None
 
 
-def test_time_validate_value_vs_min():
-    t = datetime.datetime(2002, 2, 20, 13, 37, 42, 7, tzinfo=pytz.utc)
-    t_min = datetime.datetime(2019, 1, 1, tzinfo=pytz.utc)
-    t_max = datetime.datetime(2056, 1, 1, tzinfo=pytz.utc)
-    w = DatetimePicker(min=t_min, max=t_max)
-    w.value = t
+def _permuted_dts():
+    ret = []
+    combos = list(itertools.product([None, dt_1442, dt_2002, dt_2056], repeat=3))
+    for vals in combos:
+        expected = vals[0]
+        if vals[1] and vals[2] and vals[1] > vals[2]:
+            expected = TraitError
+        elif vals[0] is None:
+            pass
+        elif vals[1] and vals[1] > vals[0]:
+            expected = vals[1]
+        elif vals[2] and vals[2] < vals[0]:
+            expected = vals[2]
+        ret.append(vals + (expected,))
+    return ret
+
+
+@pytest.mark.parametrize(
+    "input_value,input_min,input_max,expected",
+    _permuted_dts()
+)
+def test_datetime_cross_validate_value_min_max(
+    input_value,
+    input_min,
+    input_max,
+    expected,
+):
+    w = DatetimePicker(value=dt_2002, min=dt_2002, max=dt_2002)
+    should_raise = expected is TraitError
+    with pytest.raises(expected) if should_raise else nullcontext():
+        with w.hold_trait_notifications():
+            w.value = input_value
+            w.min = input_min
+            w.max = input_max
+    if not should_raise:
+        assert w.value is expected
+
+
+def test_datetime_validate_value_vs_min():
+    dt = dt_2002
+    dt_min = datetime.datetime(2019, 1, 1, tzinfo=pytz.utc)
+    dt_max = dt_2056
+    w = DatetimePicker(min=dt_min, max=dt_max)
+    w.value = dt
     assert w.value.year == 2019
 
 
-def test_time_validate_value_vs_max():
-    t = datetime.datetime(2002, 2, 20, 13, 37, 42, 7, tzinfo=pytz.utc)
-    t_min = datetime.datetime(1664, 1, 1, tzinfo=pytz.utc)
-    t_max = datetime.datetime(1994, 1, 1, tzinfo=pytz.utc)
-    w = DatetimePicker(min=t_min, max=t_max)
-    w.value = t
+def test_datetime_validate_value_vs_max():
+    dt = dt_2002
+    dt_min = dt_1664
+    dt_max = dt_1994
+    w = DatetimePicker(min=dt_min, max=dt_max)
+    w.value = dt
     assert w.value.year == 1994
 
 
-def test_time_validate_min_vs_value():
-    t = datetime.datetime(2002, 2, 20, 13, 37, 42, 7, tzinfo=pytz.utc)
-    t_min = datetime.datetime(2019, 1, 1, tzinfo=pytz.utc)
-    t_max = datetime.datetime(2056, 1, 1, tzinfo=pytz.utc)
-    w = DatetimePicker(value=t, max=t_max)
-    w.min = t_min
+def test_datetime_validate_min_vs_value():
+    dt = dt_2002
+    dt_min = datetime.datetime(2019, 1, 1, tzinfo=pytz.utc)
+    dt_max = dt_2056
+    w = DatetimePicker(value=dt, max=dt_max)
+    w.min = dt_min
     assert w.value.year == 2019
 
 
-def test_time_validate_min_vs_max():
-    t = datetime.datetime(2002, 2, 20, 13, 37, 42, 7, tzinfo=pytz.utc)
-    t_min = datetime.datetime(2112, 1, 1, tzinfo=pytz.utc)
-    t_max = datetime.datetime(2056, 1, 1, tzinfo=pytz.utc)
-    w = DatetimePicker(value=t, max=t_max)
+def test_datetime_validate_min_vs_max():
+    dt = dt_2002
+    dt_min = datetime.datetime(2112, 1, 1, tzinfo=pytz.utc)
+    dt_max = dt_2056
+    w = DatetimePicker(value=dt, max=dt_max)
     with pytest.raises(TraitError):
-        w.min = t_min
+        w.min = dt_min
 
 
-def test_time_validate_max_vs_value():
-    t = datetime.datetime(2002, 2, 20, 13, 37, 42, 7, tzinfo=pytz.utc)
-    t_min = datetime.datetime(1664, 1, 1, tzinfo=pytz.utc)
-    t_max = datetime.datetime(1994, 1, 1, tzinfo=pytz.utc)
-    w = DatetimePicker(value=t, min=t_min)
-    w.max = t_max
+def test_datetime_validate_max_vs_value():
+    dt = dt_2002
+    dt_min = dt_1664
+    dt_max = dt_1994
+    w = DatetimePicker(value=dt, min=dt_min)
+    w.max = dt_max
     assert w.value.year == 1994
 
 
-def test_time_validate_max_vs_min():
-    t = datetime.datetime(2002, 2, 20, 13, 37, 42, 7, tzinfo=pytz.utc)
-    t_min = datetime.datetime(1664, 1, 1, tzinfo=pytz.utc)
-    t_max = datetime.datetime(1337, 1, 1, tzinfo=pytz.utc)
-    w = DatetimePicker(value=t, min=t_min)
+def test_datetime_validate_max_vs_min():
+    dt = dt_2002
+    dt_min = dt_1664
+    dt_max = datetime.datetime(1337, 1, 1, tzinfo=pytz.utc)
+    w = DatetimePicker(value=dt, min=dt_min)
     with pytest.raises(TraitError):
-        w.max = t_max
+        w.max = dt_max
 
 
-def test_time_validate_naive():
-    t = datetime.datetime(2002, 2, 20, 13, 37, 42, 7, tzinfo=pytz.utc)
-    t_min = datetime.datetime(1442, 1, 1, tzinfo=pytz.utc)
-    t_max = datetime.datetime(2056, 1, 1, tzinfo=pytz.utc)
+def test_datetime_validate_naive():
+    dt = dt_2002
+    dt_min = dt_1442
+    dt_max = dt_2056
 
-    w = DatetimePicker(value=t, min=t_min, max=t_max)
+    w = DatetimePicker(value=dt, min=dt_min, max=dt_max)
     with pytest.raises(TraitError):
-        w.max = t_max.replace(tzinfo=None)
+        w.max = dt_max.replace(tzinfo=None)
     with pytest.raises(TraitError):
-        w.min = t_min.replace(tzinfo=None)
+        w.min = dt_min.replace(tzinfo=None)
     with pytest.raises(TraitError):
-        w.value = t.replace(tzinfo=None)
+        w.value = dt.replace(tzinfo=None)
 
 
 def test_datetime_tzinfo():
     tz = pytz.timezone('Australia/Sydney')
-    t = datetime.datetime(2002, 2, 20, 13, 37, 42, 7, tzinfo=tz)
-    w = DatetimePicker(value=t)
-    assert w.value == t
+    dt = datetime.datetime(2002, 2, 20, 13, 37, 42, 7, tzinfo=tz)
+    w = DatetimePicker(value=dt)
+    assert w.value == dt
     # tzinfo only changes upon input from user
     assert w.value.tzinfo == tz

python/ipywidgets/ipywidgets/widgets/tests/test_widget_time.py

@@ -24,6 +24,20 @@ def test_time_creation_value():
     assert w.value is t
 
 
+def test_time_cross_validate_value_min_max():
+    w = TimePicker(value=datetime.time(2), min=datetime.time(2), max=datetime.time(2))
+    with w.hold_trait_notifications():
+        w.value = None
+        w.min = datetime.time(4)
+        w.max = datetime.time(6)
+    assert w.value is None
+    with w.hold_trait_notifications():
+        w.value = datetime.time(4)
+        w.min = None
+        w.max = None
+    assert w.value == datetime.time(4)
+
+
 def test_time_validate_value_none():
     t = datetime.time(13, 37, 42, 7)
     t_min = datetime.time(2)

python/ipywidgets/ipywidgets/widgets/widget_date.py

@@ -54,6 +54,8 @@ class DatePicker(DescriptionWidget, ValueWidget, CoreWidget):
     def _validate_value(self, proposal):
         """Cap and floor value"""
         value = proposal["value"]
+        if value is None:
+            return value
         if self.min and self.min > value:
             value = max(value, self.min)
         if self.max and self.max < value:
@@ -64,6 +66,8 @@ def _validate_value(self, proposal):
     def _validate_min(self, proposal):
         """Enforce min <= value <= max"""
         min = proposal["value"]
+        if min is None:
+            return min
         if self.max and min > self.max:
             raise TraitError("Setting min > max")
         if self.value and min > self.value:
@@ -74,6 +78,8 @@ def _validate_min(self, proposal):
     def _validate_max(self, proposal):
         """Enforce min <= value <= max"""
         max = proposal["value"]
+        if max is None:
+            return max
         if self.min and max < self.min:
             raise TraitError("setting max < min")
         if self.value and max < self.value:

python/ipywidgets/ipywidgets/widgets/widget_datetime.py

@@ -61,6 +61,8 @@ def _validate_tz(self, value):
     def _validate_value(self, proposal):
         """Cap and floor value"""
         value = proposal["value"]
+        if value is None:
+            return value
         value = self._validate_tz(value)
         if self.min and self.min > value:
             value = max(value, self.min)
@@ -72,6 +74,8 @@ def _validate_value(self, proposal):
     def _validate_min(self, proposal):
         """Enforce min <= value <= max"""
         min = proposal["value"]
+        if min is None:
+            return min
         min = self._validate_tz(min)
         if self.max and min > self.max:
             raise TraitError("Setting min > max")
@@ -83,6 +87,8 @@ def _validate_min(self, proposal):
     def _validate_max(self, proposal):
         """Enforce min <= value <= max"""
         max = proposal["value"]
+        if max is None:
+            return max
         max = self._validate_tz(max)
         if self.min and max < self.min:
             raise TraitError("setting max < min")

python/ipywidgets/ipywidgets/widgets/widget_time.py

@@ -63,6 +63,8 @@ class TimePicker(DescriptionWidget, ValueWidget, CoreWidget):
     def _validate_value(self, proposal):
         """Cap and floor value"""
         value = proposal["value"]
+        if value is None:
+            return value
         if self.min and self.min > value:
             value = max(value, self.min)
         if self.max and self.max < value:
@@ -73,6 +75,8 @@ def _validate_value(self, proposal):
     def _validate_min(self, proposal):
         """Enforce min <= value <= max"""
         min = proposal["value"]
+        if min is None:
+            return min
         if self.max and min > self.max:
             raise TraitError("Setting min > max")
         if self.value and min > self.value:
@@ -83,6 +87,8 @@ def _validate_min(self, proposal):
     def _validate_max(self, proposal):
         """Enforce min <= value <= max"""
         max = proposal["value"]
+        if max is None:
+            return max
         if self.min and max < self.min:
             raise TraitError("setting max < min")
         if self.value and max < self.value: