SplitDateTimeField: Consider field empty if only a time is given

src/pretix/base/forms/questions.py

@@ -16,6 +16,7 @@ from pretix.base.forms.widgets import (
 )
 from pretix.base.models import InvoiceAddress, Question
 from pretix.base.models.tax import EU_COUNTRIES
+from pretix.control.forms import SplitDateTimeField
 from pretix.helpers.i18n import get_format_without_seconds
 from pretix.presale.signals import question_form_fields
 
@@ -143,7 +144,7 @@ class BaseQuestionsForm(forms.Form):
                     widget=TimePickerWidget(time_format=get_format_without_seconds('TIME_INPUT_FORMATS')),
                 )
             elif q.type == Question.TYPE_DATETIME:
-                field = forms.SplitDateTimeField(
+                field = SplitDateTimeField(
                     label=q.question, required=q.required,
                     help_text=q.help_text,
                     initial=dateutil.parser.parse(initial.answer).astimezone(tz) if initial and initial.answer else None,

src/pretix/control/forms/__init__.py

@@ -1,7 +1,10 @@
+import datetime
 import os
 
 from django import forms
 from django.conf import settings
+from django.core.exceptions import ValidationError
+from django.forms.utils import from_current_timezone
 from django.utils.html import conditional_escape
 from django.utils.translation import ugettext_lazy as _
 
@@ -168,3 +171,17 @@ class SingleLanguageWidget(forms.Select):
     def optgroups(self, name, value, attrs=None):
         self.modify()
         return super().optgroups(name, value, attrs)
+
+
+class SplitDateTimeField(forms.SplitDateTimeField):
+
+    def compress(self, data_list):
+        # Differs from the default implementation: If only a time is given and no date, we consider the field empty
+        if data_list:
+            if data_list[0] in self.empty_values:
+                return None
+            if data_list[1] in self.empty_values:
+                raise ValidationError(self.error_messages['invalid_date'], code='invalid_date')
+            result = datetime.datetime.combine(*data_list)
+            return from_current_timezone(result)
+        return None

src/pretix/control/forms/event.py

@@ -22,7 +22,7 @@ from pretix.base.models.event import EventMetaValue, SubEvent
 from pretix.base.reldate import RelativeDateField, RelativeDateTimeField
 from pretix.control.forms import (
     ExtFileField, MultipleLanguagesWidget, SingleLanguageWidget, SlugWidget,
-    SplitDateTimePickerWidget,
+    SplitDateTimeField, SplitDateTimePickerWidget,
 )
 from pretix.multidomain.urlreverse import build_absolute_uri
 from pretix.plugins.banktransfer.payment import BankTransfer
@@ -95,10 +95,10 @@ class EventWizardBasicsForm(I18nModelForm):
             'location',
         ]
         field_classes = {
-            'date_from': forms.SplitDateTimeField,
+            'date_from': SplitDateTimeField,
-            'date_to': forms.SplitDateTimeField,
+            'date_to': SplitDateTimeField,
-            'presale_start': forms.SplitDateTimeField,
+            'presale_start': SplitDateTimeField,
-            'presale_end': forms.SplitDateTimeField,
+            'presale_end': SplitDateTimeField,
         }
         widgets = {
             'date_from': SplitDateTimePickerWidget(),
@@ -229,11 +229,11 @@ class EventUpdateForm(I18nModelForm):
             'location',
         ]
         field_classes = {
-            'date_from': forms.SplitDateTimeField,
+            'date_from': SplitDateTimeField,
-            'date_to': forms.SplitDateTimeField,
+            'date_to': SplitDateTimeField,
-            'date_admission': forms.SplitDateTimeField,
+            'date_admission': SplitDateTimeField,
-            'presale_start': forms.SplitDateTimeField,
+            'presale_start': SplitDateTimeField,
-            'presale_end': forms.SplitDateTimeField,
+            'presale_end': SplitDateTimeField,
         }
         widgets = {
             'date_from': SplitDateTimePickerWidget(),

src/pretix/control/forms/item.py

@@ -14,7 +14,7 @@ from pretix.base.models import (
 )
 from pretix.base.models.items import ItemAddOn
 from pretix.base.signals import item_copy_data
-from pretix.control.forms import SplitDateTimePickerWidget
+from pretix.control.forms import SplitDateTimeField, SplitDateTimePickerWidget
 from pretix.control.forms.widgets import Select2
 from pretix.helpers.models import modelcopy
 from pretix.helpers.money import change_decimal_field
@@ -330,8 +330,8 @@ class ItemUpdateForm(I18nModelForm):
             'original_price'
         ]
         field_classes = {
-            'available_from': forms.SplitDateTimeField,
+            'available_from': SplitDateTimeField,
-            'available_until': forms.SplitDateTimeField,
+            'available_until': SplitDateTimeField,
         }
         widgets = {
             'available_from': SplitDateTimePickerWidget(),

src/pretix/control/forms/subevents.py

@@ -12,7 +12,7 @@ from pretix.base.models.event import SubEvent, SubEventMetaValue
 from pretix.base.models.items import SubEventItem
 from pretix.base.reldate import RelativeDateTimeField
 from pretix.base.templatetags.money import money_filter
-from pretix.control.forms import SplitDateTimePickerWidget
+from pretix.control.forms import SplitDateTimeField, SplitDateTimePickerWidget
 from pretix.helpers.money import change_decimal_field
 
 
@@ -37,11 +37,11 @@ class SubEventForm(I18nModelForm):
             'frontpage_text'
         ]
         field_classes = {
-            'date_from': forms.SplitDateTimeField,
+            'date_from': SplitDateTimeField,
-            'date_to': forms.SplitDateTimeField,
+            'date_to': SplitDateTimeField,
-            'date_admission': forms.SplitDateTimeField,
+            'date_admission': SplitDateTimeField,
-            'presale_start': forms.SplitDateTimeField,
+            'presale_start': SplitDateTimeField,
-            'presale_end': forms.SplitDateTimeField,
+            'presale_end': SplitDateTimeField,
         }
         widgets = {
             'date_from': SplitDateTimePickerWidget(),

src/pretix/control/forms/vouchers.py

@@ -6,7 +6,7 @@ from django.utils.translation import pgettext_lazy, ugettext_lazy as _
 
 from pretix.base.forms import I18nModelForm
 from pretix.base.models import Item, Voucher
-from pretix.control.forms import SplitDateTimePickerWidget
+from pretix.control.forms import SplitDateTimeField, SplitDateTimePickerWidget
 from pretix.control.forms.widgets import Select2, Select2ItemVarQuota
 from pretix.control.signals import voucher_form_validation
 from pretix.helpers.models import modelcopy
@@ -34,7 +34,7 @@ class VoucherForm(I18nModelForm):
             'comment', 'max_usages', 'price_mode', 'subevent'
         ]
         field_classes = {
-            'valid_until': forms.SplitDateTimeField,
+            'valid_until': SplitDateTimeField,
         }
         widgets = {
             'valid_until': SplitDateTimePickerWidget(),
@@ -190,7 +190,7 @@ class VoucherBulkForm(VoucherForm):
             'max_usages', 'price_mode', 'subevent'
         ]
         field_classes = {
-            'valid_until': forms.SplitDateTimeField,
+            'valid_until': SplitDateTimeField,
         }
         widgets = {
             'valid_until': SplitDateTimePickerWidget(),