Fixed #28040 -- Updated SplitArrayWidget to use template-based widget rendering.

Thanks Preston Timmons for review.

django/contrib/postgres/forms/array.py

@@ -6,7 +6,6 @@ from django.contrib.postgres.validators import (
     ArrayMaxLengthValidator, ArrayMinLengthValidator,
 )
 from django.core.exceptions import ValidationError
-from django.utils.safestring import mark_safe
 from django.utils.translation import gettext_lazy as _
 
 from ..utils import prefix_validation_error
@@ -90,6 +89,7 @@ class SimpleArrayField(forms.CharField):
 
 
 class SplitArrayWidget(forms.Widget):
+    template_name = 'postgres/widgets/split_array.html'
 
     def __init__(self, widget, size, **kwargs):
         self.widget = widget() if isinstance(widget, type) else widget
@@ -116,11 +116,13 @@ class SplitArrayWidget(forms.Widget):
             id_ += '_0'
         return id_
 
-    def render(self, name, value, attrs=None, renderer=None):
+    def get_context(self, name, value, attrs=None):
+        attrs = {} if attrs is None else attrs
+        context = super().get_context(name, value, attrs)
         if self.is_localized:
             self.widget.is_localized = self.is_localized
         value = value or []
-        output = []
+        context['widget']['subwidgets'] = []
         final_attrs = self.build_attrs(attrs)
         id_ = final_attrs.get('id')
         for i in range(max(len(value), self.size)):
@@ -130,11 +132,10 @@ class SplitArrayWidget(forms.Widget):
                 widget_value = None
             if id_:
                 final_attrs = dict(final_attrs, id='%s_%s' % (id_, i))
-            output.append(self.widget.render(name + '_%s' % i, widget_value, final_attrs, renderer))
-        return mark_safe(self.format_output(output))
-
-    def format_output(self, rendered_widgets):
-        return ''.join(rendered_widgets)
+            context['widget']['subwidgets'].append(
+                self.widget.get_context(name + '_%s' % i, widget_value, final_attrs)['widget']
+            )
+        return context
 
     @property
     def media(self):

django/contrib/postgres/jinja2/postgres/widgets/split_array.html

+{% include 'django/forms/widgets/multiwidget.html' %}

django/contrib/postgres/templates/postgres/widgets/split_array.html

+{% include 'django/forms/widgets/multiwidget.html' %}

docs/releases/1.11.1.txt

@@ -63,3 +63,6 @@ Bugfixes
   that have initial data (:ticket:`28130`).
 
 * Prepared for ``cx_Oracle`` 6.0 support (:ticket:`28138`).
+
+* Updated the ``contrib.postgres`` ``SplitArrayWidget`` to use template-based
+  widget rendering (:ticket:`28040`).

tests/postgres_tests/__init__.py

 import unittest
 
+from forms_tests.widget_tests.base import WidgetTest
+
 from django.db import connection
 from django.db.backends.signals import connection_created
-from django.test import TestCase
+from django.test import TestCase, modify_settings
 
 
 @unittest.skipUnless(connection.vendor == 'postgresql', "PostgreSQL specific tests")
@@ -14,3 +16,10 @@ class PostgreSQLTestCase(TestCase):
 
         connection_created.disconnect(register_hstore_handler)
         super().tearDownClass()
+
+
+@unittest.skipUnless(connection.vendor == 'postgresql', "PostgreSQL specific tests")
+# To locate the widget's template.
+@modify_settings(INSTALLED_APPS={'append': 'django.contrib.postgres'})
+class PostgreSQLWidgetTestCase(WidgetTest):
+    pass

tests/postgres_tests/test_array.py

@@ -8,11 +8,11 @@ from django.core import exceptions, serializers, validators
 from django.core.exceptions import FieldError
 from django.core.management import call_command
 from django.db import IntegrityError, connection, models
-from django.test import TransactionTestCase, override_settings
+from django.test import TransactionTestCase, modify_settings, override_settings
 from django.test.utils import isolate_apps
 from django.utils import timezone
 
-from . import PostgreSQLTestCase
+from . import PostgreSQLTestCase, PostgreSQLWidgetTestCase
 from .models import (
     ArrayFieldSubclass, CharArrayModel, DateTimeArrayModel, IntegerArrayModel,
     NestedIntegerArrayModel, NullableIntegerArrayModel, OtherTypesArrayModel,
@@ -749,6 +749,8 @@ class TestSplitFormField(PostgreSQLTestCase):
         with self.assertRaisesMessage(exceptions.ValidationError, msg):
             SplitArrayField(forms.IntegerField(max_value=100), size=2).clean([0, 101])
 
+    # To locate the widget's template.
+    @modify_settings(INSTALLED_APPS={'append': 'django.contrib.postgres'})
     def test_rendering(self):
         class SplitForm(forms.Form):
             array = SplitArrayField(forms.CharField(), size=3)
@@ -787,7 +789,63 @@ class TestSplitFormField(PostgreSQLTestCase):
         self.assertEqual(obj.field, [1, 2])
 
 
-class TestSplitFormWidget(PostgreSQLTestCase):
+class TestSplitFormWidget(PostgreSQLWidgetTestCase):
+
+    def test_get_context(self):
+        self.assertEqual(
+            SplitArrayWidget(forms.TextInput(), size=2).get_context('name', ['val1', 'val2']),
+            {
+                'widget': {
+                    'name': 'name',
+                    'is_hidden': False,
+                    'required': False,
+                    'value': "['val1', 'val2']",
+                    'attrs': {},
+                    'template_name': 'postgres/widgets/split_array.html',
+                    'subwidgets': [
+                        {
+                            'name': 'name_0',
+                            'is_hidden': False,
+                            'required': False,
+                            'value': 'val1',
+                            'attrs': {},
+                            'template_name': 'django/forms/widgets/text.html',
+                            'type': 'text',
+                        },
+                        {
+                            'name': 'name_1',
+                            'is_hidden': False,
+                            'required': False,
+                            'value': 'val2',
+                            'attrs': {},
+                            'template_name': 'django/forms/widgets/text.html',
+                            'type': 'text',
+                        },
+                    ]
+                }
+            }
+        )
+
+    def test_render(self):
+        self.check_html(
+            SplitArrayWidget(forms.TextInput(), size=2), 'array', None,
+            """
+            <input name="array_0" type="text" />
+            <input name="array_1" type="text" />
+            """
+        )
+
+    def test_render_attrs(self):
+        self.check_html(
+            SplitArrayWidget(forms.TextInput(), size=2),
+            'array', ['val1', 'val2'], attrs={'id': 'foo'},
+            html=(
+                """
+                <input id="foo_0" name="array_0" type="text" value="val1" />
+                <input id="foo_1" name="array_1" type="text" value="val2" />
+                """
+            )
+        )
 
     def test_value_omitted_from_data(self):
         widget = SplitArrayWidget(forms.TextInput(), size=2)