Add fallback on full-word search to generic model IndexView

wagtail/admin/views/generic/models.py

@@ -1,3 +1,5 @@
+import warnings
+
 from django import VERSION as DJANGO_VERSION
 from django.contrib.admin.utils import label_for_field, quote, unquote
 from django.contrib.contenttypes.models import ContentType
@@ -254,9 +256,21 @@ class IndexView(LocaleMixin, PermissionCheckedMixin, BaseListingView):
 
         if class_is_indexed(queryset.model) and self.search_backend_name:
             search_backend = get_search_backend(self.search_backend_name)
-            return search_backend.autocomplete(
-                self.search_query, queryset, fields=self.search_fields
-            )
+            if queryset.model.get_autocomplete_search_fields():
+                return search_backend.autocomplete(
+                    self.search_query, queryset, fields=self.search_fields
+                )
+            else:
+                # fall back on non-autocompleting search
+                warnings.warn(
+                    f"{queryset.model} is defined as Indexable but does not specify "
+                    "any AutocompleteFields. Searches within the admin will only "
+                    "respond to complete words.",
+                    category=RuntimeWarning,
+                )
+                return search_backend.search(
+                    self.search_query, queryset, fields=self.search_fields
+                )
 
         filters = {
             field + "__icontains": self.search_query

wagtail/snippets/tests/test_snippets.py

@@ -509,6 +509,45 @@ class TestSnippetListViewWithSearchableSnippet(WagtailTestUtils, TransactionTest
         self.assertIn(self.snippet_c, items)
 
 
+class TestSnippetListViewWithNonAutocompleteSearchableSnippet(
+    WagtailTestUtils, TransactionTestCase
+):
+    """
+    Test that searchable snippets with no AutocompleteFields defined can still be searched using
+    full words
+    """
+
+    def setUp(self):
+        self.login()
+
+        # Create some instances of the searchable snippet for testing
+        self.snippet_a = NonAutocompleteSearchableSnippet.objects.create(text="Hello")
+        self.snippet_b = NonAutocompleteSearchableSnippet.objects.create(text="World")
+        self.snippet_c = NonAutocompleteSearchableSnippet.objects.create(
+            text="Hello World"
+        )
+
+    def get(self, params={}):
+        return self.client.get(
+            reverse(
+                "wagtailsnippets_snippetstests_nonautocompletesearchablesnippet:list"
+            ),
+            params,
+        )
+
+    def test_search_hello(self):
+        with self.assertWarnsRegex(
+            RuntimeWarning, "does not specify any AutocompleteFields"
+        ):
+            response = self.get({"q": "Hello"})
+
+        # Just snippets with "Hello" should be in items
+        items = list(response.context["page_obj"].object_list)
+        self.assertIn(self.snippet_a, items)
+        self.assertNotIn(self.snippet_b, items)
+        self.assertIn(self.snippet_c, items)
+
+
 class TestSnippetCreateView(WagtailTestUtils, TestCase):
     def setUp(self):
         self.user = self.login()