Fixed #21870 -- Admin check for list_editable_item

During the admin check for list_editable _check_list_editable_item
should return an empty list if all checks pass. Additionally the
Testcase test_readonly_and_editable was changed to test what the
name implies instead of duplicating the logic of test_readonly.

2 files changed, 26 insertions, 0 deletions

diff --git a/django/contrib/admin/checks.py b/django/contrib/admin/checks.py
index 515cedcf69..f768374d54 100644
--- a/django/contrib/admin/checks.py
+++ b/django/contrib/admin/checks.py
@@ -791,6 +791,8 @@ class ModelAdminChecks(BaseModelAdminChecks):
                         id='admin.E126',
                     )
                 ]
+            else:
+                return []
 
     def _check_search_fields(self, cls, model):
         """ Check search_fields is a sequence. """
diff --git a/tests/admin_checks/tests.py b/tests/admin_checks/tests.py
index 934e3f391e..c0ce428e67 100644
--- a/tests/admin_checks/tests.py
+++ b/tests/admin_checks/tests.py
@@ -52,6 +52,30 @@ class SystemChecksTestCase(TestCase):
     def test_readonly_and_editable(self):
         class SongAdmin(admin.ModelAdmin):
             readonly_fields = ["original_release"]
+            list_display = ["pk", "original_release"]
+            list_editable = ["original_release"]
+            fieldsets = [
+                (None, {
+                    "fields": ["title", "original_release"],
+                }),
+            ]
+
+        errors = SongAdmin.check(model=Song)
+        expected = [
+            checks.Error(
+                ('"list_editable[0]" refers to field "original_release", '
+                    'whih is not editable through the admin.'),
+                hint=None,
+                obj=SongAdmin,
+                id='admin.E126',
+            )
+        ]
+        self.assertEqual(errors, expected)
+
+    def test_editable(self):
+        class SongAdmin(admin.ModelAdmin):
+            list_display = ["pk", "title"]
+            list_editable = ["title"]
             fieldsets = [
                 (None, {
                     "fields": ["title", "original_release"],