[1.7.x] Fixed #22792 -- Updated checks for list_display_links in model admin

Backport of d8f19bb3b6 from master

django/contrib/admin/checks.py

@@ -779,7 +779,7 @@ class ModelAdminChecks(BaseModelAdminChecks):
                     obj=cls,
                     id='admin.E122',
                 ),
-            elif field_name in cls.list_display_links:
+            elif cls.list_display_links and field_name in cls.list_display_links:
                 return [
                     checks.Error(
                         "The value of '%s' cannot be in both 'list_editable' and 'list_display_links'." % field_name,
@@ -788,7 +788,10 @@ class ModelAdminChecks(BaseModelAdminChecks):
                         id='admin.E123',
                     )
                 ]
-            elif not cls.list_display_links and cls.list_display[0] in cls.list_editable:
+            # Check that list_display_links is set, and that the first values of list_editable and list_display are
+            # not the same. See ticket #22792 for the use case relating to this.
+            elif (cls.list_display[0] in cls.list_editable and cls.list_display[0] != cls.list_editable[0] and
+                  cls.list_display_links is not None):
                 return [
                     checks.Error(
                         "The value of '%s' refers to the first field in 'list_display' ('%s'), "

tests/modeladmin/tests.py

@@ -1518,3 +1518,27 @@ class CustomModelAdminTests(CheckTestCase):
                 validator_class = CustomValidator
 
             self.assertIsInvalid(CustomModelAdmin, ValidationTestModel, 'error!')
+
+
+class ListDisplayEditableTests(CheckTestCase):
+    def test_list_display_links_is_none(self):
+        """
+        list_display and list_editable can contain the same values
+        when list_display_links is None
+        """
+        class ProductAdmin(ModelAdmin):
+            list_display = ['name', 'slug', 'pub_date']
+            list_editable = list_display
+            list_display_links = None
+        self.assertIsValid(ProductAdmin, ValidationTestModel)
+
+    def test_list_display_same_as_list_editable(self):
+        """
+        The first item in list_display can be the same as the first
+        in list_editable
+        """
+        class ProductAdmin(ModelAdmin):
+            list_display = ['name', 'slug', 'pub_date']
+            list_editable = ['name', 'slug']
+            list_display_links = ['pub_date']
+        self.assertIsValid(ProductAdmin, ValidationTestModel)