fix: make tree sorting case insensitive

openedx_tagging/core/tagging/models/base.py

@@ -9,7 +9,7 @@
 from django.core.exceptions import ValidationError
 from django.db import models
 from django.db.models import F, Q, Value
-from django.db.models.functions import Concat
+from django.db.models.functions import Concat, Lower
 from django.utils.functional import cached_property
 from django.utils.module_loading import import_string
 from django.utils.translation import gettext_lazy as _
@@ -462,7 +462,7 @@ def _get_filtered_tags_deep(
         # Add the "depth" to each tag:
         qs = Tag.annotate_depth(qs)
         # Add the "lineage" as a field called "sort_key" to sort them in order correctly:
-        qs = qs.annotate(sort_key=Concat(
+        qs = qs.annotate(sort_key=Lower(Concat(
             # For a root tag, we want sort_key="RootValue" and for a depth=1 tag
             # we want sort_key="RootValue\tValue". The following does that, since
             # ConcatNull(...) returns NULL if any argument is NULL.
@@ -472,7 +472,7 @@ def _get_filtered_tags_deep(
             F("value"),
             Value("\t"),  # We also need the '\t' separator character at the end, or MySQL will sort things wrong
             output_field=models.CharField(),
-        ))
+        )))
         # Add the parent value
         qs = qs.annotate(parent_value=F("parent__value"))
         qs = qs.annotate(_id=F("id"))  # ID has an underscore to encourage use of 'value' rather than this internal ID

tests/openedx_tagging/core/tagging/test_models.py

@@ -472,6 +472,43 @@ def test_pathological_tree_sort(self) -> None:
             "  123 (111) (used: 0, children: 0)",
         ]
 
+    def test_case_insensitive_sort(self) -> None:
+        """
+        Make sure the sorting is case-insensitive
+        """
+        # pylint: disable=unused-variable
+        taxonomy = api.create_taxonomy("Sort Test")
+        root1 = Tag.objects.create(taxonomy=taxonomy, value="ALPHABET")
+        child1_1 = Tag.objects.create(taxonomy=taxonomy, value="Android", parent=root1)
+        child1_2 = Tag.objects.create(taxonomy=taxonomy, value="abacus", parent=root1)
+        child1_3 = Tag.objects.create(taxonomy=taxonomy, value="aardvark", parent=root1)
+        child1_4 = Tag.objects.create(taxonomy=taxonomy, value="ANVIL", parent=root1)
+
+        root2 = Tag.objects.create(taxonomy=taxonomy, value="abstract")
+        child2_1 = Tag.objects.create(taxonomy=taxonomy, value="Andes", parent=root2)
+        child2_2 = Tag.objects.create(taxonomy=taxonomy, value="azores islands", parent=root2)
+
+        result = pretty_format_tags(taxonomy.get_filtered_tags())
+        assert result == [
+            "abstract (None) (used: 0, children: 2)",
+            "  Andes (abstract) (used: 0, children: 0)",
+            "  azores islands (abstract) (used: 0, children: 0)",
+            "ALPHABET (None) (used: 0, children: 4)",
+            "  aardvark (ALPHABET) (used: 0, children: 0)",
+            "  abacus (ALPHABET) (used: 0, children: 0)",
+            "  Android (ALPHABET) (used: 0, children: 0)",
+            "  ANVIL (ALPHABET) (used: 0, children: 0)",
+        ]
+
+        # And it's case insensitive when getting only a single level:
+        result = pretty_format_tags(taxonomy.get_filtered_tags(parent_tag_value="ALPHABET", depth=1))
+        assert result == [
+            "  aardvark (ALPHABET) (used: 0, children: 0)",
+            "  abacus (ALPHABET) (used: 0, children: 0)",
+            "  Android (ALPHABET) (used: 0, children: 0)",
+            "  ANVIL (ALPHABET) (used: 0, children: 0)",
+        ]
+
 
 class TestFilteredTagsFreeTextTaxonomy(TestCase):
     """