Merge pull request #6268 from matrix-org/erikj/case_insensitive_room_dir

* commit '1652c8c1f':
  Add comment as to why we're pinning black in tests
  Pin black version
  Newsfile
  Make room directory search case insensitive

changelog.d/6286.bugfix

@@ -0,0 +1 @@
+Fix bug where room directory search was case sensitive.

synapse/storage/data_stores/main/room.py

@@ -204,13 +204,17 @@ def get_largest_public_rooms(
             where_clauses.append(
                 """
                     (
-                        name LIKE ?
-                        OR topic LIKE ?
-                        OR canonical_alias LIKE ?
+                        LOWER(name) LIKE ?
+                        OR LOWER(topic) LIKE ?
+                        OR LOWER(canonical_alias) LIKE ?
                     )
                 """
             )
-            query_args += [search_term, search_term, search_term]
+            query_args += [
+                search_term.lower(),
+                search_term.lower(),
+                search_term.lower(),
+            ]
 
         where_clause = ""
         if where_clauses:

tox.ini

@@ -114,7 +114,7 @@ skip_install = True
 basepython = python3.6
 deps =
     flake8
-    black==19.3b0
+    black==19.3b0  # We pin so that our tests don't start failing on new releases of black.
 commands =
     python -m black --check --diff .
     /bin/sh -c "flake8 synapse tests scripts scripts-dev scripts/hash_password scripts/register_new_matrix_user scripts/synapse_port_db synctl {env:PEP8SUFFIX:}"