fix: unexpected results when embedding the same table twice

Author: laurenceisla

src/PostgREST/Plan.hs

@@ -968,7 +968,7 @@ updateNode f (targetNodeName:remainingPath, a) (Right (Node rootNode forest)) =
       updateNode f (remainingPath, a) (Right target)
   where
     findNode :: Maybe ReadPlanTree
-    findNode = find (\(Node ReadPlan{relName, relAlias} _) -> relName == targetNodeName || relAlias == Just targetNodeName) forest
+    findNode = find (\(Node ReadPlan{relName, relAlias} _) -> fromMaybe relName relAlias == targetNodeName) forest
 
 mutatePlan :: Mutation -> QualifiedIdentifier -> ApiRequest -> SchemaCache -> ReadPlanTree -> Either Error MutatePlan
 mutatePlan mutation qi ApiRequest{iPreferences=Preferences{..}, ..} SchemaCache{dbTables, dbRepresentations} readReq =

test/spec/Feature/Query/QuerySpec.hs

@@ -1056,6 +1056,16 @@ spec = do
             { "id":4,"children":[]}
           ]|] { matchHeaders = [matchContentTypeJson] }
 
+      it "works when embedding the same table more than once" $
+        get "/places?select=name,visits(id,start_time,visit_type),work_visits:visits(id,start_time,visit_type)&id=eq.1&visits.visit_type=neq.work&visits.start_time=gt.20250101+00:00&work_visits.visit_type=eq.work&work_visits.start_time=gt.20250101+00:00" `shouldRespondWith`
+          [json|[
+            {
+              "name":"Lake",
+              "visits":[{"id": 1, "start_time": "2025-01-01T10:00:00", "visit_type": "vacation"}, {"id": 2, "start_time": "2025-01-01T15:00:00", "visit_type": "vacation"}],
+              "work_visits":[{"id": 3, "start_time": "2025-01-01T20:00:00", "visit_type": "work"}]
+            }
+          ]|] { matchHeaders = [matchContentTypeJson] }
+
   describe "ordering response" $ do
     it "by a column asc" $
       get "/items?id=lte.2&order=id.asc"
@@ -1138,7 +1148,7 @@ spec = do
         { matchHeaders = [matchContentTypeJson] }
 
     it "ordering embeded entities with alias" $
-      get "/projects?id=eq.1&select=id, name, the_tasks:tasks(id, name)&tasks.order=name.asc" `shouldRespondWith`
+      get "/projects?id=eq.1&select=id, name, the_tasks:tasks(id, name)&the_tasks.order=name.asc" `shouldRespondWith`
         [json|[{"id":1,"name":"Windows 7","the_tasks":[{"id":2,"name":"Code w7"},{"id":1,"name":"Design w7"}]}]|]
         { matchHeaders = [matchContentTypeJson] }
 

test/spec/fixtures/data.sql

@@ -961,8 +961,21 @@ INSERT INTO artists
 VALUES (1, 'duster'), (2, 'black country, new road'), (3, 'bjork');
 
 TRUNCATE TABLE albums CASCADE;
-INSERT INTO albums 
+INSERT INTO albums
 VALUES (1, 'stratosphere', 1),
-       (2, 'ants from up above',2), 
+       (2, 'ants from up above',2),
        (3, 'vespertine',3),
        (4, 'contemporary movement', 1);
+
+TRUNCATE TABLE places CASCADE;
+INSERT INTO places (name)
+VALUES ('Lake'), ('Mountain'), ('Beach');
+
+TRUNCATE TABLE visits CASCADE;
+INSERT INTO visits (place_id, start_time, end_time, visit_type)
+VALUES (1, '2025-01-01 10:00','2025-01-01 11:00', 'vacation'),
+       (1, '2025-01-01 15:00','2025-01-01 16:00', 'vacation'),
+       (1, '2025-01-01 20:00', '2025-01-01 21:00', 'work'),
+       (2, '2024-11-01 09:00','2024-11-01 10:00', 'vacation'),
+       (3, '2024-12-02 13:00','2024-12-02 14:00', 'vacation'),
+       (1, '2023-01-02 20:00','2023-01-01 21:00', 'work');

test/spec/fixtures/schema.sql

@@ -3820,3 +3820,18 @@ comment on function test.collision_test_func(id integer) is 'fizzbuzz';
 create or replace function test.delete_all_items() returns setof items as $$
   delete from items where id <= 15 returning *; -- deletes 15 items, then return them
 $$ language sql;
+
+create type visit_type as enum ('vacation', 'work');
+
+create table places (
+  id int primary key generated always as identity,
+  name text not null
+);
+
+create table visits (
+  id int primary key generated always as identity,
+  place_id int not null references places(id),
+  start_time timestamp,
+  end_time timestamp,
+  visit_type visit_type
+);