Fix #1242, embed a view having a select in a where

CHANGELOG.md

@@ -13,6 +13,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 
 - #1223, Fix incorrect OpenAPI externalDocs url - @steve-chavez
 - #1221, Fix embedding other resources when having a self join - @steve-chavez
+- #1242, Fix embedding a view having a select in a where - @steve-chavez
 
 ## [5.2.0] - 2018-12-12
 

src/PostgREST/DbStructure.hs

@@ -707,8 +707,11 @@ allSynonyms cols pgVer =
   -- query explanation at https://gist.github.com/steve-chavez/7ee0e6590cddafb532e5f00c46275569
   where
     subselectRegex :: Text
-    subselectRegex | pgVer < pgVersion100 = ":subselect {.*?:constraintDeps <>} :location"
+    -- "result" appears when the subselect is used inside "case when", see `authors_have_book_in_decade` fixture
-                   | otherwise = ":subselect {.*?:stmt_len 0} :location"
+    -- "resno"  appears in every other case
+    -- when copying the query into pg make sure you omit one backslash from \\d+, it should be like `\d+` for the regex
+    subselectRegex | pgVer < pgVersion100 = ":subselect {.*?:constraintDeps <>} :location \\d+} :res(no|ult)"
+                   | otherwise = ":subselect {.*?:stmt_len 0} :location \\d+} :res(no|ult)"
     sql = [qc|
       with
       views as (

test/Feature/QuerySpec.hs

@@ -433,6 +433,11 @@ spec = do
              {"number_of_projects":2,"client":{"name":"Apple"}}] |]
           { matchHeaders = [matchContentTypeJson] }
 
+      it "can embed a view that has a subselect containing a select in a where" $
+        get "/authors_w_entities?select=name,entities,books(title)&id=eq.1" `shouldRespondWith`
+          [json| [{"name":"George Orwell","entities":[3, 4],"books":[{"title":"1984"}]}] |]
+          { matchHeaders = [matchContentTypeJson] }
+
     describe "path fixed" $ do
       it "works when requesting children 2 levels" $
         get "/clients?id=eq.1&select=id,projects:projects.client_id(id,tasks(id))" `shouldRespondWith`

test/fixtures/privileges.sql

@@ -99,6 +99,7 @@ GRANT ALL ON TABLE
     , projects_count_grouped_by
     , "Server Today"
     , pgrst_reserved_chars
+    , authors_w_entities
 TO postgrest_test_anonymous;
 
 GRANT INSERT ON TABLE insertonly TO postgrest_test_anonymous;

test/fixtures/schema.sql

@@ -1545,6 +1545,19 @@ select
 from projects
 group by client_id;
 
+create view test.authors_w_entities as
+select
+  id,
+  name,
+  (
+    select json_agg(id)
+    from test.entities
+    where id not in (
+      select parent_id from test.child_entities
+    )
+  ) as entities
+from private.authors;
+
 CREATE TABLE test."Foo"(
   id int primary key,
   name text