Make the subscript fetch call strict to resolve issue #5

src/collection_subs.c

@@ -270,7 +270,7 @@ collection_subscript_handler(PG_FUNCTION_ARGS)
 	static const SubscriptRoutines sbsroutines = {
 		.transform = collection_subscript_transform,
 		.exec_setup = collection_exec_setup,
-		.fetch_strict = false,	/* fetch returns NULL for NULL inputs */
+		.fetch_strict = true,	/* fetch returns NULL for NULL inputs */
 		.fetch_leakproof = true,	/* fetch returns NULL for bad subscript */
 		.store_leakproof = false	/* ... but assignment throws error */
 	};

test/expected/subscript.out

@@ -131,13 +131,13 @@ DO $$
 DECLARE
   u   collection('text');
 BEGIN
-  RAISE NOTICE 'Test 10';
+  RAISE NOTICE 'Subscript test 10';
   u := add(u, 'x1', 'Hello World'::text);
   u := add(u, 'y3', '12-31-1999'::date);
   RAISE NOTICE 'count: %', count(u);
 END
 $$;
-NOTICE:  Test 10
+NOTICE:  Subscript test 10
 ERROR:  Incompatible value data type
 DETAIL:  Expecting text, but received date
 CONTEXT:  PL/pgSQL function inline_code_block line 7 at assignment
@@ -148,7 +148,7 @@ DECLARE
   child1    collection('text');
   child2    collection('text');
 BEGIN
-  RAISE NOTICE 'Test 11';
+  RAISE NOTICE 'Subscript test 11';
 
   child1['aaa'] := 'Hello World';
   child1['bbb'] := 'Hello All';
@@ -162,5 +162,17 @@ BEGIN
   RAISE NOTICE 'Parent: %', parent;
 END
 $$;
-NOTICE:  Test 11
+NOTICE:  Subscript test 11
 NOTICE:  Parent: {"value_type": "public.collection", "entries": {"child1": "{\"value_type\": \"pg_catalog.text\", \"entries\": {\"aaa\": \"Hello World\", \"bbb\": \"Hello All\"}}", "child2": "{\"value_type\": \"pg_catalog.text\", \"entries\": {\"AAA\": \"Hallo Welt\", \"BBB\": \"Hola Mundo\"}}"}}
+DO
+$$
+DECLARE
+t collection;
+BEGIN
+  RAISE NOTICE 'Subscript test 12';
+
+  RAISE NOTICE 'The current val is %', t['2'];
+END
+$$;
+NOTICE:  Subscript test 12
+NOTICE:  The current val is <NULL>

test/sql/subscript.sql

@@ -119,7 +119,7 @@ DO $$
 DECLARE
   u   collection('text');
 BEGIN
-  RAISE NOTICE 'Test 10';
+  RAISE NOTICE 'Subscript test 10';
   u := add(u, 'x1', 'Hello World'::text);
   u := add(u, 'y3', '12-31-1999'::date);
   RAISE NOTICE 'count: %', count(u);
@@ -133,7 +133,7 @@ DECLARE
   child1    collection('text');
   child2    collection('text');
 BEGIN
-  RAISE NOTICE 'Test 11';
+  RAISE NOTICE 'Subscript test 11';
 
   child1['aaa'] := 'Hello World';
   child1['bbb'] := 'Hello All';
@@ -147,3 +147,14 @@ BEGIN
   RAISE NOTICE 'Parent: %', parent;
 END
 $$;
+
+DO
+$$
+DECLARE
+t collection;
+BEGIN
+  RAISE NOTICE 'Subscript test 12';
+
+  RAISE NOTICE 'The current val is %', t['2'];
+END
+$$;