Add tests

src/test/regress/expected/multi_test_helpers.out

@@ -605,3 +605,29 @@ BEGIN
     RETURN NEXT;
   END LOOP;
 END; $$ language plpgsql;
+-- To produce stable regression test output, it's usually necessary to
+-- ignore details such as exact costs or row counts.  These filter
+-- functions replace changeable output details with fixed strings.
+-- Copied from PG explain.sql
+create function explain_filter(text) returns setof text
+language plpgsql as
+$$
+declare
+    ln text;
+begin
+    for ln in execute $1
+    loop
+        -- Replace any numeric word with just 'N'
+        ln := regexp_replace(ln, '-?\m\d+\M', 'N', 'g');
+        -- In sort output, the above won't match units-suffixed numbers
+        ln := regexp_replace(ln, '\m\d+kB', 'NkB', 'g');
+        -- Ignore text-mode buffers output because it varies depending
+        -- on the system state
+        CONTINUE WHEN (ln ~ ' +Buffers: .*');
+        -- Ignore text-mode "Planning:" line because whether it's output
+        -- varies depending on the system state
+        CONTINUE WHEN (ln = 'Planning:');
+        return next ln;
+    end loop;
+end;
+$$;

src/test/regress/sql/multi_test_helpers.sql

@@ -632,3 +632,31 @@ BEGIN
     RETURN NEXT;
   END LOOP;
 END; $$ language plpgsql;
+
+-- To produce stable regression test output, it's usually necessary to
+-- ignore details such as exact costs or row counts.  These filter
+-- functions replace changeable output details with fixed strings.
+-- Copied from PG explain.sql
+
+create function explain_filter(text) returns setof text
+language plpgsql as
+$$
+declare
+    ln text;
+begin
+    for ln in execute $1
+    loop
+        -- Replace any numeric word with just 'N'
+        ln := regexp_replace(ln, '-?\m\d+\M', 'N', 'g');
+        -- In sort output, the above won't match units-suffixed numbers
+        ln := regexp_replace(ln, '\m\d+kB', 'NkB', 'g');
+        -- Ignore text-mode buffers output because it varies depending
+        -- on the system state
+        CONTINUE WHEN (ln ~ ' +Buffers: .*');
+        -- Ignore text-mode "Planning:" line because whether it's output
+        -- varies depending on the system state
+        CONTINUE WHEN (ln = 'Planning:');
+        return next ln;
+    end loop;
+end;
+$$;

src/test/regress/sql/pg17.sql

@@ -1038,6 +1038,48 @@ DROP EVENT TRIGGER reindex_event_trigger_end;
 DROP TABLE reindex_test CASCADE;
 
 -- End of test for REINDEX support in event triggers for Citus-related objects
+-- Propagate EXPLAIN MEMORY
+-- Relevant PG commit: https://github.com/postgres/postgres/commit/5de890e36
+-- Propagate EXPLAIN SERIALIZE
+-- Relevant PG commit: https://github.com/postgres/postgres/commit/06286709e
+
+SET citus.next_shard_id TO 12242024;
+CREATE TABLE int8_tbl(q1 int8, q2 int8);
+SELECT create_distributed_table('int8_tbl', 'q1');
+INSERT INTO int8_tbl VALUES
+  ('  123   ','  456'),
+  ('123   ','4567890123456789'),
+  ('4567890123456789','123'),
+  (+4567890123456789,'4567890123456789'),
+  ('+4567890123456789','-4567890123456789');
+
+-- memory tests, same as postgres tests, we just distributed the table
+-- we can see the memory used separately per each task in worker nodes
+
+SET citus.log_remote_commands TO true;
+
+-- for explain analyze, we run worker_save_query_explain_analyze query
+-- for regular explain, we run EXPLAIN query
+-- therefore let's grep the commands based on the shard id
+SET citus.grep_remote_commands TO '%12242024%';
+
+select public.explain_filter('explain (memory) select * from int8_tbl i8');
+select public.explain_filter('explain (memory, analyze) select * from int8_tbl i8');
+select public.explain_filter('explain (memory, summary, format yaml) select * from int8_tbl i8');
+select public.explain_filter('explain (memory, analyze, format json) select * from int8_tbl i8');
+prepare int8_query as select * from int8_tbl i8;
+select public.explain_filter('explain (memory) execute int8_query');
+
+-- serialize tests, same as postgres tests, we just distributed the table
+select public.explain_filter('explain (analyze, serialize, buffers, format yaml) select * from int8_tbl i8');
+select public.explain_filter('explain (analyze,serialize) select * from int8_tbl i8');
+select public.explain_filter('explain (analyze,serialize text,buffers,timing off) select * from int8_tbl i8');
+select public.explain_filter('explain (analyze,serialize binary,buffers,timing) select * from int8_tbl i8');
+-- this tests an edge case where we have no data to return
+select public.explain_filter('explain (analyze,serialize) create temp table explain_temp as select * from int8_tbl i8');
+
+RESET citus.log_remote_commands;
+-- End of EXPLAIN MEMORY SERIALIZE tests
 
 \set VERBOSITY terse
 SET client_min_messages TO WARNING;