-- C2 residual (1.5.4): ambulkdelete cleans INLINE postings.
--
-- Small posting lists (< PG_TRE_INLINE_POSTING_MAX TIDs per trigram)
-- are stored inline in the upper-tree leaf entry rather than in an
-- out-of-line posting tree.  Before 1.5.4 ambulkdelete skipped inline
-- postings; now it repacks the leaf's inline region in place.  This
-- test deletes rows, VACUUMs (driving ambulkdelete over inline
-- postings), and verifies (a) the index-scan row set still equals the
-- seq-scan row set, (b) deleted rows are gone, and (c) the in-place
-- inline rewrite did not corrupt the index (subsequent scans succeed).

CREATE EXTENSION IF NOT EXISTS pg_tre;

DROP TABLE IF EXISTS vinl;
CREATE TABLE vinl (id serial PRIMARY KEY, body text);

-- A modest row count keeps every trigram's posting list inline.
INSERT INTO vinl(body)
SELECT (ARRAY['apple pie','cherry tart','apple fritter','banana split',
              'apple cobbler','grape jelly','cherry cordial','plum cake'])[1 + (g % 8)]
FROM generate_series(1, 400) g;

SET client_min_messages = 'warning';
CREATE INDEX vinl_idx ON vinl USING tre (body);
RESET client_min_messages;

-- Drain anything pending into the inline postings first.
VACUUM vinl;

CREATE OR REPLACE FUNCTION vinl_diff(pat text) RETURNS text
LANGUAGE plpgsql AS $$
DECLARE seq_ids int[]; idx_ids int[];
BEGIN
  SET LOCAL enable_indexscan=off;
  SET LOCAL enable_bitmapscan=off;
  SET LOCAL enable_seqscan=on;
  EXECUTE format('SELECT array_agg(id ORDER BY id) FROM vinl '
                 'WHERE tre_amatch(body, %L, 0)', pat) INTO seq_ids;
  SET LOCAL enable_seqscan=off;
  SET LOCAL enable_indexscan=on;
  SET LOCAL enable_bitmapscan=on;
  EXECUTE format('SELECT array_agg(id ORDER BY id) FROM vinl '
                 'WHERE body %%~~ tre_pattern(%L, 0)', pat) INTO idx_ids;
  IF seq_ids IS NOT DISTINCT FROM idx_ids THEN
    RETURN 'OK  ' || pat;
  END IF;
  RETURN format('BAD %s  seq=%s  idx=%s', pat, seq_ids, idx_ids);
END$$;

-- Baseline: index agrees with the heap.
SELECT vinl_diff('apple');
SELECT vinl_diff('cherry');
SELECT vinl_diff('grape');

-- Delete a large fraction of rows, then VACUUM: ambulkdelete must strip
-- the dead TIDs from the inline postings.
DELETE FROM vinl WHERE id % 2 = 0;
VACUUM vinl;

-- After the inline rewrite, the index still agrees with the heap and
-- the deleted (even-id) rows are absent from both sides.
SELECT vinl_diff('apple');
SELECT vinl_diff('cherry');
SELECT vinl_diff('grape');
SELECT vinl_diff('banana');
SELECT vinl_diff('plum');

-- Delete everything matching one term, VACUUM, and confirm the emptied
-- inline posting matches nothing (and does not error).
DELETE FROM vinl WHERE body LIKE 'grape%';
VACUUM vinl;
SELECT vinl_diff('grape');   -- both sides empty
SELECT vinl_diff('apple');   -- unaffected term still consistent

DROP FUNCTION vinl_diff(text);
DROP INDEX vinl_idx;
DROP TABLE vinl;