Using pgTAP, can i select values/records into variables to use in the test?

Question

I have a test factory function that creates and returns single records:

CREATE FUNCTION build_rec_for_test()
RETURNS mytable
AS $$
   INSERT INTO mytable VALUES (rand_uuid(),rand_int(),rand_int()) RETURNING *;
$$ LANGUAGE sql;

Is there a way to easily use that return value in pgTAP?

I'm basically looking to treat the return value as a variable, but maybe I'm too locked in the "regular" procedural style of thought.

A DO block is not useful - it does not write to stdout (link).

I'd like to do something like

BEGIN;
SELECT plan(1);

DECLARE my_rec = build_rec_for_test();

-- perform a test with values from the factory function
SELECT is(SELECT id FROM mytable, my_rec.id); 

SELECT * FROM finish();
ROLLBACK;

A more complete example might be something like

BEGIN;
SELECT plan(1);

DECLARE author = create_mock_author();
DECLARE post1 = create_mock_post_for(author);
DECLARE post2 = create_mock_post_for(author);
DECLARE comment1 = create_mock_comment_for(post1);
DECLARE comment2 = create_mock_comment_for(post2);

-- perform a test with values from the factory function
SELECT is(
    SELECT status FROM comments WHERE id = comment1.id, 
    'IN_REVIEW'
); 

-- I realize this is not a good test, because create_mock_post_for
-- will set the value, but it's an example of using an intermediate
-- record as part of the test
SELECT is(
    SELECT author_id FROM posts WHERE id = post1.id,
    author.id
);

SELECT * FROM finish();
ROLLBACK;

But obviously, that's not valid syntax.

Is there a way to accomplish this?

Answer 1

This appears to work nicely:

BEGIN;
SELECT plan(2);

CREATE FUNCTION test_schema.test1()
RETURNS SETOF TEXT
AS $$
DECLARE
  parent1 parent_type;
  parent2 parent_type;
  child1 child_type;
  child2 child_type;
BEGIN

  SELECT * INTO parent1 FROM create_mock_parent();
  SELECT * INTO parent2 FROM create_mock_parent();
  SELECT * INTO child1 FROM create_mock_child(parent_id := parent1.id);
  SELECT * INTO child2 FROM create_mock_child(parent_id := parent2.id);

  RETURN QUERY SELECT is(parent1.id, child1.parent_id);
  RETURN QUERY SELECT is(parent2.id, child2.parent_id);

END;
$$ LANGUAGE plpgsql;

SELECT * FROM test_schema.test1();

SELECT * FROM finish();
ROLLBACK;