Test helpers

Three helpers under ORM::ActiveRecord::Testing keep test data isolated and easy to set up: a transactional wrapper, a YAML fixture loader, and a database cleaner.

Transactional tests#

Wrapping each example in a transaction that is rolled back at teardown leaves the database untouched between tests, with no DELETE or TRUNCATE. Nested model transactions join the open one (via savepoints), so a test's own transaction { ... } still behaves.

use ORM::ActiveRecord::Testing::Transaction;

before-each { begin-transactional-test }
after-each  { rollback-transactional-test }

Or wrap a single body:

with-rollback {
  User.create({ fname => 'Ada' });
  expect(User.count).to.eq(1);
};   # the row is gone here

begin-transactional-test accepts an :isolation level (READ COMMITTED, REPEATABLE READ, ...).

Fixtures#

Fixtures are YAML files, one per table (the filename is the table name). Each top-level key is a label; its id is derived deterministically from the label, so references resolve across files regardless of load order.

# authors.yml
alice:
  name: Alice
  admin: <%= True %>
bob:
  name: Bob

# articles.yml
hello:
  title: Hello World
  author: alice          # belongs-to: author_id = identify('alice')

use ORM::ActiveRecord::Testing::Fixtures;

my $fx = Fixtures.new(dir => 'test/fixtures').load;

$fx.id('authors', 'alice');        # the deterministic id
$fx.record('articles', 'hello');   # the inserted row hash
$fx.labels('authors');             # ('alice', 'bob')

Loading deletes the table's existing rows first, so it is repeatable.

Interpolation#

<%= expr %> in a value is replaced by the stringified result of the Raku expression before the YAML is parsed.

created_at: <%= DateTime.now %>
admin: <%= True %>

References between files#

A key that is not a column but whose <key>_id is a column is treated as a belongs-to reference: the value names another fixture's label, and the loader sets <key>_id to that label's deterministic id. Because the id comes from the label alone, the referenced file need not be loaded first (or at all).

Fixtures.new.identify('alice');    # the same id 'author: alice' resolves to

Database cleaner#

When you are not using the transactional wrapper, clean explicitly:

use ORM::ActiveRecord::Testing::DatabaseCleaner;

my $cleaner = DatabaseCleaner.new;

$cleaner.clean;                          # deletion (DELETE FROM every table)
$cleaner.clean(strategy => 'truncation');# TRUNCATE / reset identities

truncation issues TRUNCATE ... RESTART IDENTITY CASCADE on PostgreSQL, disables foreign-key checks around TRUNCATE on MySQL, and falls back to DELETE (plus clearing sqlite_sequence) on SQLite.

The transaction strategy runs a block and rolls it back, like the wrapper:

$cleaner.cleaning({
  # writes here are discarded
}, strategy => 'transaction');

The migrations table is never touched. Pass except => <migrations other> to spare more tables.