Snapshots

[markhuot]

Snapshots

A variety of snapshot assertions are available to help you test your HTML and DOM output in craft-pest. In many places you can simply expect an object ->toMatchSnapshot() and Pest will handle the rest for you.

The two entrypoints to snapshotting are,

• expect($object)->toMatchSnapshot()
• $this->assertMatchesSnapshot()

For example, responses, DOM Lists, and views are all snapshotable.

it('matches responses')->get('/')->assertMatchesSnapshot();
it('matches dom lists')->get('/')->querySelector('h1')->assertMatchesSnapshot();
it('matches views')->renderTemplate('_news/entry', $variables)->assertMatchesSnapshot();

Elements

Many elements can be snapshotted as well. When using assertions Pest will automatically handle the conversion from an Element to a snapshot.

Entry::factory()->title('foo')->create()->assertMatchesSnapshot();

Unfortunately, Pest is not smart enough to properly snapshot elements in an expectation so you must call ->toSnapshot() on them first.

it('imports entries', function () {
  $this->importEntries();
  $entry = Entry::find()->section('news')->one();

  expect($entry->toSnapshot())->toMatchSnapshot();
});

Attributes

Only a subset of attributes from the element are snapshotted so dynamic fields do not create unexpected failures. For example, the $entry->postDate defaults to the current time when the entry was generated. That means running the test on Tuesday and again on Wednesday would fail the test because the postDate would be Tuesday in the initial snapshot and Wednesday during the comparison.

If you'd like to include additional attributes in the snapshot you can pass them as an array to the ->toSnapshot() method. For example,

it('snapshots postDate', function () {
  $entry = Entry::factory()->postDate('2022-01-01')->create();

  expect($entry->toSnapshot(['postDate']))->toMatchSnapshot();
  $entry->assertMatchesSnapshot(['postDate']);
});