Demo of package:test with DEPS-vendored packages

Historically, flutter/engine used a homegrown test framework, package:litetest to avoid depending on the unwieldy set of dependencies that package:test brings in. However, package:test is now vendored in DEPS (used by the Dart SDK).'

This demo shows that:

• It's possible to use package:test with entirely local dependencies.
• The functionality of package:test (such as filtering, IDE integration, etc.) is available.

See https://github.com/flutter/flutter/issues/133569 for details.

Usage

Navigate to this directory:

cd testing/pkg_test_demo

And run the tests using dart test[^1]:

dart test

[^1]: In practice, you'll want to use the dart binary that is vendored in the pre-built SDK.