ab2b0851a2
This adds a smoke test for every single API example. It also fixes 17 tests that had bugs in them, or were otherwise broken, and even fixes one actual bug in the framework, and one limitation in the framework. The bug in the framework is that NetworkImage's _loadAsync method had await response.drain<List<int>>();, but if the response is null, it will throw a cryptic exception saying that Null can't be assigned to List<int>. The fix was just to use await response.drain<void>(); instead. The limitation is that RelativePositionedTransition takes an Animation<Rect> rect parameter, and if you want to use a RectTween with it, the value emitted there is Rect?, and one of the examples was just casting from Animation<Rect> to Animation<Rect?>, which is invalid, so I modified RelativePositionedTransition to take a Rect? and just use Rect.zero if the rect is null.
Private Test Runner
These are tests of private interfaces that can't easily happen in the regular flutter tests due to problems with test and implementation interdependence.
This gets around the problem of parts existing in more than one library by making a copy of the code under test.
The test script bin/test_private.dart tests private interfaces by copying the
code under test into a temporary workspace. The test is then free to make the
copied flutter source into a "part" of its own library by declaring a library
and using the part directive with a relative path to include the parts. This
way the test and the private interface are part of the same library, and the
private interface can be accessed by the test.
The tests are run like so:
pub run --enable-experiment=non-nullable test_private.dart
One limitation is that the copied private API needs to be separable enough to be copied, so it needs to be in its own separate files.
To add a private test, add a manifest file of the form (assuming "my_private_test" is the name of the test) to the test subdir:
{
"tests": [
"my_private_test.dart"
],
"pubspec": "my_private_test.pubspec.yaml",
"deps": [
"lib/src/subpackage/my_private_implementation.dart",
]
}
It will copy the files in deps relative to the packages/flutter directory
into a similar relative path structure in the test temporary directory tree. It
will copy the pubspec file into pubspec.yaml in the test temporary
directory, and copy all of the tests into the top of the test temporary
directory tree.
Each test gets its own temporary directory tree under a generated temporary
directory in the system temp dir that is removed at the end of the run, or under
the path given to --temp-dir on the command line. If a temporary directory is
given explicitly, it will not be deleted at the end of the run.