Patrol Finder fails intermittently, why?

[philipmjohnson]

Flutter: 3.24.4
Dart: 3.5.4
Patrol Finders: 2.1.3 (also tested with 2.2.0+1, same results)

I have added a new integration test recently that looks like this:

Future<void> testPlantingCreateCropAndVariety(PatrolTester $) async {
  // Get to the Create Planting Screen
  String testCropName = 'AAPlantCrop';
  String testVarietyName = 'AAPlantVariety';
  await gotoCreatePlantingScreen($);
  // Create a new Crop
  await $(CreateButton).at(0).tap();
  expect($(CreateCropScreen).visible, equals(true));
  await $(CropNameField).enterText(testCropName);
  await $(FamilyDropdown).tap();
  await $('Allium').scrollTo(scrollDirection: AxisDirection.up).tap();
  await $(FormButtons).$('Submit').tap();
  expect($(CreatePlantingScreen).visible, equals(true));
  // Select the new Crop
  await $(GgcFilterableDropdown).at(1).waitUntilVisible().tap();
  await $(testCropName).tap();                                                     // ### FAILURE OCCURS HERE ###//
  // Create a new Variety for that crop
  await $(CreateButton).at(1).tap();
  expect($(CreateVarietyScreen).visible, equals(true));
  await $(CropDropdown).tap();
  await $(testCropName).tap();
  await $(VarietyNameField).enterText(testVarietyName);
  await $(FormButtons).$('Submit').tap();
  expect($(CreatePlantingScreen).visible, equals(true));
  // Go back to a screen with a drawer
  await $(BackButton).tap();
  await $(BackButton).tap();
  // Now delete the Variety
  await gotoDrawerScreen($, AdminScreen);
  await $(SelectScreenTile).$('Entity Management').tap();
  await $(SelectScreenTile).$('Manage Varieties').tap();
  await $(GgcFilterableDropdown).tap();
  await $(testCropName).tap();
  await $(GgcDropdown).tap();
  await $(testVarietyName).tap();
  await $('Update').tap();
  expect($(UpdateVarietyScreen).visible, equals(true));
  await $(Icons.delete).tap();
  await $('Delete').tap();
  await gotoDrawerScreen($, VarietyIndexScreen);
  // Delete crop
  await gotoDrawerScreen($, AdminScreen);
  await $(SelectScreenTile).$('Entity Management').tap();
  await $(SelectScreenTile).$('Manage Crops').tap();
  await $(CropDropdown).tap();
  await $(testCropName).tap();
  await $('Update').tap();
  await $(Icons.delete).tap();
  await $('Delete').tap();
  await gotoDrawerScreen($, CropIndexScreen);
}

If I incorporate this test into my test suite, it passes sometimes and fails other times. In all cases, the failure occurs on the line marked // ### FAILURE OCCURS HERE ### ///. The failure message is:

The following WaitUntilVisibleTimeoutException was thrown running a test:
TimeoutException after 0:00:10.000000: Finder "Found 0 widgets with text "AAPlantCrop": []" did not
find any visible (i.e. hit-testable) widgets

When the test fails, it's because the previous line with the following Patrol Finder command doesn't result in the dropdown menu items appearing:

  await $(GgcFilterableDropdown).at(1).waitUntilVisible().tap();

However, when the test passes, it's because the above line works as desired.

I have made a YouTube video which shows the results of repeated invocation:

https://www.youtube.com/watch?v=y-83IY7XdKk

Skip to the following spots to see the results for 5 runs in a row. No changes between runs:

• 02:04 Pass
• 09:35 Failure
• 12:11 Pass
• 14:25 Pass
• 15:57 Failure

I don't know how to proceed to figure out what the problem is and how to fix it.

Thank you so much for any help you can provide.