Migration guide

Tests that relied on dirty state from a previously run
test must be updated. For example, the following test,
from packages/flutter/test/material/text_field_test.dart
in the 'Controller can update server' test,
previously passed because of a combination of dirty state
from previous tests and a failure to actually set state
in cases where it should have been set.

Code before migration:

In a widgetsTest, before actually changing text on a
text editing widget, this call might have succeeded:

expect

tester

testTextInput

editingState

'text'

],

isEmpty

);

Code after migration:

Either remove the call entirely, or consider using the
following to assert that the state hasn’t been modified yet:

expect

tester

testTextInput