existsOnce method

WidgetMatcher<W> existsOnce()

Asserts that exactly one widget of type W exists.

Example usage:

spot<ElevatedButton>().existsOnce();

See also:

• doesNotExist asserts that no widgets of type W exist.
• existsExactlyNTimes asserts that exactly n widgets of type W exist.
• existsAtLeastOnce asserts that at least one widget of type W exists.
• existsAtLeastNTimes asserts that at least n widgets of type W exist.
• existsAtMostOnce asserts that at most one widget exists.
• existsAtMostNTimes asserts that at most n widgets of type W exist.

Implementation

WidgetMatcher<W> existsOnce() {
  final one =
      copyWith(quantityConstraint: const QuantityConstraint.exactly(1));
  return snapshot(one).single;
}