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Unit tests

A unit test tests a single function, method, or class.
The goal of a unit test is to verify the correctness of a
unit of logic under a variety of conditions.
External dependencies of the unit under test are generally
mocked out.
Unit tests generally don’t read from or write
to disk, render to screen, or receive user actions from
outside the process running the test.
For more information regarding unit tests, 
you can view the following recipes 
or run flutter test --help in your terminal.

Note:
  If you’re writing unit tests for code that
  uses plugins and you want to avoid crashes,
  check out Plugins in Flutter tests.
  If you want to test your Flutter plugin,
  check out Testing plugins.

Recipes

An introduction to unit testing

Mock dependencies using Mockito

Widget tests