Test-Driven Development and Unit TestingUsing JestCreating an Example Module to TestAnatomy of a Test CaseArrangeAct AssertUsing TDDRefactoring CodeEvaluating Test CoverageReplacing Dependencies with Fakes, Stubs, and MocksCreating a Module with DependenciesCreating a Doubles FolderUsing a StubUsing a FakeUsing a MockAdditional Types of TestsFunctional TestsIntegration TestsEnd-to-End TestsSnapshot TestsExercise 8: Add Test Cases to the Weather AppTesting the Middleware with SpiesCreating Mocks to Test the ServicesPerforming an End-to-End Test of the REST APIEvaluating the User Interface with a Snapshot TestSummary