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Building a Weather Application From Scratch

Unit Testing With Mock Objects

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Earlier in this series, we wrote unit tests for the DayViewModel, the WeekViewModel, and the WeekDayViewModel structs. Writing those unit tests was fairly straightforward. Unit testing the RootViewModel class is a bit more challenging for a number of reasons.

The RootViewModel class asynchronously fetches the location of the device and weather data for a location. To unit test asynchronous operations, we need to take a different approach.

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Next Episode "Unit Testing Asynchronous Code"