PlayMode and unit testing a player health bar with events, logging, and exceptions

In this recipe, we will combine many different kinds of tests for a feature that’s included in many games – a visual health bar representing the player’s numeric health value (in this case, a float number from 0.0 to 1.0). Although it doesn’t comprehensively test all aspects of the health bar, this recipe will provide a good example of how we can go about testing many different parts of a game using the Unity testing tools.

A Unity package has been provided that contains the following:

• Player.cs: A player script class for managing values for player health that uses delegates and events to publish health changes to any listening View classes.
• Two View classes that register to listen for player health change events:
  • HealthBarDisplay.cs: This updates fillAmount for a UI image for each new player health value that’s received.
  • HealthChangeLogger...