Learn why some PCF methods are impossible to test while others achieve 100% test coverage—and how to write testable PCF methods from the start. This in-depth comparison of isInDesignMode() and isAuthoringMode() reveals the critical difference between global state dependencies and dependency injection in Power Apps Component Framework development. Discover why JSDOM's limitations make browser global access untestable, how to leverage PCF context properties for reliable unit tests with Jest, and the design principles that separate maintainable code from technical debt. With real test results showing 5 passing tests versus skipped placeholders, you'll understand exactly how dependency injection transforms PCF code quality. Perfect for developers building enterprise-grade PCF controls who value comprehensive test coverage and sustainable code architecture.
