setting-up-host-vs-device-tests

What problem does it solve?

It helps you decide whether a Jetpack Compose test should run on the host (Robolectric/JVM) or on a real/virtual device (instrumentation), and then configure it so key capabilities actually work.

Core Features & Use Cases

• Host vs device selection: Use src/test/ (host) for fast logic/recomposition/finder-style assertions, and src/androidTest/ (device) for RenderThread-dependent behavior.
• Correct source-set placement: Organize tests so screenshot capture, ripple/Modifier.indication rendering, and accessibility checks run in the right flavor.
• Robolectric host skeleton & guardrails: Apply the canonical @RunWith(AndroidJUnit4::class) and @Config(minSdk = 23) setup and enforce clock-driven determinism.
• Legitimate Thread.sleep only for RenderThread: Replace Thread.sleep in host tests entirely, and allow it in device tests only as a RenderThread waiting mechanism for screenshot/golden assertions.

Quick Start

Tell the AI: “I have a Jetpack Compose test that passes locally but fails on CI—should it go in src/test or src/androidTest, and what setup do I need?”