dispatch-test-junit4

#features
#setting-dispatchersmain
#this-module-replaces-dispatch-test
#junit-dependencies

#minimum-gradle-config
#junit-5-interoperability

Features

In addition to all the functionality in dispatch-test, this module exposes a TestCoroutineRule to handle set-up and tear-down of a TestProvidedCoroutineScope.

Since TestProvidedCoroutineScope is a TestCoroutineScope, this Rule also invokes cleanupTestCoroutines after the test.

class SomeClassTest {

  @JvmField
  @Rule
  val rule = TestCoroutineRule()

  @Test
  fun `some test`() = runBlocking {

    val subject = SomeClass(rule)

    val job = subject.fireAndForget()

    // TODO: assertions go here
  }

}

class SomeClass(val coroutineScope: CoroutineScope) {
  fun fireAndForget() = launch { }
}

Setting Dispatchers.Main

Even though dispatch-core eliminates the need to use Dispatchers.Main in internal code, it’s still possible that code which has yet to be migrated, or a third-party library is making use of the hard-coded dispatcher. Because of this, the rule still calls Dispatchers.setMain(...) in its setup and Dispatchers.resetMain() afterwards.

This module replaces dispatch-test

If using this module, there is no need to include the dispatch-test artifact in your dependencies.

JUnit dependencies

Minimum Gradle Config

Because this is a JUnit 4 Rule, it requires a variant of that artifact. No external libraries are bundled as part of Dispatch, so you’ll need to add it to your dependencies block yourself. The two official options would be:

classic JUnit 4

org.junit.jupiter:junit-jupiter:4.13

JUnit 5 "vintage"

org.junit.vintage:junit-vintage-engine:5.5.1

Add to your module's build.gradle.kts:

repositories {
  mavenCentral()
}

dependencies {

  // core
  implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.5.0")
  implementation("org.jetbrains.kotlinx:kotlinx-coroutines-android:1.5.0")
  implementation(platform("com.rickbusarow.dispatch:dispatch-bom:1.0.0-beta10"))
  implementation("com.rickbusarow.dispatch:dispatch-core")

  // the junit4 artifact also provides the dispatch-test artifact
  testImplementation("com.rickbusarow.dispatch:dispatch-test-junit4")
  testImplementation("org.jetbrains.kotlinx:kotlinx-coroutines-test:1.5.0")
}

JUnit 5 interoperability

Junit 5 provides a “vintage” (JUnit 4) artifact for legacy support (such as Robolectric or Android instrumented tests). Dispatch also supports running both in the same project by just adding both artifacts.