Make side effect expectations explicit requirement.

workflow-testing/api/workflow-testing.api

@@ -20,6 +20,7 @@ public abstract class com/squareup/workflow1/testing/RenderTester {
 	public static synthetic fun expectSideEffect$default (Lcom/squareup/workflow1/testing/RenderTester;Ljava/lang/String;ZLkotlin/jvm/functions/Function1;ILjava/lang/Object;)Lcom/squareup/workflow1/testing/RenderTester;
 	public abstract fun render (Lkotlin/jvm/functions/Function1;)Lcom/squareup/workflow1/testing/RenderTestResult;
 	public static synthetic fun render$default (Lcom/squareup/workflow1/testing/RenderTester;Lkotlin/jvm/functions/Function1;ILjava/lang/Object;)Lcom/squareup/workflow1/testing/RenderTestResult;
+	public abstract fun requireExplicitSideEffectExpectations ()Lcom/squareup/workflow1/testing/RenderTester;
 	public abstract fun requireExplicitWorkerExpectations ()Lcom/squareup/workflow1/testing/RenderTester;
 }
 

workflow-testing/src/main/java/com/squareup/workflow1/testing/RealRenderTester.kt

@@ -98,6 +98,7 @@ internal class RealRenderTester<PropsT, StateT, OutputT, RenderingT>(
   }
 
   private var explicitWorkerExpectationsRequired: Boolean = false
+  private var explicitSideEffectExpectationsRequired: Boolean = false
   override val actionSink: Sink<WorkflowAction<PropsT, StateT, OutputT>> get() = this
 
   override fun expectWorkflow(
@@ -125,6 +126,11 @@ internal class RealRenderTester<PropsT, StateT, OutputT, RenderingT>(
       expectWorker(description = "unexpected worker", exactMatch = false) { _, _, _ -> true }
     }
 
+    if (!explicitSideEffectExpectationsRequired) {
+      // Allow unexpected side effects.
+      expectSideEffect(description = "unexpected side effect", exactMatch = false) { true }
+    }
+
     // Clone the expectations to run a "dry" render pass.
     val noopContext = deepCloneForRender()
     workflow.render(props, state, RenderContext(noopContext, workflow))
@@ -251,6 +257,11 @@ internal class RealRenderTester<PropsT, StateT, OutputT, RenderingT>(
     explicitWorkerExpectationsRequired = true
   }
 
+  override fun requireExplicitSideEffectExpectations():
+    RenderTester<PropsT, StateT, OutputT, RenderingT> = this.apply {
+    explicitSideEffectExpectationsRequired = true
+  }
+
   override fun send(value: WorkflowAction<PropsT, StateT, OutputT>) {
     checkNoOutputs()
     check(processedAction == null) {

workflow-testing/src/main/java/com/squareup/workflow1/testing/RenderTester.kt

@@ -244,6 +244,9 @@ public abstract class RenderTester<PropsT, StateT, OutputT, RenderingT> {
   public abstract fun requireExplicitWorkerExpectations():
     RenderTester<PropsT, StateT, OutputT, RenderingT>
 
+  public abstract fun requireExplicitSideEffectExpectations():
+    RenderTester<PropsT, StateT, OutputT, RenderingT>
+
   /**
    * Describes a call to
    * [RenderContext.renderChild][com.squareup.workflow1.BaseRenderContext.renderChild].

workflow-testing/src/test/java/com/squareup/workflow1/testing/RealRenderTesterTest.kt

@@ -106,6 +106,7 @@ internal class RealRenderTesterTest {
       runningSideEffect("the key") {}
     }
     val tester = workflow.testRender(Unit)
+      .requireExplicitSideEffectExpectations()
       .expectSideEffect(key = "the key")
       .expectSideEffect(description = "duplicate match") { it == "the key" }
 
@@ -326,7 +327,7 @@ internal class RealRenderTesterTest {
     val workflow = Workflow.stateless<Unit, Nothing, Unit> {
       runningSideEffect("effect") {}
     }
-    val tester = workflow.testRender(Unit)
+    val tester = workflow.testRender(Unit).requireExplicitSideEffectExpectations()
 
     val error = assertFailsWith<AssertionError> {
       tester.render()
@@ -340,6 +341,7 @@ internal class RealRenderTesterTest {
       runningSideEffect("unexpected") {}
     }
     val tester = workflow.testRender(Unit)
+      .requireExplicitSideEffectExpectations()
       .expectSideEffect("expected")
 
     val error = assertFailsWith<AssertionError> {
@@ -353,6 +355,7 @@ internal class RealRenderTesterTest {
       runningSideEffect("effect") {}
     }
     val tester = workflow.testRender(Unit)
+      .requireExplicitSideEffectExpectations()
       .expectSideEffect("effect")
       .expectSideEffect(description = "custom", exactMatch = true) { key -> "effect" in key }
 
@@ -546,6 +549,30 @@ internal class RealRenderTesterTest {
     tester.render()
   }
 
+  @Test fun `runningSideEffect doesn't throw when none expected`() {
+    val workflow = Workflow.stateless<Unit, Nothing, Unit> {
+      runningSideEffect(key = "foo") { }
+    }
+    val tester = workflow.testRender(Unit)
+    tester.render()
+  }
+
+  @Test fun `runningSideEffect does throw when none expected and require explicit side effect is set`() { // ktlint-disable max-line-length
+    val key = "foo"
+    val workflow = Workflow.stateless<Unit, Nothing, Unit> {
+      runningSideEffect(key = key) { }
+    }
+    val tester = workflow.testRender(Unit).requireExplicitSideEffectExpectations()
+    val error = assertFailsWith<AssertionError> {
+      tester.render()
+    }
+
+    assertEquals(
+      "Tried to run unexpected side effect with key \"$key\"",
+      error.message
+    )
+  }
+
   @Test fun `runningWorker does throw when none expected and require explicit workers is set`() {
     class MySpecialWorker : Worker<Nothing> {
       override fun doesSameWorkAs(otherWorker: Worker<*>): Boolean = true