985: render() again only if state has been changed by the action (or its parent's output handling)

.github/workflows/kotlin.yml

@@ -188,6 +188,62 @@ jobs :
         with :
           report_paths : '**/build/test-results/test/TEST-*.xml'
 
+  jvm-stateChange-runtime-test :
+    name : Render On State Change Only Runtime JVM Tests
+    runs-on : ubuntu-latest
+    timeout-minutes : 20
+    steps :
+      - uses : actions/checkout@v3
+      - uses : gradle/wrapper-validation-action@v1
+      - name : set up JDK 11
+        uses : actions/setup-java@v3
+        with :
+          distribution : 'zulu'
+          java-version : 11
+
+      ## Actual task
+      - uses : gradle/gradle-build-action@v2
+        name : Check with Gradle
+        with :
+          arguments : |
+            jvmTest --continue -Pworkflow.runtime=baseline-stateChange
+          cache-read-only : false
+
+      # Report as Github Pull Request Check.
+      - name : Publish Test Report
+        uses : mikepenz/action-junit-report@v3
+        if : always() # always run even if the previous step fails
+        with :
+          report_paths : '**/build/test-results/test/TEST-*.xml'
+
+  jvm-conflate-stateChange-runtime-test :
+    name : Render On State Change Only Runtime JVM Tests
+    runs-on : ubuntu-latest
+    timeout-minutes : 20
+    steps :
+      - uses : actions/checkout@v3
+      - uses : gradle/wrapper-validation-action@v1
+      - name : set up JDK 11
+        uses : actions/setup-java@v3
+        with :
+          distribution : 'zulu'
+          java-version : 11
+
+      ## Actual task
+      - uses : gradle/gradle-build-action@v2
+        name : Check with Gradle
+        with :
+          arguments : |
+            jvmTest --continue -Pworkflow.runtime=conflate-stateChange
+          cache-read-only : false
+
+      # Report as Github Pull Request Check.
+      - name : Publish Test Report
+        uses : mikepenz/action-junit-report@v3
+        if : always() # always run even if the previous step fails
+        with :
+          report_paths : '**/build/test-results/test/TEST-*.xml'
+
   ios-tests :
     name : iOS Tests
     runs-on : macos-latest
@@ -280,7 +336,6 @@ jobs :
           profile : Galaxy Nexus
           api-level : ${{ matrix.api-level }}
           arch : x86_64
-          # Skip the benchmarks as this is running on emulators
           script : ./gradlew :benchmarks:performance-poetry:complex-poetry:connectedCheck --continue
 
       - name : Upload results
@@ -384,6 +439,102 @@ jobs :
           name : instrumentation-test-results-${{ matrix.api-level }}
           path : ./**/build/reports/androidTests/connected/**
 
+  stateChange-runtime-instrumentation-tests :
+    name : Render on State Change Only Instrumentation tests
+    runs-on : macos-latest
+    timeout-minutes : 45
+    strategy :
+      # Allow tests to continue on other devices if they fail on one device.
+      fail-fast : false
+      matrix :
+        api-level :
+          - 29
+      # Unclear that older versions actually honor command to disable animation.
+      # Newer versions are reputed to be too slow: https://github.com/ReactiveCircus/android-emulator-runner/issues/222
+    steps :
+      - uses : actions/checkout@v3
+      - name : set up JDK 11
+        uses : actions/setup-java@v3
+        with :
+          distribution : 'zulu'
+          java-version : 11
+
+      ## Build before running tests, using cache.
+      - uses : gradle/gradle-build-action@v2
+        name : Build instrumented tests
+        with :
+          # Unfortunately I don't think we can key this cache based on our project property so
+          # we clean and rebuild.
+          arguments : |
+            clean assembleDebugAndroidTest -Pworkflow.runtime=baseline-stateChange
+          cache-read-only : false
+
+      ## Actual task
+      - name : Instrumentation Tests
+        uses : reactivecircus/android-emulator-runner@v2
+        with :
+          # @ychescale9 suspects Galaxy Nexus is the fastest one
+          profile : Galaxy Nexus
+          api-level : ${{ matrix.api-level }}
+          arch : x86_64
+          # Skip the benchmarks as this is running on emulators
+          script : ./gradlew connectedCheck -x :benchmarks:dungeon-benchmark:connectedCheck -x :benchmarks:performance-poetry:complex-benchmark:connectedCheck -x :benchmarks:performance-poetry:complex-poetry:connectedCheck -Pworkflow.runtime=baseline-stateChange
+
+      - name : Upload results
+        if : ${{ always() }}
+        uses : actions/upload-artifact@v3
+        with :
+          name : instrumentation-test-results-${{ matrix.api-level }}
+          path : ./**/build/reports/androidTests/connected/**
+
+  conflate-stateChange-runtime-instrumentation-tests :
+    name : Render on State Change Only Instrumentation tests
+    runs-on : macos-latest
+    timeout-minutes : 45
+    strategy :
+      # Allow tests to continue on other devices if they fail on one device.
+      fail-fast : false
+      matrix :
+        api-level :
+          - 29
+      # Unclear that older versions actually honor command to disable animation.
+      # Newer versions are reputed to be too slow: https://github.com/ReactiveCircus/android-emulator-runner/issues/222
+    steps :
+      - uses : actions/checkout@v3
+      - name : set up JDK 11
+        uses : actions/setup-java@v3
+        with :
+          distribution : 'zulu'
+          java-version : 11
+
+      ## Build before running tests, using cache.
+      - uses : gradle/gradle-build-action@v2
+        name : Build instrumented tests
+        with :
+          # Unfortunately I don't think we can key this cache based on our project property so
+          # we clean and rebuild.
+          arguments : |
+            clean assembleDebugAndroidTest -Pworkflow.runtime=conflate-stateChange
+          cache-read-only : false
+
+      ## Actual task
+      - name : Instrumentation Tests
+        uses : reactivecircus/android-emulator-runner@v2
+        with :
+          # @ychescale9 suspects Galaxy Nexus is the fastest one
+          profile : Galaxy Nexus
+          api-level : ${{ matrix.api-level }}
+          arch : x86_64
+          # Skip the benchmarks as this is running on emulators
+          script : ./gradlew connectedCheck -x :benchmarks:dungeon-benchmark:connectedCheck -x :benchmarks:performance-poetry:complex-benchmark:connectedCheck -x :benchmarks:performance-poetry:complex-poetry:connectedCheck -Pworkflow.runtime=conflate-stateChange
+
+      - name : Upload results
+        if : ${{ always() }}
+        uses : actions/upload-artifact@v3
+        with :
+          name : instrumentation-test-results-${{ matrix.api-level }}
+          path : ./**/build/reports/androidTests/connected/**
+
   upload-to-mobiledev :
     name : mobile.dev | Build & Upload
     runs-on : ubuntu-latest

benchmarks/performance-poetry/complex-poetry/src/main/java/com/squareup/benchmarks/performance/complex/poetry/PerformancePoetryActivity.kt

@@ -21,7 +21,7 @@ import com.squareup.benchmarks.performance.complex.poetry.instrumentation.Simula
 import com.squareup.sample.container.SampleContainers
 import com.squareup.sample.poetry.model.Poem
 import com.squareup.workflow1.RuntimeConfig
-import com.squareup.workflow1.RuntimeConfig.RenderPerAction
+import com.squareup.workflow1.RuntimeConfigOptions.Companion.RENDER_PER_ACTION
 import com.squareup.workflow1.WorkflowExperimentalRuntime
 import com.squareup.workflow1.WorkflowInterceptor
 import com.squareup.workflow1.ui.Screen
@@ -87,7 +87,7 @@ class PerformancePoetryActivity : AppCompatActivity() {
       installedInterceptor = ActionHandlingTracingInterceptor()
     }
 
-    val runtimeConfig = RenderPerAction
+    val runtimeConfig = RENDER_PER_ACTION
 
     val component =
       PerformancePoetryComponent(installedInterceptor, simulatedPerfConfig, runtimeConfig)

workflow-config/config-android/api/config-android.api

@@ -4,7 +4,7 @@ public final class com/squareup/workflow1/config/AndroidRuntimeConfigTools {
 }
 
 public final class com/squareup/workflow1/config/AndroidRuntimeConfigTools$Companion {
-	public final fun getAppWorkflowRuntimeConfig ()Lcom/squareup/workflow1/RuntimeConfig;
+	public final fun getAppWorkflowRuntimeConfig ()Ljava/util/Set;
 }
 
 public final class com/squareup/workflow1/config/BuildConfig {

workflow-config/config-android/src/main/java/com/squareup/workflow1/config/AndroidRuntimeConfigTools.kt

@@ -1,8 +1,9 @@
 package com.squareup.workflow1.config
 
 import com.squareup.workflow1.RuntimeConfig
-import com.squareup.workflow1.RuntimeConfig.ConflateStaleRenderings
-import com.squareup.workflow1.RuntimeConfig.RenderPerAction
+import com.squareup.workflow1.RuntimeConfigOptions
+import com.squareup.workflow1.RuntimeConfigOptions.CONFLATE_STALE_RENDERINGS
+import com.squareup.workflow1.RuntimeConfigOptions.RENDER_ONLY_WHEN_STATE_CHANGES
 import com.squareup.workflow1.WorkflowExperimentalRuntime
 
 public class AndroidRuntimeConfigTools {
@@ -11,23 +12,34 @@ public class AndroidRuntimeConfigTools {
     /**
      * Helper for Configuration for the workflow runtime in an application.
      * This allows one to specify a project property from the gradle build to choose a runtime.
-     * e.g. add "-Pworkflow.runtime=timeout" in your gradle build to build the timeout runtime into
-     * the application.
+     * e.g. add "-Pworkflow.runtime=conflate" in your gradle build to build the conflate runtime
+     * into the application.
      *
      * Note that this must be specified in the application built for any ui/integration tests. Call
      * this function, and then pass that to the call to [renderWorkflowIn] as the [RuntimeConfig].
      *
      * Current options are:
-     * "conflate" : [ConflateStaleRenderings] Process all queued actions before passing rendering
+     * "conflate" : Process all queued actions before passing rendering
      *      to the UI layer.
-     * "baseline" : [RenderPerAction] Original Workflow Runtime. Note that this doesn't need to
+     * "baseline" : Original Workflow Runtime. Note that this doesn't need to
      *      be specified as it is the current default and is assumed by this utility.
+     *
+     * Then, these can be combined (via '-') with:
+     * "stateChange" : Only re-render when the state of some WorkflowNode has been changed by an
+     *   action cascade.
+     *
+     * E.g., "baseline-stateChange" to turn on the stateChange option with the baseline runtime.
+     *
      */
     @WorkflowExperimentalRuntime
     public fun getAppWorkflowRuntimeConfig(): RuntimeConfig {
       return when (BuildConfig.WORKFLOW_RUNTIME) {
-        "conflate" -> ConflateStaleRenderings
-        else -> RenderPerAction
+        "conflate" -> setOf(CONFLATE_STALE_RENDERINGS)
+        "conflate-stateChange" -> setOf(CONFLATE_STALE_RENDERINGS, RENDER_ONLY_WHEN_STATE_CHANGES)
+        "baseline-stateChange" -> setOf(RENDER_ONLY_WHEN_STATE_CHANGES)
+        "", "baseline" -> RuntimeConfigOptions.RENDER_PER_ACTION
+        else ->
+          throw IllegalArgumentException("Unrecognized config \"${BuildConfig.WORKFLOW_RUNTIME}\"")
       }
     }
   }

workflow-config/config-jvm/api/config-jvm.api

@@ -4,6 +4,6 @@ public final class com/squareup/workflow1/config/JvmTestRuntimeConfigTools {
 }
 
 public final class com/squareup/workflow1/config/JvmTestRuntimeConfigTools$Companion {
-	public final fun getTestRuntimeConfig ()Lcom/squareup/workflow1/RuntimeConfig;
+	public final fun getTestRuntimeConfig ()Ljava/util/Set;
 }
 

workflow-config/config-jvm/src/main/java/com/squareup/workflow1/config/JvmTestRuntimeConfigTools.kt

@@ -1,33 +1,46 @@
 package com.squareup.workflow1.config
 
 import com.squareup.workflow1.RuntimeConfig
-import com.squareup.workflow1.RuntimeConfig.ConflateStaleRenderings
-import com.squareup.workflow1.RuntimeConfig.RenderPerAction
+import com.squareup.workflow1.RuntimeConfigOptions
+import com.squareup.workflow1.RuntimeConfigOptions.CONFLATE_STALE_RENDERINGS
+import com.squareup.workflow1.RuntimeConfigOptions.RENDER_ONLY_WHEN_STATE_CHANGES
 import com.squareup.workflow1.WorkflowExperimentalRuntime
 
 public class JvmTestRuntimeConfigTools {
   public companion object {
     /**
-     * Helper for Configuration for the Workflow Runtime while running tests on the JVM.
+     * Helper for Configuration for the workflow runtime in an application.
      * This allows one to specify a project property from the gradle build to choose a runtime.
-     * e.g. add "-Pworkflow.runtime=timeout" in your gradle build to build the timeout runtime.
+     * e.g. add "-Pworkflow.runtime=conflate" in your gradle build to build the conflate runtime
+     * into the application.
      *
      * The [WorkflowTestRuntime] already calls this utility, but if starting your own runtime, then
      * call this function and pass the result to the call to [renderWorkflowIn] as the
      * [RuntimeConfig].
      *
      * Current options are:
-     * "conflate" : [ConflateStaleRenderings] Process all queued actions before passing rendering
+     * "conflate" : Process all queued actions before passing rendering
      *      to the UI layer.
-     * "baseline" : [RenderPerAction] Original Workflow Runtime. Note that this doesn't need to
+     * "baseline" : Original Workflow Runtime. Note that this doesn't need to
      *      be specified as it is the current default and is assumed by this utility.
+     *
+     * Then, these can be combined (via '-') with:
+     * "stateChange" : Only re-render when the state of some WorkflowNode has been changed by an
+     *   action cascade.
+     *
+     * E.g., "baseline-stateChange" to turn on the stateChange option with the baseline runtime.
+     *
      */
     @OptIn(WorkflowExperimentalRuntime::class)
     public fun getTestRuntimeConfig(): RuntimeConfig {
-      val runtimeConfig = System.getProperty("workflow.runtime", "baseline")
-      return when (runtimeConfig) {
-        "conflate" -> ConflateStaleRenderings
-        else -> RenderPerAction
+      return when
+      (val runtimeConfig = System.getProperty("workflow.runtime", "baseline")) {
+        "conflate" -> setOf(CONFLATE_STALE_RENDERINGS)
+        "conflate-stateChange" -> setOf(CONFLATE_STALE_RENDERINGS, RENDER_ONLY_WHEN_STATE_CHANGES)
+        "baseline-stateChange" -> setOf(RENDER_ONLY_WHEN_STATE_CHANGES)
+        "", "baseline" -> RuntimeConfigOptions.RENDER_PER_ACTION
+        else ->
+          throw IllegalArgumentException("Unrecognized config \"$runtimeConfig\"")
       }
     }
   }

workflow-core/api/workflow-core.api

@@ -1,3 +1,17 @@
+public final class com/squareup/workflow1/ActionApplied : com/squareup/workflow1/ActionProcessingResult {
+	public fun <init> (Lcom/squareup/workflow1/WorkflowOutput;Z)V
+	public synthetic fun <init> (Lcom/squareup/workflow1/WorkflowOutput;ZILkotlin/jvm/internal/DefaultConstructorMarker;)V
+	public final fun component1 ()Lcom/squareup/workflow1/WorkflowOutput;
+	public final fun component2 ()Z
+	public final fun copy (Lcom/squareup/workflow1/WorkflowOutput;Z)Lcom/squareup/workflow1/ActionApplied;
+	public static synthetic fun copy$default (Lcom/squareup/workflow1/ActionApplied;Lcom/squareup/workflow1/WorkflowOutput;ZILjava/lang/Object;)Lcom/squareup/workflow1/ActionApplied;
+	public fun equals (Ljava/lang/Object;)Z
+	public final fun getOutput ()Lcom/squareup/workflow1/WorkflowOutput;
+	public final fun getStateChanged ()Z
+	public fun hashCode ()I
+	public fun toString ()Ljava/lang/String;
+}
+
 public abstract interface class com/squareup/workflow1/ActionProcessingResult {
 }
 
@@ -271,7 +285,7 @@ public final class com/squareup/workflow1/WorkflowIdentifierType$Unsnapshottable
 	public fun toString ()Ljava/lang/String;
 }
 
-public final class com/squareup/workflow1/WorkflowOutput : com/squareup/workflow1/ActionProcessingResult {
+public final class com/squareup/workflow1/WorkflowOutput {
 	public fun <init> (Ljava/lang/Object;)V
 	public fun equals (Ljava/lang/Object;)Z
 	public final fun getValue ()Ljava/lang/Object;