Make renderAsState public, make WorkflowContainer take a ViewEnvironment.

core-compose/api/core-compose.api

@@ -31,28 +31,31 @@ public final class com/squareup/workflow/ui/compose/CompositionRootKt {
 	public static final fun withCompositionRoot (Lcom/squareup/workflow/ui/ViewRegistry;Lkotlin/jvm/functions/Function2;)Lcom/squareup/workflow/ui/ViewRegistry;
 }
 
+public final class com/squareup/workflow/ui/compose/RenderAsStateKt {
+	public static final fun renderAsState (Lcom/squareup/workflow/Workflow;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;)Landroidx/compose/State;
+	public static final fun renderAsState (Lcom/squareup/workflow/Workflow;Ljava/lang/Object;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;)Landroidx/compose/State;
+	public static final fun renderAsState (Lcom/squareup/workflow/Workflow;Ljava/lang/Object;Lkotlin/jvm/functions/Function1;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;)Landroidx/compose/State;
+	public static final fun renderAsState (Lcom/squareup/workflow/Workflow;Lkotlin/jvm/functions/Function1;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;)Landroidx/compose/State;
+	public static synthetic fun renderAsState$default (Lcom/squareup/workflow/Workflow;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;ILjava/lang/Object;)Landroidx/compose/State;
+	public static synthetic fun renderAsState$default (Lcom/squareup/workflow/Workflow;Ljava/lang/Object;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;ILjava/lang/Object;)Landroidx/compose/State;
+	public static synthetic fun renderAsState$default (Lcom/squareup/workflow/Workflow;Ljava/lang/Object;Lkotlin/jvm/functions/Function1;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;ILjava/lang/Object;)Landroidx/compose/State;
+	public static synthetic fun renderAsState$default (Lcom/squareup/workflow/Workflow;Lkotlin/jvm/functions/Function1;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;ILjava/lang/Object;)Landroidx/compose/State;
+}
+
 public final class com/squareup/workflow/ui/compose/ViewEnvironmentsKt {
 	public static final fun WorkflowRendering (Ljava/lang/Object;Lcom/squareup/workflow/ui/ViewEnvironment;Landroidx/ui/core/Modifier;Landroidx/compose/Composer;)V
 	public static synthetic fun WorkflowRendering$default (Ljava/lang/Object;Lcom/squareup/workflow/ui/ViewEnvironment;Landroidx/ui/core/Modifier;Landroidx/compose/Composer;ILjava/lang/Object;)V
 }
 
 public final class com/squareup/workflow/ui/compose/WorkflowContainerKt {
-	public static final fun WorkflowContainer (Lcom/squareup/workflow/Workflow;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Lkotlin/jvm/functions/Function2;Landroidx/compose/Composer;)V
 	public static final fun WorkflowContainer (Lcom/squareup/workflow/Workflow;Lcom/squareup/workflow/ui/ViewEnvironment;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;)V
-	public static final fun WorkflowContainer (Lcom/squareup/workflow/Workflow;Lcom/squareup/workflow/ui/ViewEnvironment;Ljava/lang/Object;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;)V
-	public static final fun WorkflowContainer (Lcom/squareup/workflow/Workflow;Lcom/squareup/workflow/ui/ViewEnvironment;Ljava/lang/Object;Lkotlin/jvm/functions/Function1;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;)V
-	public static final fun WorkflowContainer (Lcom/squareup/workflow/Workflow;Lcom/squareup/workflow/ui/ViewEnvironment;Lkotlin/jvm/functions/Function1;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;)V
-	public static final fun WorkflowContainer (Lcom/squareup/workflow/Workflow;Ljava/lang/Object;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Lkotlin/jvm/functions/Function2;Landroidx/compose/Composer;)V
-	public static final fun WorkflowContainer (Lcom/squareup/workflow/Workflow;Ljava/lang/Object;Lkotlin/jvm/functions/Function1;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Lkotlin/jvm/functions/Function2;Landroidx/compose/Composer;)V
-	public static final fun WorkflowContainer (Lcom/squareup/workflow/Workflow;Lkotlin/jvm/functions/Function1;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Lkotlin/jvm/functions/Function2;Landroidx/compose/Composer;)V
-	public static synthetic fun WorkflowContainer$default (Lcom/squareup/workflow/Workflow;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Lkotlin/jvm/functions/Function2;Landroidx/compose/Composer;ILjava/lang/Object;)V
+	public static final fun WorkflowContainer (Lcom/squareup/workflow/Workflow;Ljava/lang/Object;Lcom/squareup/workflow/ui/ViewEnvironment;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;)V
+	public static final fun WorkflowContainer (Lcom/squareup/workflow/Workflow;Ljava/lang/Object;Lkotlin/jvm/functions/Function1;Lcom/squareup/workflow/ui/ViewEnvironment;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;)V
+	public static final fun WorkflowContainer (Lcom/squareup/workflow/Workflow;Lkotlin/jvm/functions/Function1;Lcom/squareup/workflow/ui/ViewEnvironment;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;)V
 	public static synthetic fun WorkflowContainer$default (Lcom/squareup/workflow/Workflow;Lcom/squareup/workflow/ui/ViewEnvironment;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;ILjava/lang/Object;)V
-	public static synthetic fun WorkflowContainer$default (Lcom/squareup/workflow/Workflow;Lcom/squareup/workflow/ui/ViewEnvironment;Ljava/lang/Object;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;ILjava/lang/Object;)V
-	public static synthetic fun WorkflowContainer$default (Lcom/squareup/workflow/Workflow;Lcom/squareup/workflow/ui/ViewEnvironment;Ljava/lang/Object;Lkotlin/jvm/functions/Function1;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;ILjava/lang/Object;)V
-	public static synthetic fun WorkflowContainer$default (Lcom/squareup/workflow/Workflow;Lcom/squareup/workflow/ui/ViewEnvironment;Lkotlin/jvm/functions/Function1;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;ILjava/lang/Object;)V
-	public static synthetic fun WorkflowContainer$default (Lcom/squareup/workflow/Workflow;Ljava/lang/Object;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Lkotlin/jvm/functions/Function2;Landroidx/compose/Composer;ILjava/lang/Object;)V
-	public static synthetic fun WorkflowContainer$default (Lcom/squareup/workflow/Workflow;Ljava/lang/Object;Lkotlin/jvm/functions/Function1;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Lkotlin/jvm/functions/Function2;Landroidx/compose/Composer;ILjava/lang/Object;)V
-	public static synthetic fun WorkflowContainer$default (Lcom/squareup/workflow/Workflow;Lkotlin/jvm/functions/Function1;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Lkotlin/jvm/functions/Function2;Landroidx/compose/Composer;ILjava/lang/Object;)V
+	public static synthetic fun WorkflowContainer$default (Lcom/squareup/workflow/Workflow;Ljava/lang/Object;Lcom/squareup/workflow/ui/ViewEnvironment;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;ILjava/lang/Object;)V
+	public static synthetic fun WorkflowContainer$default (Lcom/squareup/workflow/Workflow;Ljava/lang/Object;Lkotlin/jvm/functions/Function1;Lcom/squareup/workflow/ui/ViewEnvironment;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;ILjava/lang/Object;)V
+	public static synthetic fun WorkflowContainer$default (Lcom/squareup/workflow/Workflow;Lkotlin/jvm/functions/Function1;Lcom/squareup/workflow/ui/ViewEnvironment;Landroidx/ui/core/Modifier;Lcom/squareup/workflow/diagnostic/WorkflowDiagnosticListener;Landroidx/compose/Composer;ILjava/lang/Object;)V
 }
 
 public final class com/squareup/workflow/ui/compose/internal/ComposeSupportKt {

core-compose/src/androidTest/java/com/squareup/workflow/ui/compose/RenderAsStateTest.kt

@@ -0,0 +1,234 @@
+/*
+ * Copyright 2020 Square Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+@file:Suppress("RemoveEmptyParenthesesFromAnnotationEntry")
+
+package com.squareup.workflow.ui.compose
+
+import androidx.compose.FrameManager
+import androidx.compose.Providers
+import androidx.compose.mutableStateOf
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.ui.savedinstancestate.UiSavedStateRegistry
+import androidx.ui.savedinstancestate.UiSavedStateRegistryAmbient
+import androidx.ui.test.createComposeRule
+import androidx.ui.test.runOnIdleCompose
+import androidx.ui.test.waitForIdle
+import com.google.common.truth.Truth.assertThat
+import com.squareup.workflow.RenderContext
+import com.squareup.workflow.Snapshot
+import com.squareup.workflow.StatefulWorkflow
+import com.squareup.workflow.Workflow
+import com.squareup.workflow.action
+import com.squareup.workflow.parse
+import com.squareup.workflow.readUtf8WithLength
+import com.squareup.workflow.stateless
+import com.squareup.workflow.ui.compose.RenderAsStateTest.SnapshottingWorkflow.SnapshottedRendering
+import com.squareup.workflow.writeUtf8WithLength
+import okio.ByteString
+import okio.ByteString.Companion.decodeBase64
+import org.junit.Rule
+import org.junit.Test
+import org.junit.runner.RunWith
+
+@RunWith(AndroidJUnit4::class)
+class RenderAsStateTest {
+
+  @Rule @JvmField val composeRule = createComposeRule()
+
+  @Test fun passesPropsThrough() {
+    val workflow = Workflow.stateless<String, Nothing, String> { it }
+    lateinit var initialRendering: String
+
+    composeRule.setContent {
+      initialRendering = workflow.renderAsState("foo").value
+    }
+
+    runOnIdleCompose {
+      assertThat(initialRendering).isEqualTo("foo")
+    }
+  }
+
+  @Test fun seesPropsAndRenderingUpdates() {
+    val workflow = Workflow.stateless<String, Nothing, String> { it }
+    val props = mutableStateOf("foo")
+    lateinit var rendering: String
+
+    composeRule.setContent {
+      rendering = workflow.renderAsState(props.value).value
+    }
+
+    waitForIdle()
+    assertThat(rendering).isEqualTo("foo")
+    FrameManager.framed {
+      props.value = "bar"
+    }
+    waitForIdle()
+    assertThat(rendering).isEqualTo("bar")
+  }
+
+  @Test fun invokesOutputCallback() {
+    val workflow = Workflow.stateless<Unit, String, (String) -> Unit> {
+      { string -> actionSink.send(action { setOutput(string) }) }
+    }
+    val receivedOutputs = mutableListOf<String>()
+    lateinit var rendering: (String) -> Unit
+
+    composeRule.setContent {
+      rendering = workflow.renderAsState(onOutput = { receivedOutputs += it }).value
+    }
+
+    waitForIdle()
+    assertThat(receivedOutputs).isEmpty()
+    rendering("one")
+
+    waitForIdle()
+    assertThat(receivedOutputs).isEqualTo(listOf("one"))
+    rendering("two")
+
+    waitForIdle()
+    assertThat(receivedOutputs).isEqualTo(listOf("one", "two"))
+  }
+
+  @Test fun savesSnapshot() {
+    val workflow = SnapshottingWorkflow()
+    val savedStateRegistry = UiSavedStateRegistry(emptyMap()) { true }
+    lateinit var rendering: SnapshottedRendering
+
+    composeRule.setContent {
+      Providers(UiSavedStateRegistryAmbient provides savedStateRegistry) {
+        rendering = renderAsStateImpl(
+            workflow,
+            props = Unit,
+            onOutput = {},
+            diagnosticListener = null,
+            snapshotKey = SNAPSHOT_KEY
+        ).value
+      }
+    }
+
+    waitForIdle()
+    assertThat(rendering.string).isEmpty()
+    rendering.updateString("foo")
+
+    waitForIdle()
+    val savedValues = FrameManager.framed {
+      savedStateRegistry.performSave()
+    }
+    println("saved keys: ${savedValues.keys}")
+    // Relying on the int key across all runtimes is brittle, so use an explicit key.
+    val snapshot = ByteString.of(*(savedValues.getValue(SNAPSHOT_KEY) as ByteArray))
+    println("snapshot: ${snapshot.base64()}")
+    assertThat(snapshot).isEqualTo(EXPECTED_SNAPSHOT)
+  }
+
+  @Test fun restoresSnapshot() {
+    val workflow = SnapshottingWorkflow()
+    val restoreValues = mapOf(SNAPSHOT_KEY to EXPECTED_SNAPSHOT.toByteArray())
+    val savedStateRegistry = UiSavedStateRegistry(restoreValues) { true }
+    lateinit var rendering: SnapshottedRendering
+
+    composeRule.setContent {
+      Providers(UiSavedStateRegistryAmbient provides savedStateRegistry) {
+        rendering = renderAsStateImpl(
+            workflow,
+            props = Unit,
+            onOutput = {},
+            diagnosticListener = null,
+            snapshotKey = "workflow-snapshot"
+        ).value
+      }
+    }
+
+    waitForIdle()
+    assertThat(rendering.string).isEqualTo("foo")
+  }
+
+  @Test fun restoresFromSnapshotWhenWorkflowChanged() {
+    val workflow1 = SnapshottingWorkflow()
+    val workflow2 = SnapshottingWorkflow()
+    val currentWorkflow = mutableStateOf(workflow1)
+    lateinit var rendering: SnapshottedRendering
+
+    var compositionCount = 0
+    var lastCompositionCount = 0
+    fun assertWasRecomposed() {
+      assertThat(compositionCount).isGreaterThan(lastCompositionCount)
+      lastCompositionCount = compositionCount
+    }
+
+    composeRule.setContent {
+      compositionCount++
+      rendering = currentWorkflow.value.renderAsState().value
+    }
+
+    // Initialize the first workflow.
+    waitForIdle()
+    assertThat(rendering.string).isEmpty()
+    assertWasRecomposed()
+    rendering.updateString("one")
+    waitForIdle()
+    assertWasRecomposed()
+    assertThat(rendering.string).isEqualTo("one")
+
+    // Change the workflow instance being rendered. This should restart the runtime, but restore
+    // it from the snapshot.
+    FrameManager.framed {
+      currentWorkflow.value = workflow2
+    }
+
+    waitForIdle()
+    assertWasRecomposed()
+    assertThat(rendering.string).isEqualTo("one")
+  }
+
+  private companion object {
+    const val SNAPSHOT_KEY = "workflow-snapshot"
+
+    /** Golden value from [savesSnapshot]. */
+    val EXPECTED_SNAPSHOT = "AAAABwAAAANmb28AAAAA".decodeBase64()!!
+  }
+
+  // Seems to be a problem accessing Workflow.stateful.
+  private class SnapshottingWorkflow :
+      StatefulWorkflow<Unit, String, Nothing, SnapshottedRendering>() {
+
+    data class SnapshottedRendering(
+      val string: String,
+      val updateString: (String) -> Unit
+    )
+
+    override fun initialState(
+      props: Unit,
+      snapshot: Snapshot?
+    ): String = snapshot?.bytes?.parse { it.readUtf8WithLength() } ?: ""
+
+    override fun render(
+      props: Unit,
+      state: String,
+      context: RenderContext<String, Nothing>
+    ) = SnapshottedRendering(
+        string = state,
+        updateString = { newString -> context.actionSink.send(updateString(newString)) }
+    )
+
+    override fun snapshotState(state: String): Snapshot =
+      Snapshot.write { it.writeUtf8WithLength(state) }
+
+    private fun updateString(newString: String) = action {
+      nextState = newString
+    }
+  }
+}