Merge pull request #8 from yahoo/sal/debugstrings

Usability fixes and fix reflection on Android

behavior-graph/build.gradle

@@ -47,7 +47,7 @@ publishing {
             from components.java
             groupId = 'com.yahoo.behaviorgraph'
             artifactId = 'bgjvm'
-            version = '0.7.0'
+            version = '0.8.0'
             artifact dokkaJavadocJar
             repositories {
 

behavior-graph/src/main/kotlin/behaviorgraph/Behavior.kt

@@ -47,7 +47,20 @@ class Behavior<T: Any>(
     }
 
     override fun toString(): String {
-        return "Behavior()"
+        var rows = mutableListOf<String>("Behavior")
+        supplies?.forEachIndexed { index, resource ->
+            if (index == 0) {
+                rows.add(" Supplies:")
+            }
+            rows.add("  " + resource.toString())
+        }
+        demands?.forEachIndexed { index, resource ->
+            if (index == 0) {
+                rows.add(" Demands:")
+            }
+            rows.add("  " + resource.toString())
+        }
+        return rows.joinToString("\n")
     }
 
     /**

behavior-graph/src/main/kotlin/behaviorgraph/BehaviorBuilder.kt

@@ -122,6 +122,12 @@ class BehaviorBuilder<T: Any>(
         dynamicSupplyRelinkingOrder = relinkingOrder
     }
 
+    /**
+     * Alternate form of `runs` for Kotlin because `.run()` is a builtin scope function
+     * and is easily confused with Behavior Graph's `.runs()`.
+     */
+    fun performs(thunk: ExtentThunk<T>): Behavior<T> = runs(thunk)
+
     /**
      * Required clause which sets the block of code the behavior will run when one or more of its demands are updated.
      * The `ext` parameter passed in when the behavior is run is the [Extent] instance this behavior was created on.

behavior-graph/src/main/kotlin/behaviorgraph/EventLoopState.kt

@@ -1,3 +1,11 @@
 package behaviorgraph
 
-internal data class EventLoopState(val action: RunnableAction, val actionUpdates: MutableList<Resource> = mutableListOf(), var currentSideEffect: SideEffect? = null, var phase: EventLoopPhase = EventLoopPhase.Queued)
+internal data class EventLoopState(val action: RunnableAction, val actionUpdates: MutableList<Resource> = mutableListOf(), var currentSideEffect: SideEffect? = null, var phase: EventLoopPhase = EventLoopPhase.Queued) {
+    override fun toString(): String {
+        var rows = mutableListOf<String>("Action")
+        actionUpdates?.forEach { resource ->
+            rows.add("  " + resource.toString())
+        }
+        return rows.joinToString("\n")
+    }
+}

behavior-graph/src/main/kotlin/behaviorgraph/Extent.kt

@@ -48,6 +48,7 @@ open class Extent<ExtentContext: Any> @JvmOverloads constructor(val graph: Graph
     val didAdd: State<Boolean> = State(this, false)
 
     init {
+        didAdd.debugName = "_didAdd_"
         didAddBehavior = behavior().supplies(didAdd).runs { this.didAdd.update(true) }
     }
 
@@ -148,17 +149,21 @@ open class Extent<ExtentContext: Any> @JvmOverloads constructor(val graph: Graph
     private fun nameResources() {
         // context object or this extent if none
         val focus: Any = context ?: this
-        focus.javaClass.declaredFields.forEach { field ->
-            // iterate through each field and see if its a resource subclass
-            if ((Resource::class.java as Class).isAssignableFrom(field.type)) {
-                // sometimes fields aren't accessible to reflection, try enabling that
-                if (field.trySetAccessible()) {
+        try {
+            focus.javaClass.declaredFields.forEach { field ->
+                // iterate through each field and see if its a resource subclass
+                if ((Resource::class.java as Class).isAssignableFrom(field.type)) {
+                    // sometimes fields aren't accessible to reflection, try enabling that
+                    field.isAccessible = true // throws error if not possible
                     val resource = field.get(focus) as Resource
                     if (resource.debugName == null) {
                         resource.debugName = field.name
                     }
                 }
             }
+        } catch (ex: Exception) {
+            // throws error if we cannot make fields accessible for security reasons
+            // catching the error is fine here, it just means we won't get debug names
         }
     }
 
@@ -227,4 +232,9 @@ open class Extent<ExtentContext: Any> @JvmOverloads constructor(val graph: Graph
         val action = ExtentAction(thunk, (context ?: this) as ExtentContext, debugName)
         graph.actionHelper(action)
     }
+
+    override fun toString(): String {
+        return graph.toString()
+    }
+
 }

behavior-graph/src/main/kotlin/behaviorgraph/Graph.kt

@@ -693,4 +693,21 @@ class Graph @JvmOverloads constructor(private val dateProvider: DateProvider? =
         }
         extent.addedToGraphWhen = null
     }
+
+    override fun toString(): String {
+        return buildString {
+            if (currentEvent != null) {
+                append(String.format("Current Event: %d\n", currentEvent!!.sequence))
+            } else {
+                append("No current event")
+            }
+            if (eventLoopState != null) {
+                append(eventLoopState!!.toString())
+                append("\n")
+            }
+            if (currentBehavior != null) {
+                append(currentBehavior!!.toString())
+            }
+        }
+    }
 }

behavior-graph/src/main/kotlin/behaviorgraph/Moment.kt

@@ -61,4 +61,8 @@ class Moment @JvmOverloads constructor(extent: Extent<*>, debugName: String? = n
         _happened = false
     }
 
+    override fun toString(): String {
+        return String.format("%s (m) == %s (%s)", debugName ?: "resource", if (_happened) "Updated" else "Not Updated", event?.sequence)
+    }
+
 }

behavior-graph/src/main/kotlin/behaviorgraph/Resource.kt

@@ -52,4 +52,8 @@ open class Resource @JvmOverloads constructor(val extent: Extent<*>, var debugNa
             throw BehaviorGraphException("Cannot access the value or event of a resource inside a behavior unless it is supplied or demanded.")
         }
     }
+
+    override fun toString(): String {
+        return String.format("%s (r)", debugName ?: "resource")
+    }
 }

behavior-graph/src/main/kotlin/behaviorgraph/State.kt

@@ -137,6 +137,10 @@ class State<T> @JvmOverloads constructor(extent: Extent<*>, initialState: T, deb
         priorStateDuringEvent = null
     }
 
+    override fun toString(): String {
+        return String.format("%s (s) == %s (%s)", debugName ?: "resource", currentState.value, currentState.event.sequence)
+    }
+
     private data class StateHistory<T>(val value: T, val event: Event)
 }
 

behavior-graph/src/main/kotlin/behaviorgraph/TypedMoment.kt

@@ -28,6 +28,17 @@ class TypedMoment<T> @JvmOverloads constructor(extent: Extent<*>, debugName: Str
             return this._happenedValue!!
         }
 
+    /**
+     * Optional version value() property which may be more convenient.
+     * Returns T if justUpdated is true, null otherwise
+     * Be careful: It is possible that T is also an optional type itself
+     * So this typedMoment could be called with .update(null).
+     * In that case justUpdated will be true but justUpdatedValue would be null.
+     */
+    @get:JvmName("justUpdatedValue")
+    val justUpdatedValue: T?
+        get() = _happenedValue
+
     /**
      * If this Moment has ever been update what was the last Event it was updated.
      * A behavior must demand this resource to access this property.
@@ -66,6 +77,10 @@ class TypedMoment<T> @JvmOverloads constructor(extent: Extent<*>, debugName: Str
         _happened = false
     }
 
+    override fun toString(): String {
+        return String.format("%s (tm) == %s (%s)", debugName ?: "resource", if (_happened) _happenedValue else "NA", event?.sequence)
+    }
+
     /**
      * Is there a current event and was this Moment resource updated during this event.
      * A behavior must demand this resource to access this property.

behavior-graph/src/test/kotlin/behaviorgraph/MomentTest.kt

@@ -80,6 +80,43 @@ class MomentTest : AbstractBehaviorGraphTest() {
         assertTrue(didRun)
     }
 
+    @Test
+    fun `updatedValue returns optional wrapped value`() {
+        // In some cases justUpdatedValue may be easier to work with
+        // than checking for justUpdated and getting the value
+        // however kotlin collapses the nulls, so there's no notion of
+        // unwrapping as you might find in
+        val mr1: TypedMoment<String> = ext.typedMoment()
+        val mr2: TypedMoment<String?> = ext.typedMoment()
+
+        g.action {
+            g.sideEffect {
+                // mr1 was not just updated, so justUpdatedValue is null
+                assertNull(mr1.justUpdatedValue)
+                var run = false
+            }
+        }
+
+        g.action {
+            mr1.update("hello")
+            mr2.update(null)
+
+            g.sideEffect {
+                // mr1 was updated and it's value was hello so justUpdatedValue is hello
+                assertEquals("hello", mr1.justUpdatedValue)
+                // mr2 was also just updated, but with a value of null
+                assertTrue(mr2.justUpdated)
+                // however justUpdatedValue is null, so ?.let pattern will not run
+                var run = false
+                mr2.justUpdatedValue?.let {
+                    run = true
+                    assertNull(it)
+                }
+                assertFalse(run)
+            }
+        }
+    }
+
     //checks below
     @Test
     fun `check happen requires graph`() {

build.gradle

@@ -10,7 +10,7 @@ buildscript {
     }
     dependencies {
         // Build system
-        classpath 'com.android.tools.build:gradle:4.2.2'
+        classpath 'com.android.tools.build:gradle:7.4.2'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
         classpath "org.jetbrains.dokka:dokka-gradle-plugin:$kotlin_version"
     }

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
 #Mon Aug 23 11:41:29 PDT 2021
 distributionBase=GRADLE_USER_HOME
-distributionUrl=https\://services.gradle.org/distributions/gradle-7.2-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.5-bin.zip
 distributionPath=wrapper/dists
 zipStorePath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME