Add isStartTransition method

Author: nsk90

kstatemachine/src/commonMain/kotlin/ru/nsk/kstatemachine/transition/TransitionParams.kt

@@ -8,6 +8,7 @@
 package ru.nsk.kstatemachine.transition
 
 import ru.nsk.kstatemachine.event.Event
+import ru.nsk.kstatemachine.event.StartEvent
 import ru.nsk.kstatemachine.event.WrappedEvent
 import ru.nsk.kstatemachine.statemachine.StateMachineDslMarker
 
@@ -35,4 +36,12 @@ val TransitionParams<*>.unwrappedEvent get() = if (event is WrappedEvent) event.
  * Convenience property for unwrapping original argument.
  * If the event is not [WrappedEvent] this is same as [TransitionParams.argument] property
  */
-val TransitionParams<*>.unwrappedArgument get() = if (event is WrappedEvent) event.argument else argument
+val TransitionParams<*>.unwrappedArgument get() = if (event is WrappedEvent) event.argument else argument
+
+/**
+ * Returns true is the transition is triggered by [StartEvent].
+ * This means that the StateMachine is starting.
+ * Might be useful to check if you're entering some State just by a machine startup
+ * or by outside event.
+ */
+val TransitionParams<*>.isStartTransition get() = event is StartEvent

tests/src/commonTest/kotlin/ru/nsk/kstatemachine/statemachine/StateMachineTest.kt

@@ -12,6 +12,7 @@ import io.kotest.assertions.throwables.shouldThrowUnitWithMessage
 import io.kotest.assertions.throwables.shouldThrowWithMessage
 import io.kotest.core.spec.style.FreeSpec
 import io.kotest.datatest.withData
+import io.kotest.matchers.collections.shouldContain
 import io.kotest.matchers.collections.shouldContainExactlyInAnyOrder
 import io.kotest.matchers.shouldBe
 import io.kotest.matchers.string.shouldEndWith
@@ -26,10 +27,7 @@ import ru.nsk.kstatemachine.state.*
 import ru.nsk.kstatemachine.statemachine.StateMachineTestData.OffEvent
 import ru.nsk.kstatemachine.statemachine.StateMachineTestData.OnEvent
 import ru.nsk.kstatemachine.testing.Testing.startFromBlocking
-import ru.nsk.kstatemachine.transition.DefaultTransition
-import ru.nsk.kstatemachine.transition.Transition
-import ru.nsk.kstatemachine.transition.TransitionType
-import ru.nsk.kstatemachine.transition.onTriggered
+import ru.nsk.kstatemachine.transition.*
 
 private object StateMachineTestData {
     object OnEvent : Event
@@ -363,6 +361,22 @@ class StateMachineTest : FreeSpec({
                 }
             }
 
+            "isStartTransition" {
+                lateinit var state2: State
+                val machine = createTestStateMachine(coroutineStarterType) {
+                    state2 = state("state2") {
+                        onEntry { it.isStartTransition shouldBe false }
+                    }
+                    initialState("initial") {
+                        onEntry { it.isStartTransition shouldBe true }
+                        transitionOn<SwitchEvent> { targetState = { state2 } }
+                    }
+                    onStarted { it.isStartTransition shouldBe true }
+                }
+                machine.processEvent(SwitchEvent)
+                machine.activeStates().shouldContain(state2)
+            }
+
             "destroy from onStart" {
                 val callbacks = mockkCallbacks()
                 val machine = createTestStateMachine(coroutineStarterType) {