State.initial now represents initial transition

packages/core/src/StateNode.ts

@@ -227,21 +227,10 @@ export class StateNode<
         : undefined;
   }
 
-  /**
-   * The initial state node key.
-   */
-  public get initial(): keyof TStateSchema['states'] | undefined {
-    const init = this._initial;
-
-    return init
-      ? (init.target[0].key as keyof TStateSchema['states'])
-      : undefined;
-  }
-
   /**
    * The initial state node transition.
    */
-  public get _initial():
+  public get initial():
     | InitialTransitionDefinition<TContext, TEvent>
     | undefined {
     return this.config.initial
@@ -436,16 +425,12 @@ export class StateNode<
         stateNode => !(stateNode.type === 'history')
       );
     } else if (this.initial !== undefined) {
-      if (!this.states[this.initial]) {
-        throw new Error(
-          `Initial state '${this.initial}' not found on '${this.key}'`
-        );
-      }
+      const [initialTargetNode] = this.initial.target;
 
-      initialStateValue = (isLeafNode(this.states[this.initial])
-        ? this.initial
+      initialStateValue = (isLeafNode(initialTargetNode)
+        ? initialTargetNode.key
         : {
-            [this.initial]: this.states[this.initial].initialStateValue
+            [initialTargetNode.key]: initialTargetNode.initialStateValue
           }) as StateValue;
     }
 

packages/core/src/stateUtils.ts

@@ -742,12 +742,10 @@ export function getStateNodes<TContext, TEvent extends EventObject>(
       : toStateValue(state, stateNode.machine.delimiter);
 
   if (isString(stateValue)) {
-    const initialStateValue = getStateNode(stateNode, stateValue).initial;
+    const { initial } = getStateNode(stateNode, stateValue);
 
-    return initialStateValue !== undefined
-      ? getStateNodes(stateNode, {
-          [stateValue]: initialStateValue
-        } as StateValue)
+    return initial !== undefined
+      ? initial.target!
       : [stateNode.states[stateValue]];
   }
 
@@ -1330,7 +1328,7 @@ function addDescendentStatesToEnter<TContext, TEvent extends EventObject>(
     mutStatesToEnter.add(stateNode);
     if (stateNode.type === 'compound') {
       mutStatesForDefaultEntry.add(stateNode);
-      const initialStateNode = stateNode.states[stateNode.initial as string];
+      const initialStateNode = stateNode.initial!.target[0];
       addDescendentStatesToEnter(
         initialStateNode,
         state,

packages/core/src/types.ts

@@ -371,10 +371,9 @@ export interface StateNodeConfig<
    */
   key?: string;
   /**
-   * The initial state node key.
+   * The initial state transition.
    */
-  initial?: keyof TStateSchema['states'] | undefined;
-  _initial?: InitialTransitionConfig<TContext, TEvent> | string | undefined;
+  initial?: InitialTransitionConfig<TContext, TEvent> | string | undefined;
   /**
    * The type of this state node:
    *
@@ -470,7 +469,7 @@ export interface StateNodeDefinition<
   version?: string | undefined;
   key: string;
   type: 'atomic' | 'compound' | 'parallel' | 'final' | 'history';
-  initial: StateNodeConfig<TContext, TStateSchema, TEvent>['initial'];
+  initial: InitialTransitionDefinition<TContext, TEvent> | undefined;
   history: boolean | 'shallow' | 'deep' | undefined;
   states: StatesDefinition<TContext, TStateSchema, TEvent>;
   on: TransitionDefinitionMap<TContext, TEvent>;

packages/core/test/interpreter.test.ts

@@ -615,11 +615,9 @@ describe('interpreter', () => {
       deferEvents: false
     });
 
-    expect(() => service.send('SOME_EVENT'))
-      .toThrowErrorMatchingInlineSnapshot(`
-      "Event \\"SOME_EVENT\\" was sent to uninitialized service \\"light\\". Make sure .start() is called for this service, or set { deferEvents: true } in the service options.
-      Event: {\\"type\\":\\"SOME_EVENT\\"}"
-    `);
+    expect(() => service.send('SOME_EVENT')).toThrowError(
+      /Event \"SOME_EVENT\" was sent to uninitialized service \"light\"/
+    );
 
     service.start();
 

packages/xstate-scxml/src/index.ts

@@ -149,7 +149,7 @@ function stateNodeToSCXML(stateNode: StateNode<any, any, any>): XMLElement {
         : 'state',
     attributes: {
       id: stateNode.id,
-      initial: stateNode.initial as string
+      initial: stateNode.initial ? `${stateNode.initial.target[0]}` : undefined
     },
     elements
   };