feat(core): added circular reference detection for mutations

core/src/store.ts

@@ -41,19 +41,22 @@ function localiseHandler(name: string, handler: EventHandler): EventHandler {
 export default class Store<TState extends object = any> implements InternalStore<TState> {
 
     private options: InternalStoreOptions;
+    private stack: Set<string>;
     private readState: ReadState<TState>;
     private writeState: WriteState<TState>;
 
     public name: string;
     public getters: Map<string, Function>;
     public mutations: Map<string, Mutation<any>>;
 
+
     constructor(name: string, state: TState, options?: Partial<InternalStoreOptions>) {
         this.options = {
             allowOverwrite: true,
             ...options
         };
 
+        this.stack = new Set();
         this.writeState = reactive(state) as WriteState<TState>;
         this.readState = readonly(this.writeState) as ReadState<TState>;
 
@@ -101,20 +104,27 @@ export default class Store<TState extends object = any> implements InternalStore
     };
 
     private mutate<TPayload, TResult = void>(name: string, sender: string, mutator: Mutator<TState, TPayload, TResult>, payload: TPayload): TResult {
+        if (this.stack.has(name)) {
+            throw new Error('Circular mutation reference detected. Avoid calling mutations inside other mutations to prevent circular references.');
+        }
+
         const eventData: MutationEventData<TPayload, TResult> = {
             payload,
             mutation: name
         };
 
         let result: TResult;
 
+        this.stack.add(name);
         this.emit(EVENTS.mutation.before, sender, eventData);
 
         try {
             result = mutator(this.writeState, payload);
         } catch (error) {
             this.emit(EVENTS.mutation.error, sender, eventData);
             throw error;
+        } finally {
+            this.stack.delete(name);
         }
 
         this.emit(EVENTS.mutation.after, sender, {

core/test/index.test.ts

@@ -35,6 +35,14 @@ function getStore() {
         state.lastName = payload;
     });
 
+    const circularParent = mutation('circular-parent', state => {
+        circularChild();
+    });
+
+    const circularChild = mutation('circular-child', state => {
+        circularParent();
+    });
+
     return {
         state,
         getter,
@@ -43,6 +51,8 @@ function getStore() {
         setId,
         setFirstName,
         setLastName,
+        circularParent,
+        circularChild,
         onBeforeMutation,
         onAfterMutation
     };
@@ -58,6 +68,7 @@ describe('Harlem Core', () => {
         setId,
         setFirstName,
         setLastName,
+        circularParent,
         onBeforeMutation,
         onAfterMutation
     } = getStore();
@@ -119,6 +130,10 @@ describe('Harlem Core', () => {
             expect(typeof id).toBe('number');
         });
 
+        test('Should detect a circular reference', () => {
+            expect(() => circularParent()).toThrow();
+        });
+
     });
 
     describe('Triggers', () => {

jest.config.js

@@ -1,5 +1,5 @@
 module.exports = {
     preset: 'ts-jest',
-    testEnvironment: 'node',
+    testEnvironment: 'jsdom',
     verbose: true
 };