feat: add life-cycle events to <State>

Author: streamich

src/State/__tests__/index.test.tsx

@@ -74,6 +74,46 @@ describe('<State>', () => {
       });
 
       expect(foos).toEqual(['bar', 'baz']);
-    })
+    });
+  });
+
+  describe('life-cycle methods', () => {
+    it('fires onMount() with right arguments', () => {
+      const onMount = jest.fn();
+      const onUnmount = jest.fn();
+
+      const wrapper = mount(h(State, {
+        init: {
+          foo: 'bar'
+        },
+        onMount,
+        onUnmount
+      }));
+
+      expect(onMount).toHaveBeenCalledTimes(1);
+      expect(onMount).toHaveBeenCalledWith({
+        foo: 'bar'
+      });
+
+      expect(onUnmount).not.toHaveBeenCalled();
+    });
+
+    it('fires onMount() with right arguments', () => {
+      const onUnmount = jest.fn();
+
+      const wrapper = mount(h(State, {
+        init: {
+          foo: 'bar'
+        },
+        onUnmount
+      }));
+
+      wrapper.unmount();
+
+      expect(onUnmount).toHaveBeenCalledTimes(1);
+      expect(onUnmount).toHaveBeenCalledWith({
+        foo: 'bar'
+      });
+    });
   });
 });

src/State/index.ts

@@ -7,6 +7,8 @@ export interface IStateProps {
   init: object,
   onChange?: (state: any) => void;
   render?: (state: any, setState?) => void;
+  onMount?: (state) => void;
+  onUnmount?: (state) => void;
 }
 
 export interface IStateState {
@@ -15,7 +17,9 @@ export interface IStateState {
 
 export class State extends Component<IStateProps, IStateState> {
   static defaultProps = {
-    onChange: noop
+    onChange: noop,
+    onMount: noop,
+    onUnmount: noop
   };
 
   state: IStateState;
@@ -27,6 +31,14 @@ export class State extends Component<IStateProps, IStateState> {
     this.setState = this.setState.bind(this);
   }
 
+  componentDidMount () {
+    this.props.onMount(this.state);
+  }
+
+  componentWillUnmount () {
+    this.props.onUnmount(this.state);
+  }
+
   render () {
     return renderProp(this.props, this.state, this.setState);
   }