feat(store): split immutibility checks in state and action checks (#1894)

Author: timdeschryver

modules/store/spec/meta-reducers/action_serialization_reducer.spec.ts

@@ -3,55 +3,106 @@ import { immutabilityCheckMetaReducer } from '../../src/meta-reducers';
 describe('immutabilityCheckMetaReducer:', () => {
   describe('actions:', () => {
     it('should not throw if left untouched', () => {
-      expect(() => invokeReducer((action: any) => action)).not.toThrow();
+      expect(() => invokeActionReducer((state: any) => state)).not.toThrow();
     });
 
     it('should throw when mutating an action', () => {
       expect(() =>
-        invokeReducer((action: any) => {
+        invokeActionReducer((state: any, action: any) => {
           action.foo = '123';
+          return state;
         })
       ).toThrow();
       expect(() =>
-        invokeReducer((action: any) => {
+        invokeActionReducer((state: any, action: any) => {
           action.numbers.push(4);
+          return state;
         })
       ).toThrow();
     });
 
-    function invokeReducer(reduce: Function) {
-      immutabilityCheckMetaReducer((state, action) => {
-        reduce(action);
+    it('should throw when mutating action outside of reducer', () => {
+      let dispatchedAction: any;
+      invokeActionReducer((state: any, action: any) => {
+        dispatchedAction = action;
         return state;
+      });
+
+      expect(() => {
+        dispatchedAction.foo = '123';
+      }).toThrow();
+    });
+
+    it('should not throw when check is off', () => {
+      expect(() =>
+        invokeActionReducer((state: any, action: any) => {
+          action.foo = '123';
+          return state;
+        }, false)
+      ).not.toThrow();
+    });
+
+    function invokeActionReducer(reduce: Function, checkIsOn = true) {
+      immutabilityCheckMetaReducer((state, action) => reduce(state, action), {
+        action: checkIsOn,
+        state: false,
       })({}, { type: 'invoke', numbers: [1, 2, 3], fun: function() {} });
     }
   });
 
   describe('state:', () => {
     it('should not throw if left untouched', () => {
       expect(() =>
-        invokeReducer((state: any) => ({ ...state, foo: 'bar' }))
+        invokeStateReducer((state: any) => ({ ...state, foo: 'bar' }))
       ).not.toThrow();
     });
 
     it('should throw when mutating state', () => {
       expect(() =>
-        invokeReducer((state: any) => {
+        invokeStateReducer((state: any) => {
           state.foo = '123';
+          return state;
         })
       ).toThrow();
       expect(() =>
-        invokeReducer((state: any) => {
+        invokeStateReducer((state: any) => {
           state.numbers.push(4);
+          return state;
         })
       ).toThrow();
     });
 
-    function invokeReducer(reduce: Function) {
-      immutabilityCheckMetaReducer(state => reduce(state))(
-        { numbers: [1, 2, 3] },
-        { type: 'invoke' }
+    it('should throw when mutating state outside of reducer', () => {
+      const nextState = invokeStateReducer((state: any) => state);
+      expect(() => {
+        nextState.foo = '123';
+      }).toThrow();
+    });
+
+    it('should not throw when check is off', () => {
+      expect(() =>
+        invokeStateReducer((state: any) => {
+          state.foo = '123';
+          return state;
+        }, false)
+      ).not.toThrow();
+    });
+
+    function invokeStateReducer(reduce: Function, checkIsOn = true) {
+      const reducer = immutabilityCheckMetaReducer(
+        (state, action) => {
+          if (action.type === 'init') return state;
+          return reduce(state, action);
+        },
+        {
+          state: checkIsOn,
+          action: false,
+        }
       );
+
+      // dispatch init noop action because it's the next state that is frozen
+      const state = reducer({ numbers: [1, 2, 3] }, { type: 'init' });
+      return reducer(state, { type: 'invoke' });
     }
   });
 });

modules/store/spec/meta-reducers/immutability_reducer.spec.ts

@@ -0,0 +1,111 @@
+import { serializationCheckMetaReducer } from '../../src/meta-reducers';
+
+describe('serializationCheckMetaReducer:', () => {
+  const serializables: Record<string, any> = {
+    number: { value: 4 },
+    boolean: { value: true },
+    string: { value: 'foobar' },
+    array: { value: [1, 2, 3] },
+    object: { value: {} },
+    nested: { value: { number: 7, array: ['n', 'g', 'r', 'x'] } },
+    null: { value: null },
+    undefined: { value: undefined },
+  };
+
+  const unSerializables: Record<string, any> = {
+    date: { value: new Date() },
+    map: { value: new Map() },
+    set: { value: new Set() },
+    class: { value: new class {}() },
+    function: { value: () => {} },
+  };
+
+  describe('serializable:', () => {
+    Object.keys(serializables).forEach(key => {
+      it(`action with ${key} should not throw`, () => {
+        expect(() =>
+          invokeActionReducer({ type: 'valid', payload: serializables[key] })
+        ).not.toThrow();
+      });
+
+      it(`state with ${key} should not throw`, () => {
+        expect(() => invokeStateReducer(serializables[key])).not.toThrow();
+      });
+    });
+  });
+
+  describe('unserializable:', () => {
+    Object.keys(unSerializables).forEach(key => {
+      it(`action with ${key} should throw`, () => {
+        expect(() =>
+          invokeActionReducer({ type: 'valid', payload: unSerializables[key] })
+        ).toThrow();
+      });
+
+      it(`state with ${key} should throw`, () => {
+        expect(() => invokeStateReducer(unSerializables[key])).toThrow();
+      });
+    });
+  });
+
+  describe('actions: ', () => {
+    it('should not throw if check is off', () => {
+      expect(() =>
+        invokeActionReducer({ type: 'valid', payload: unSerializables }, false)
+      );
+    });
+
+    it('should log the path that is not serializable', () => {
+      expect(() =>
+        invokeActionReducer({
+          type: 'valid',
+          payload: { foo: { bar: unSerializables['date'] } },
+        })
+      ).toThrowError(
+        /Detected unserializable action at "payload.foo.bar.value"/
+      );
+    });
+  });
+
+  describe('state: ', () => {
+    it('should not throw if check is off', () => {
+      expect(() => invokeStateReducer(unSerializables, false)).not.toThrow();
+    });
+
+    it('should log the path that is not serializable', () => {
+      expect(() =>
+        invokeStateReducer({
+          foo: { bar: unSerializables['date'] },
+        })
+      ).toThrowError(/Detected unserializable state at "foo.bar.value"/);
+    });
+
+    it('should not throw if state is null', () => {
+      expect(() => invokeStateReducer(null)).toThrowError(
+        /Detected unserializable state at "root"/
+      );
+    });
+
+    it('should not throw if state is undefined', () => {
+      expect(() => invokeStateReducer(undefined)).toThrowError(
+        /Detected unserializable state at "root"/
+      );
+    });
+  });
+
+  function invokeActionReducer(action: any, checkIsOn = true) {
+    serializationCheckMetaReducer(state => state, {
+      action: checkIsOn,
+      state: false,
+    })(undefined, action);
+  }
+
+  function invokeStateReducer(nextState?: any, checkIsOn = true) {
+    serializationCheckMetaReducer(() => nextState, {
+      state: checkIsOn,
+      action: false,
+    })(undefined, {
+      type: 'invokeReducer',
+    });
+  }
+});