implement and test value.reset, value.clear

src/Value/docs.md

@@ -23,6 +23,14 @@ A standard redux reducer to be passed to `redux.combineReducers`.
 
 sets the state to `nextValue`.
 
+### `reset()`
+
+sets the state to its initial state.
+
+### `clear()`
+
+sets the state to `null`.
+
 ## Example
 
 `name.js`

src/Value/index.js

@@ -9,14 +9,30 @@ export default function Value(name, initialState=null){
                 type: createActionType('set'),
                 value: nextValue
             })
+        },
+        clear(){
+            return ({
+                type: createActionType('clear')
+            })
+        },
+        reset(){
+            return ({
+                type: createActionType('reset')
+            })
         }
     }
     const reducer = (state=initialState, action) => {
         if(!matchInstance(action)) return state
+        if(action.type.endsWith('reset')){
+            return initialState
+        }
         if(action.type.endsWith('set')){
             return action.value
         }
-        else return state
+        if(action.type.endsWith('clear')){
+            return null
+        }
+        return state
     }
 
     return {

src/Value/test/value.test.js

@@ -28,6 +28,17 @@ test('Value', main => {
         t.equal( reducer(initialState, actions.set(nextState)), nextState)
         t.end()
     })
+    main.test('`reset` action', t => {
+        const initialState = 9
+        const { actions, reducer } = Value('test-name-3', initialState)
+        t.equal( reducer(initialState, actions.reset()), initialState)
+        t.end()
+    })
+    main.test('`clear` action', t => {
+        const { actions, reducer } = Value('test-name-4')
+        t.equal( reducer([1, 2, 3], actions.clear()), null)
+        t.end()
+    })
     main.test('multiple instances', t => {
         const n0 = 'name-0'
         const n1 = 'name-1'
@@ -50,8 +61,8 @@ test('Value', main => {
     })
     main.test('invariants', t => {
         t.test('duplicate name', t => {
-            const v0 = Value('test-name-3')
-            t.throws(() => Value('test-name-3'), 'should throw when creating an instance with an already existing name')
+            const v0 = Value('name-3')
+            t.throws(() => Value('name-3'), 'should throw when creating an instance with an already existing name')
             t.end()
         })
         t.test('undefined name', t => {