fix(overmind): fix derived

BREAKING CHANGE:
derived has changed typing

Author: christianalfoni

packages/node_modules/overmind/src/derived.test.ts

@@ -11,11 +11,11 @@ describe('Derived', () => {
   test('should instantiate app with derived state', () => {
     type State = {
       foo: string
-      upperFoo: Derive<State, string>
+      upperFoo: string
     }
     const state: State = {
       foo: 'bar',
-      upperFoo: (state) => state.foo.toUpperCase(),
+      upperFoo: derived((state: State) => state.foo.toUpperCase()),
     }
     const config = {
       state,
@@ -41,11 +41,11 @@ describe('Derived', () => {
     }
     type State = {
       foo: string
-      upperFoo: Derive<State, string | null>
+      upperFoo: string
     }
     const state: State = {
       foo: 'bar',
-      upperFoo: (state) => state.foo.toUpperCase()
+      upperFoo: derived((state: State) => state.foo.toUpperCase())
     }
 
     const config = {
@@ -63,8 +63,6 @@ describe('Derived', () => {
       actions: typeof config.actions
     }
     interface Action<Input = void> extends IAction<Config, Input> {}
-    interface Derive<Parent extends IState, Value>
-      extends IDerive<Config, Parent, Value> {}
 
     const app = new Overmind(config)
     const trackStateTree = app.getTrackStateTree()
@@ -91,14 +89,14 @@ describe('Derived', () => {
 
   test('should dynamically add derived', () => {
     const addDerived: Action = ({ state }) => {
-      state.upperFoo = derived<typeof state, string>((state) => state.foo.toUpperCase())
+      state.upperFoo = derived((state: State) => state.foo.toUpperCase())
     }
     const changeFoo: Action = ({ state }) => {
       state.foo = 'bar2'
     }
     type State = {
       foo: string
-      upperFoo: Derive<State, string> | null
+      upperFoo: string
     }
     const state: State = {
       foo: 'bar',
@@ -146,16 +144,16 @@ describe('Derived', () => {
     }
     type State = {
       foo: string
-      upperFoo: Derive<State, () => string>
+      upperFoo: () => string
     }
     const state: State = {
       foo: 'bar',
-      upperFoo: () =>
+      upperFoo: derived(() =>
         function() {
           const state = this[PROXY_TREE].state
 
           return state.foo.toUpperCase()
-        },
+        }),
     }
 
     const config = {
@@ -172,8 +170,7 @@ describe('Derived', () => {
       actions: typeof config.actions
     }
     interface Action<Input = void> extends IAction<Config, Input> {}
-    interface Derive<Parent extends IState, Value>
-      extends IDerive<Config, Parent, Value> {}
+
 
     const app = new Overmind(config)
     const trackStateTree = app.getTrackStateTree()
@@ -196,11 +193,11 @@ describe('Derived', () => {
     }
     type State = {
       foo: string
-      upperFoo: Derive<State, string>
+      upperFoo: string
     }
     const state: State = {
       foo: 'bar',
-      upperFoo: (state) => state.foo.toUpperCase(),
+      upperFoo: derived((state: State) => state.foo.toUpperCase()),
     }
 
     const config = {
@@ -217,8 +214,6 @@ describe('Derived', () => {
       actions: typeof config.actions
     }
     interface Action<Input = void> extends IAction<Config, Input> {}
-    interface Derive<Parent extends IState, Value>
-      extends IDerive<Config, Parent, Value> {}
 
     const app = new Overmind(config)
     const trackStateTree = app.getTrackStateTree()
@@ -239,11 +234,11 @@ describe('Derived', () => {
     expect.assertions(1)
     type State = {
       foo: string
-      upperFoo: Derive<State, string>
+      upperFoo: string
     }
     const state: State = {
       foo: 'bar',
-      upperFoo: (state) => state.foo.toUpperCase(),
+      upperFoo: derived((state: State) => state.foo.toUpperCase()),
     }
     const changeFoo: Action = ({ state }) => {
       state.foo = 'bar2'

packages/node_modules/overmind/src/index.ts

@@ -74,7 +74,7 @@ export { SERIALIZE, rehydrate } from './rehydrate'
 
 export { Statemachine, statemachine } from './statemachine'
 
-export const derived = <S extends IState, V, C = Config>(cb: IDerive<C, S, V>): V => cb as any
+export const derived = <D extends IDerive<any, any, any>>(cb: D): D extends IDerive<any, any, infer O> ? O : never => cb as any
 
 /** This type can be overwriten by app developers if they want to avoid
  * typing and then they can import `Action`,  `Operation` etc. directly from
@@ -84,6 +84,8 @@ export interface Config {}
 
 export interface Context extends IContext<Config> {}
 
+export type RootState = Context["state"]
+
 export interface Action<Value = void, ReturnValue = void>
   extends IAction<Config, Value, ReturnValue> {}
 

packages/node_modules/overmind/src/internalTypes.ts

@@ -5,7 +5,7 @@ import {
   ITrackStateTree,
 } from 'proxy-state-tree'
 
-import { IAction, IConfiguration, IDerive, IOperator, IState } from './types'
+import { IAction,  IOperator, IState } from './types'
 
 export type SubType<Base, Condition> = Pick<
   Base,