feat(proxy-state-tree): expose symbol to access tree of proxy

Author: christianalfoni

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

@@ -1,4 +1,6 @@
-import { Overmind, IAction, IDerive, IState } from './'
+import { PROXY_TREE } from 'proxy-state-tree'
+
+import { IAction, IDerive, IState, Overmind } from './'
 
 type State = {
   foo: string
@@ -29,7 +31,57 @@ describe('Derived', () => {
     expect(app.state.upperFoo).toEqual('BAR')
   })
 
-  test.only('should track derived state', () => {
+  test('should allow access to proxy state tree to continue tracking with derived function', () => {
+    let renderCount = 0
+    const changeFoo: Action = ({ state }) => {
+      state.foo = 'bar2'
+    }
+    type State = {
+      foo: string
+      upperFoo: Derive<State, () => string>
+    }
+    const state: State = {
+      foo: 'bar',
+      upperFoo: () =>
+        function() {
+          const state = this[PROXY_TREE].state
+
+          return state.foo.toUpperCase()
+        },
+    }
+
+    const config = {
+      state,
+      actions: {
+        changeFoo,
+      },
+    }
+    type Config = {
+      state: {
+        foo: string
+        upperFoo: string
+      }
+      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()
+    const onTrack = () => {
+      renderCount++
+    }
+    function render() {
+      trackStateTree.track(onTrack)
+      app.state.upperFoo()
+    }
+    render()
+    app.actions.changeFoo()
+    expect(renderCount).toBe(1)
+  })
+
+  test('should track derived state', () => {
     let renderCount = 0
     const changeFoo: Action = ({ state }) => {
       state.foo = 'bar2'
@@ -173,7 +225,6 @@ describe('Derived', () => {
         expect(trackStateTree.state.nestedDerived).toBe('BAR2!!!')
       }
       trackStateTree.stopTracking()
-      console.log(trackStateTree.pathDependencies)
     }
 
     trackStateTree.track(render)

packages/node_modules/proxy-state-tree/src/Proxyfier.ts

@@ -1,9 +1,11 @@
-import { TTree, ITrackStateTree, IMutationTree } from './types'
 import isPlainObject from 'is-plain-obj'
 
+import { IMutationTree, ITrackStateTree, TTree } from './types'
+
 export const IS_PROXY = Symbol('IS_PROXY')
 export const PATH = Symbol('PATH')
 export const VALUE = Symbol('VALUE')
+export const PROXY_TREE = Symbol('PROXY_TREE')
 
 const arrayMutations = new Set([
   'push',
@@ -206,6 +208,7 @@ export class Proxifier {
         if (prop === IS_PROXY) return true
         if (prop === PATH) return path
         if (prop === VALUE) return object
+        if (prop === PROXY_TREE) return proxifier.tree
 
         if (typeof prop === 'symbol' || prop in Object.prototype)
           return target[prop]

packages/node_modules/proxy-state-tree/src/index.ts

@@ -1,22 +1,24 @@
-import { IS_PROXY, VALUE, PATH, Proxifier } from './Proxyfier'
 import isPlainObject from 'is-plain-obj'
+
+import { MutationTree } from './MutationTree'
+import { IS_PROXY, PATH, PROXY_TREE, Proxifier, VALUE } from './Proxyfier'
+import { TrackStateTree } from './TrackStateTree'
 import {
+  IFlushCallback,
   IMutation,
-  IMutationTree,
   IMutationCallback,
+  IMutationTree,
+  IOptions,
+  IProxifier,
+  IProxyStateTree,
   ITrackCallback,
   ITrackStateTree,
   TTree,
-  IOptions,
-  IProxyStateTree,
-  IFlushCallback,
-  IProxifier,
 } from './types'
-import { MutationTree } from './MutationTree'
-import { TrackStateTree } from './TrackStateTree'
 
 export {
   IS_PROXY,
+  PROXY_TREE,
   VALUE,
   PATH,
   IMutation,