fix(proxy-state-tree): support second argument to indexOf

Author: FWeinb

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

@@ -16,6 +16,9 @@ const arrayMutations = new Set([
   'copyWithin',
 ])
 
+const getValue = (proxyOrValue) =>
+  proxyOrValue && proxyOrValue[IS_PROXY] ? proxyOrValue[VALUE] : proxyOrValue
+
 export class Proxifier {
   CACHED_PROXY = Symbol('CACHED_PROXY')
   constructor(private tree: TTree) {}
@@ -105,7 +108,8 @@ export class Proxifier {
         if (prop === PATH) return path
         if (prop === VALUE) return value
         if (prop === 'indexOf') {
-          return (arg) => value.indexOf(arg && arg[IS_PROXY] ? arg[VALUE] : arg)
+          return (searchTerm, offset) =>
+            value.indexOf(getValue(searchTerm), getValue(offset))
         }
         if (
           prop === 'length' ||

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

@@ -369,6 +369,17 @@ describe('ARRAYS', () => {
     })
   })
 
+  test('should create proxies of arrays', () => {
+    const state = {
+      foo: [],
+    }
+    const tree = new ProxyStateTree(state)
+    const trackStateTree = tree.getTrackStateTree().track(() => {})
+    const foo = trackStateTree.state.foo
+
+    expect(foo[IS_PROXY]).toBeTruthy()
+  })
+
   describe('MUTATIONS', () => {
     test('should throw when mutating without tracking mutations', () => {
       const state = {
@@ -493,24 +504,15 @@ describe('ARRAYS', () => {
     })
   })
 
-  test('should allow CONCAT of existing array', () => {
+  test('should allow indexOf using proxy values', () => {
     const state = {
-      foo: ['foo'],
+      things: [{ some: 'thing' }],
+      ids: [2, 1, 1, 1, 2],
     }
     const tree = new ProxyStateTree(state)
-    const mutationTree = tree.getMutationTree()
-    mutationTree.state.foo = mutationTree.state.foo.concat('bar')
-
-    expect(mutationTree.mutations).toEqual([
-      {
-        method: 'set',
-        path: 'foo',
-        args: [['foo', 'bar']],
-        hasChangedValue: true,
-      },
-    ])
-
-    expect(state.foo).toEqual(['foo', 'bar'])
+    expect(tree.state.things.indexOf(tree.state.things[0])).toEqual(0)
+    expect(tree.state.ids.indexOf(2)).toEqual(0)
+    expect(tree.state.ids.indexOf(2, 1)).toEqual(4)
   })
 })