refactor(core): remove duplicated code (#654)

.size-snapshot.json

@@ -1,8 +1,8 @@
 {
  "index.js": {
- "bundled": 22369,
- "minified": 8941,
- "gzipped": 3292,
+ "bundled": 22130,
+ "minified": 8884,
+ "gzipped": 3283,
  "treeshaked": {
  "rollup": {
  "code": 14,
@@ -28,9 +28,9 @@
  }
  },
  "devtools.js": {
- "bundled": 20665,
- "minified": 8437,
- "gzipped": 3180,
+ "bundled": 20426,
+ "minified": 8380,
+ "gzipped": 3171,
  "treeshaked": {
  "rollup": {
  "code": 28,

src/core/store.ts

@@ -258,18 +258,7 @@ export const createStore = (
  try {
  const promiseOrValue = atom.read((a: AnyAtom) => {
  dependencies.add(a)
- if (a !== atom) {
- const aState = readAtomState(a)
- if (aState.e) {
- throw aState.e // read error
- }
- if (aState.p) {
- throw aState.p // read promise
- }
- return aState.v // value
- }
- // a === atom
- const aState = getAtomState(a)
+ const aState = a === atom ? getAtomState(a) : readAtomState(a)
  if (aState) {
  if (aState.e) {
  throw aState.e // read error
@@ -282,6 +271,7 @@ export const createStore = (
  if (hasInitialValue(a)) {
  return a.init
  }
+ // NOTE invalid derived atoms can reach here
  throw new Error('no atom init')
  })
  if (promiseOrValue instanceof Promise) {
@@ -638,15 +628,14 @@ export const createStore = (
  [DEV_GET_ATOM_STATE]: (a: AnyAtom) => atomStateMap.get(a),
  [DEV_GET_MOUNTED]: (a: AnyAtom) => mountedMap.get(a),
  }
- } else {
- return {
- [GET_VERSION]: () => version,
- [READ_ATOM]: readAtom,
- [WRITE_ATOM]: writeAtom,
- [FLUSH_PENDING]: flushPending,
- [SUBSCRIBE_ATOM]: subscribeAtom,
- [RESTORE_ATOMS]: restoreAtoms,
- }
+ }
+ return {
+ [GET_VERSION]: () => version,
+ [READ_ATOM]: readAtom,
+ [WRITE_ATOM]: writeAtom,
+ [FLUSH_PENDING]: flushPending,
+ [SUBSCRIBE_ATOM]: subscribeAtom,
+ [RESTORE_ATOMS]: restoreAtoms,
  }
 }