TypeScript updates for 0.6 (#1561)

Summary:
Pull Request resolved: #1561

* Add `isRetained()` to `Snapshot` methods
* Remove `undefined` from `type` in `RecoilStateInfo`

Drive-by cleanup of wording in warning when using released snapshots to change pseudo-function name to avoid starting with `use` so it doesn't look like a hook.

Reviewed By: habond

Differential Revision: D33593402

fbshipit-source-id: ab35f4e85fd9a15ae2ff090b8d22d36ae43a796a

CHANGELOG.md

@@ -34,7 +34,6 @@
 - Fix transitive selector refresh for some cases (#1409)
 - Fix some corner cases with async selectors and multiple stores (#1568)
 - Atom Effects
-  - Rename option from `effects_UNSTABLE` to just `effects` as the interface is mostly stabilizing (#1520)
   - Run atom effects when atoms are initialized from a set during a transaction from `useRecoilTransaction_UNSTABLE()` (#1466)
   - Atom effects are cleaned up when initialized by a Snapshot which is released. (#1511, #1532)
   - Unsubscribe `onSet()` handlers in atom effects when atoms are cleaned up. (#1509)
@@ -46,6 +45,7 @@
 - Memoize the results of lazy proxies. (#1548)
 
 ### Breaking Changes
+- Rename atom effects from `effects_UNSTABLE` to just `effects`, as the interface is mostly stabilizing. (#1520)
 - Atom effect initialization takes precedence over initialization with `<RecoilRoot initializeState={...} >`. (#1509)
 - `useGetRecoilValueInfo_UNSTABLE()` and `Snapshot#getInfo_UNSTABLE()` always report the node `type`. (#1547)
 

packages/recoil/core/Recoil_Snapshot.js

@@ -61,7 +61,7 @@ Recoil Snapshots only last for the duration of the callback they are provided to
 
   const release = snapshot.retain();
   try {
-    await useTheSnapshotAsynchronously(snapshot);
+    await doSomethingWithSnapshot(snapshot);
   } finally {
     release();
   }

typescript/index.d.ts

@@ -69,6 +69,7 @@
   map(cb: (mutableSnapshot: MutableSnapshot) => void): Snapshot;
   asyncMap(cb: (mutableSnapshot: MutableSnapshot) => Promise<void>): Promise<Snapshot>;
   retain(): () => void;
+  isRetained(): boolean;
  }
 
  export class MutableSnapshot extends Snapshot {

typescript/tests.ts

@@ -260,6 +260,7 @@ useRecoilCallback(({ snapshot, set, reset, refresh, gotoSnapshot, transact_UNSTA
 
   const release = snapshot.retain(); // $ExpectType () => void
   release(); // $ExpectType void
+  snapshot.isRetained(); // $ExpectType boolean
 
   transact_UNSTABLE(({get, set, reset}) => {
     const x: number = get(myAtom); // eslint-disable-line @typescript-eslint/no-unused-vars