Fix synchronous suspense cases on client-side (#506)

* Add simplified toSuspenseSource implementation

* Upgrade to wonka@^4.0.7 and react-wonka@^2.0.1

* Add test to confirm that toSuspenseSource ends on suspense

package.json

@@ -136,8 +136,8 @@
  "react": ">= 16.8.0"
  },
  "dependencies": {
- "react-wonka": "^2.0.0",
+ "react-wonka": "^2.0.1",
  "scheduler": ">= 0.16.0",
- "wonka": "^4.0.5"
+ "wonka": "^4.0.7"
  }
 }

src/utils/toSuspenseSource.test.ts

@@ -72,7 +72,9 @@ it('throws a promise that resolves when the source emits a value', () => {
  expect(promise).toBeInstanceOf(Promise);
 
  next('test');
- expect(result).toBe('test');
+
+ // The result came in asynchronously and the original source has ended
+ expect(result).toBe(undefined);
 
  return promise.then(resolved => {
  expect(resolved).toBe('test');

src/utils/toSuspenseSource.ts

@@ -1,48 +1,20 @@
-import { pipe, make, onPush, onEnd, subscribe, Source } from 'wonka';
+import { pipe, share, onPush, toPromise, takeWhile, take, Source } from 'wonka';
 
 /** This converts a Source to a suspense Source; It will forward the first result synchronously or throw a promise that resolves when the result becomes available */
-export const toSuspenseSource = <T>(source: Source<T>): Source<T> => {
- // Create a new Source from scratch so we have full control over the Source's lifecycle
- return make<T>(({ next, complete }) => {
- let isCancelled = false;
- let resolveSuspense: (value: T) => void;
- let synchronousResult: undefined | T;
+export const toSuspenseSource = <T>(source: Source<T>): Source<T> => sink => {
+ const shared = share(source);
+ let hasResult = false;
+ let hasSuspended = false;
 
- const { unsubscribe } = pipe(
- source,
- // The onPush and onEnd forward the underlying results as usual, so that when no
- // suspense promise is thrown, the source behaves as it normally would
- onPush(next),
- onEnd(complete as any),
- subscribe(value => {
- // When this operation resolved synchronously assign the result to
- // synchronousResult which will be picked up below
- if (resolveSuspense === undefined) {
- synchronousResult = value;
- } else if (!isCancelled) {
- // Otherwise resolve the thrown promise,
- resolveSuspense(value);
- // And end and teardown both sources, since suspense will abort the
- // underlying rendering component anyway
- complete();
- unsubscribe();
- }
- })
- );
+ pipe(
+ shared,
+ takeWhile(() => !hasSuspended),
+ onPush(() => (hasResult = true))
+ )(sink);
 
- // If we have a synchronous result, push it onto this source, which is synchronous
- // otherwise throw a new promise which will resolve later
- if (synchronousResult === undefined) {
- throw new Promise(resolve => {
- resolveSuspense = resolve;
- });
- }
-
- // Since promises aren't cancellable we have a flag that prevents
- // the thrown promise from resolving if this source is cancelled
- return () => {
- isCancelled = true;
- unsubscribe();
- };
- });
+ if (!hasResult) {
+ hasSuspended = true;
+ sink(0); /* End */
+ throw pipe(shared, take(1), toPromise);
+ }
 };

yarn.lock

@@ -4718,10 +4718,10 @@ react-test-renderer@^16.0.0-0, react-test-renderer@^16.12.0:
  react-is "^16.8.6"
  scheduler "^0.18.0"
 
-react-wonka@^2.0.0:
- version "2.0.0"
- resolved "https://registry.yarnpkg.com/react-wonka/-/react-wonka-2.0.0.tgz#d62d87c9c93ec3e603ecf1582df3615aadc5c2e9"
- integrity sha512-7q0CNBnSltRyzb61joCxKqVntHbRJRhP/WPxEx+zM8l9Yd+0IRevJuPG8iCamgrGphusX5xtEtd4yyX7qvRM1g==
+react-wonka@^2.0.1:
+ version "2.0.1"
+ resolved "https://registry.yarnpkg.com/react-wonka/-/react-wonka-2.0.1.tgz#75bdf03dbad8ceb8c1066216f635f05ce2b642a5"
+ integrity sha512-mM2UH2gnK5LLzaqVWd6JCLrB1vO3I4PN/sQZbjvzsjms4vSv+nKwelNUftM0KeC+LtTPC4GGsuxyu2XJnsCUTw==
 
 react@^16.12.0:
  version "16.12.0"
@@ -5981,10 +5981,10 @@ wide-align@^1.1.0:
  dependencies:
  string-width "^1.0.2 || 2"
 
-wonka@^4.0.5:
- version "4.0.5"
- resolved "https://registry.yarnpkg.com/wonka/-/wonka-4.0.5.tgz#3384b90ed8c1e6e182d6e2fb18468c33ab94e0af"
- integrity sha512-XKnzSpsk2UcPfyjecdc14b7LZSPeOEhYEs+/oAZ+gXV9BuYIcZC3hpapFi2DFHj1Bk38/npusgkiSD0+KdyCzQ==
+wonka@^4.0.7:
+ version "4.0.7"
+ resolved "https://registry.yarnpkg.com/wonka/-/wonka-4.0.7.tgz#b4934685bd2449367bd72ce7770bfe3e6cc8a68b"
+ integrity sha512-Uhyl2cgWCUksYtU0Jt8MSzKUqK4BVUrewWxnn1YlKL3Zco4sDcCUDkbgH0i762HJs1rtsq03cfzsCWxJKaDgVg==
 
 word-wrap@~1.2.3:
  version "1.2.3"