Merge branch 'development' into sse-and-backoff

package-lock.json

@@ -1105,9 +1105,9 @@
             "license": "MIT"
         },
         "node_modules/@eslint/config-array/node_modules/brace-expansion": {
-            "version": "1.1.15",
+            "version": "1.1.16",
-            "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.15.tgz",
+            "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.16.tgz",
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             "dev": true,
             "license": "MIT",
             "dependencies": {
@@ -1186,9 +1186,9 @@
             "license": "MIT"
         },
         "node_modules/@eslint/eslintrc/node_modules/brace-expansion": {
-            "version": "1.1.15",
+            "version": "1.1.16",
-            "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.15.tgz",
+            "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.16.tgz",
-            "integrity": "sha512-EwOCDEex4quD37XhqM3omwtMoJjr//isUZz1JopUNWms+4Z2ViyM/k1YIRePpoVNnQhENnxtFjLaxNHrT7xIUg==",
+            "integrity": "sha512-IDw48K2/2kRkg9LdJxurvq3lV3aBgq0REY89duEqFRthjlPdXHKMj7EnQOXVckxzgisinf3nHfrcE2FufFLXMw==",
             "dev": true,
             "license": "MIT",
             "dependencies": {
@@ -3435,9 +3435,9 @@
             }
         },
         "node_modules/body-parser": {
-            "version": "1.20.5",
+            "version": "1.20.6",
-            "resolved": "https://registry.npmjs.org/body-parser/-/body-parser-1.20.5.tgz",
+            "resolved": "https://registry.npmjs.org/body-parser/-/body-parser-1.20.6.tgz",
-            "integrity": "sha512-3grm+/2tUOvu2cjJkvsIxrv/wVpfXQW4PsQHYm7yk4vfpu7Ekl6nEsYBoJUL6qDwZUx8wUhQ8tR2qz+ad9c9OA==",
+            "integrity": "sha512-p5tAzS57i5MV9fZFDj9LeIiTZEufbSe2eDozP+ElheSUq1m74CRq1jI4mYNDdVs9vQztXFLuk/Gd6BWTdwRJ5g==",
             "dev": true,
             "license": "MIT",
             "dependencies": {
@@ -3503,9 +3503,9 @@
             }
         },
         "node_modules/brace-expansion": {
-            "version": "5.0.6",
+            "version": "5.0.7",
-            "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-5.0.6.tgz",
+            "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-5.0.7.tgz",
-            "integrity": "sha512-kLpxurY4Z4r9sgMsyG0Z9uzsBlgiU/EFKhj/h91/8yHu0edo7XuixOIH3VcJ8kkxs6/jPzoI6U9Vj3WqbMQ94g==",
+            "integrity": "sha512-7oFy703dxfY3/NLxC1fh2SUCQ0H9rmAY+5EpDVfXjUTTs+HEwR2nYaqLv+GWcTsumwxPfiz6CzCNkwXwBUwqCA==",
             "dev": true,
             "license": "MIT",
             "dependencies": {
@@ -5292,9 +5292,9 @@
             "peer": true
         },
         "node_modules/eslint-plugin-import/node_modules/brace-expansion": {
-            "version": "1.1.15",
+            "version": "1.1.16",
-            "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.15.tgz",
+            "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.16.tgz",
-            "integrity": "sha512-EwOCDEex4quD37XhqM3omwtMoJjr//isUZz1JopUNWms+4Z2ViyM/k1YIRePpoVNnQhENnxtFjLaxNHrT7xIUg==",
+            "integrity": "sha512-IDw48K2/2kRkg9LdJxurvq3lV3aBgq0REY89duEqFRthjlPdXHKMj7EnQOXVckxzgisinf3nHfrcE2FufFLXMw==",
             "dev": true,
             "license": "MIT",
             "peer": true,
@@ -5379,9 +5379,9 @@
             "peer": true
         },
         "node_modules/eslint-plugin-jsx-a11y/node_modules/brace-expansion": {
-            "version": "1.1.15",
+            "version": "1.1.16",
-            "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.15.tgz",
+            "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.16.tgz",
-            "integrity": "sha512-EwOCDEex4quD37XhqM3omwtMoJjr//isUZz1JopUNWms+4Z2ViyM/k1YIRePpoVNnQhENnxtFjLaxNHrT7xIUg==",
+            "integrity": "sha512-IDw48K2/2kRkg9LdJxurvq3lV3aBgq0REY89duEqFRthjlPdXHKMj7EnQOXVckxzgisinf3nHfrcE2FufFLXMw==",
             "dev": true,
             "license": "MIT",
             "peer": true,
@@ -5468,9 +5468,9 @@
             "peer": true
         },
         "node_modules/eslint-plugin-react/node_modules/brace-expansion": {
-            "version": "1.1.15",
+            "version": "1.1.16",
-            "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.15.tgz",
+            "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.16.tgz",
-            "integrity": "sha512-EwOCDEex4quD37XhqM3omwtMoJjr//isUZz1JopUNWms+4Z2ViyM/k1YIRePpoVNnQhENnxtFjLaxNHrT7xIUg==",
+            "integrity": "sha512-IDw48K2/2kRkg9LdJxurvq3lV3aBgq0REY89duEqFRthjlPdXHKMj7EnQOXVckxzgisinf3nHfrcE2FufFLXMw==",
             "dev": true,
             "license": "MIT",
             "peer": true,
@@ -5542,9 +5542,9 @@
             "license": "MIT"
         },
         "node_modules/eslint/node_modules/brace-expansion": {
-            "version": "1.1.15",
+            "version": "1.1.16",
-            "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.15.tgz",
+            "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.16.tgz",
-            "integrity": "sha512-EwOCDEex4quD37XhqM3omwtMoJjr//isUZz1JopUNWms+4Z2ViyM/k1YIRePpoVNnQhENnxtFjLaxNHrT7xIUg==",
+            "integrity": "sha512-IDw48K2/2kRkg9LdJxurvq3lV3aBgq0REY89duEqFRthjlPdXHKMj7EnQOXVckxzgisinf3nHfrcE2FufFLXMw==",
             "dev": true,
             "license": "MIT",
             "dependencies": {
@@ -7129,9 +7129,9 @@
             "license": "MIT"
         },
         "node_modules/js-yaml": {
-            "version": "4.2.0",
+            "version": "4.3.0",
-            "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-4.2.0.tgz",
+            "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-4.3.0.tgz",
-            "integrity": "sha512-ePWsvanv0DWuDRsW8dnt+R4jQ31SCRCQ7hhNcPXZPsoBZiemuZNYGf7adZdqX2D86j6rvKp3RpCxVTSb8WQlOw==",
+            "integrity": "sha512-1td788aAnnZ5qs7V2QIRl1owjtYpbKt749Y3xauqQgwIIGF/xXWz1wMTEBx5O3LK3lXLVuqXPdPxj2BoFHaW9Q==",
             "dev": true,
             "funding": [
                 {
@@ -7524,9 +7524,9 @@
             }
         },
         "node_modules/linkify-it": {
-            "version": "5.0.1",
+            "version": "5.0.2",
-            "resolved": "https://registry.npmjs.org/linkify-it/-/linkify-it-5.0.1.tgz",
+            "resolved": "https://registry.npmjs.org/linkify-it/-/linkify-it-5.0.2.tgz",
-            "integrity": "sha512-wVoTjP4Q6R0NW5hiZkVJaFZPWgtXfoGF+6LucL3/FtiNjmcHhYjEr5f1Kqjirc1nBW07J/ZuRFumqr2oqccEWg==",
+            "integrity": "sha512-ONTm2jCMAVZjgQa/Fy1kScXsuOoF5NPTsoFBdE1KVIZ2vAh/r9+Bqo+0jINCBYnavTPQZz38QzFTme79ENoN3Q==",
             "dev": true,
             "funding": [
                 {

source/sse-session/async-push-iterator.ts

@@ -23,24 +23,31 @@
  */
 export class AsyncPushIterator<T> {
     /** ReadableStream backing the async iterator returned from {@link Symbol.asyncIterator}. */
-    private readonly stream: ReadableStream<T>;
+    #stream: ReadableStream<T>;
 
     /** Controller used to enqueue values and close the stream from {@link push} and {@link close}. */
-    private controller: ReadableStreamDefaultController<T> | undefined;
+    #controller: ReadableStreamDefaultController<T> | undefined;
 
     /** When true, no more values are accepted and iteration eventually completes. */
-    public closed = false;
+    #closed = false;
 
     public constructor() {
         // `start`'s `this` is the underlying source object when using a plain method.
         // An arrow function captures the class instance so the controller is stored here.
-        this.stream = new ReadableStream({
+        this.#stream = new ReadableStream({
             start: (controller: ReadableStreamDefaultController<T>): void => {
-                this.controller = controller;
+                this.#controller = controller;
             },
         });
     }
 
+    /**
+     * Flag indicating if the iterator is closed.
+     */
+    public get closed(): boolean {
+        return this.#closed;
+    }
+
     /**
      * Enqueues a value for the consumer.
      *
@@ -49,9 +56,22 @@ export class AsyncPushIterator<T> {
      * @param value - The next value to yield from the iterator.
      */
     push(value: T): void {
-        if (this.closed) return;
+        if (this.#closed) return;
 
-        this.controller?.enqueue(value);
+        this.#controller?.enqueue(value);
+    }
+
+    /**
+     * Causes any future interactions with the associated stream to error with {@link error}.
+     * Calling this will also clear the pending values immediately, so iterators that were listening will not receive them.
+     *
+     * @param error - The error to throw from the stream.
+     */
+    error(error: Error): void {
+        if (this.#closed) return;
+
+        this.#closed = true;
+        this.#controller?.error(error);
     }
 
     /**
@@ -61,10 +81,10 @@ export class AsyncPushIterator<T> {
      * Buffered values are still yielded before iteration completes.
      */
     close(): void {
-        this.closed = true;
+        this.#closed = true;
 
         try {
-            this.controller?.close();
+            this.#controller?.close();
         } catch {
             // The reader may already have released or cancelled the stream.
         }
@@ -75,8 +95,11 @@ export class AsyncPushIterator<T> {
      *
      * Uses `preventCancel: true` so early `break` from `for await...of` does not
      * close the stream and block later pushes.
+     *
+     * Because values are discarded after being read, only a single consumer is supported.
+     * Additional consumers will receive a stream lock error. Unread values will be preserved until {@link close} is called.
      */
     [Symbol.asyncIterator](): AsyncIterableIterator<T> {
-        return this.stream.values({ preventCancel: true });
+        return this.#stream.values({ preventCancel: true });
     }
 }

source/sse-session/index.ts

@@ -1,3 +1,4 @@
+export * from './async-push-iterator.ts';
 export * from './types.ts';
 export * from './sse-session.ts';
 export * from './sse-event-parser.ts';

test/sse-session/async-push-iterator.test.ts

@@ -23,18 +23,14 @@ const collectAll = async <T>(iterator: AsyncPushIterator<T>): Promise<T[]> => {
 const testPushComposedPushAndConsume = async (): Promise<void> => {
     const iterator = new AsyncPushIterator<number>();
 
-    const result = new Promise<number[]>((resolve) => {
+    const result = (): Promise<number[]> => collectAll(iterator);
-        void (async (): Promise<void> => {
-            resolve(await collectAll(iterator));
-        })();
-    });
 
     iterator.push(1);
     iterator.push(2);
     iterator.push(3);
     iterator.close();
 
-    await expect(result).resolves.toEqual([ 1, 2, 3 ]);
+    await expect(result()).resolves.toEqual([ 1, 2, 3 ]);
 };
 
 /**
@@ -61,15 +57,11 @@ const testPushComposedBuffersValuesPushedBeforeLoopStarts = async (): Promise<vo
 const testPushComposedResolvesWithNoValues = async (): Promise<void> => {
     const iterator = new AsyncPushIterator<number>();
 
-    const result = new Promise<number[]>((resolve) => {
+    const result = async (): Promise<number[]> => collectAll(iterator);
-        void (async (): Promise<void> => {
-            resolve(await collectAll(iterator));
-        })();
-    });
 
     iterator.close();
 
-    await expect(result).resolves.toEqual([]);
+    await expect(result()).resolves.toEqual([]);
 };
 
 /**
@@ -78,11 +70,7 @@ const testPushComposedResolvesWithNoValues = async (): Promise<void> => {
 const testPushComposedIgnoresValuesAfterClose = async (): Promise<void> => {
     const iterator = new AsyncPushIterator<number>();
 
-    const result = new Promise<number[]>((resolve) => {
+    const result = async (): Promise<number[]> => collectAll(iterator);
-        void (async (): Promise<void> => {
-            resolve(await collectAll(iterator));
-        })();
-    });
 
     iterator.push(1);
     iterator.push(2);
@@ -90,7 +78,7 @@ const testPushComposedIgnoresValuesAfterClose = async (): Promise<void> => {
     iterator.close();
     iterator.push(4);
 
-    await expect(result).resolves.toEqual([ 1, 2, 3 ]);
+    await expect(result()).resolves.toEqual([ 1, 2, 3 ]);
 };
 
 /**
@@ -104,30 +92,19 @@ const testPushComposedRejectsMultipleConsumers = async (): Promise<void> => {
 
     const failureFlag = vi.fn();
 
-    const successfulIterator = (): Promise<number[]> =>
+    const successfulIterator = (): Promise<number[]> => collectAll(iterator);
-        new Promise((resolve) => {
-            void (async (): Promise<void> => {
-                resolve(await collectAll(iterator));
-            })();
-        });
 
-    const failedIterator = (): Promise<void> =>
+    const failedIterator = async (): Promise<void> => {
-        new Promise((resolve, reject) => {
-            void (async (): Promise<void> => {
         try {
             /* eslint-disable-next-line */
             for await (const _value of iterator) {
             }
         } catch (error) {
             failureFlag();
-                    reject(error);
         }
+    };
 
-                resolve();
+    const promises = [ successfulIterator(), failedIterator() ];
-            })();
-        });
-
-    const promises = [ successfulIterator(), failedIterator().catch(() => {}) ];
 
     iterator.close();
 
@@ -175,14 +152,63 @@ const testPushComposedAllowsPushingAfterEarlyBreak = async (): Promise<void> =>
     expect(secondPass).toEqual([ 2, 3 ]);
 };
 
+/**
+ * Tests that the iterator rejects after {@link AsyncPushIterator.error} is called.
+ */
+const testPushIteratorRejectsAfterError = async (): Promise<void> => {
+    const iterator = new AsyncPushIterator<number>();
+
+    iterator.error(new Error('Stream has been closed for a test'));
+
+    await expect(collectAll(iterator)).rejects.toThrow('Stream has been closed for a test');
+};
+
+/**
+ * Tests that the iterator closes the stream when error() is called.
+ */
+const testPushIteratorClosesWhenErrorIsCalled = async (): Promise<void> => {
+    const iterator = new AsyncPushIterator<number>();
+
+    iterator.error(new Error('Stream has been closed for a test'));
+    expect(iterator.closed).toBe(true);
+};
+
+/**
+ * Tests that subsequent calls to error() are ignored.
+ */
+const testPushIteratorIgnoresSubsequentErrorCalls = async (): Promise<void> => {
+    const iterator = new AsyncPushIterator<number>();
+
+    iterator.error(new Error('Stream has been closed for a test'));
+    expect(iterator.closed).toBe(true);
+
+    expect(iterator.error(new Error('Second error'))).toBe(undefined);
+};
+
+/**
+ * Tests that a consumer can check if the iterator is closed.
+ */
+const testPushIteratorCanCheckIfClosed = async (): Promise<void> => {
+    const iterator = new AsyncPushIterator<number>();
+
+    expect(iterator.closed).toBe(false);
+
+    iterator.close();
+    expect(iterator.closed).toBe(true);
+};
+
 const runTests = async (): Promise<void> => {
-    test('AsyncPushIterator (composed): pushes and consumes values', testPushComposedPushAndConsume);
+    test('AsyncPushIterator: pushes and consumes values', testPushComposedPushAndConsume);
-    test('AsyncPushIterator (composed): buffers values pushed before the for-await loop starts', testPushComposedBuffersValuesPushedBeforeLoopStarts);
+    test('AsyncPushIterator: buffers values pushed before the for-await loop starts', testPushComposedBuffersValuesPushedBeforeLoopStarts);
-    test('AsyncPushIterator (composed): resolves with no values when nothing was pushed', testPushComposedResolvesWithNoValues);
+    test('AsyncPushIterator: resolves with no values when nothing was pushed', testPushComposedResolvesWithNoValues);
-    test('AsyncPushIterator (composed): ignores values pushed after close', testPushComposedIgnoresValuesAfterClose);
+    test('AsyncPushIterator: ignores values pushed after close', testPushComposedIgnoresValuesAfterClose);
-    test('AsyncPushIterator (composed): rejects multiple consumers', testPushComposedRejectsMultipleConsumers);
+    test('AsyncPushIterator: rejects multiple consumers', testPushComposedRejectsMultipleConsumers);
-    test('AsyncPushIterator (composed): resolves immediately when closed before the loop starts', testPushComposedResolvesWhenClosedBeforeLoop);
+    test('AsyncPushIterator: resolves immediately when closed before the loop starts', testPushComposedResolvesWhenClosedBeforeLoop);
-    test('AsyncPushIterator (composed): keeps the stream open after an early break', testPushComposedAllowsPushingAfterEarlyBreak);
+    test('AsyncPushIterator: keeps the stream open after an early break', testPushComposedAllowsPushingAfterEarlyBreak);
+    test('AsyncPushIterator: rejects after error', testPushIteratorRejectsAfterError);
+    test('AsyncPushIterator: closes the stream when error() is called', testPushIteratorClosesWhenErrorIsCalled);
+    test('AsyncPushIterator: ignores subsequent error() calls', testPushIteratorIgnoresSubsequentErrorCalls);
+    test('AsyncPushIterator: can check if closed', testPushIteratorCanCheckIfClosed);
 };
 
 await runTests();