Merge pull request #33 from jsr-core/fix-queue

fix: allow falsy values and null in Queue and Stack
jsr-core · Aug 16, 2024 · d4eb54f · d4eb54f
2 parents 7db916b + e2116f7
commit d4eb54f
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Showing 5 changed files with 43 additions and 7 deletions.
diff --git a/deno.lock b/deno.lock
diff --git a/queue.ts b/queue.ts
@@ -17,7 +17,7 @@ import { Notify } from "./notify.ts";
  * assertEquals(await queue.pop(), 3);
  * ```
  */
-export class Queue<T> {
+export class Queue<T extends NonNullable<unknown> | null> {
   #notify = new Notify();
   #items: T[] = [];
 
@@ -52,7 +52,7 @@ export class Queue<T> {
     while (true) {
       signal?.throwIfAborted();
       const value = this.#items.shift();
-      if (value) {
+      if (value !== undefined) {
         return value;
       }
       await this.#notify.notified({ signal });

diff --git a/queue_test.ts b/queue_test.ts
@@ -57,3 +57,21 @@ test("Queue 'pop' with signal already aborted", async () => {
     "Aborted",
   );
 });
+
+test("Queue with falsy value is accepted", async () => {
+  const q = new Queue<number>();
+  const popper = q.pop();
+  assertEquals(await promiseState(popper), "pending");
+  q.push(0);
+  assertEquals(await promiseState(popper), "fulfilled");
+  assertEquals(await popper, 0);
+});
+
+test("Queue with null is accepted", async () => {
+  const q = new Queue<null>();
+  const popper = q.pop();
+  assertEquals(await promiseState(popper), "pending");
+  q.push(null);
+  assertEquals(await promiseState(popper), "fulfilled");
+  assertEquals(await popper, null);
+});
diff --git a/stack.ts b/stack.ts
@@ -19,7 +19,7 @@ import { Notify } from "./notify.ts";
  *
  * @template T The type of items in the stack.
  */
-export class Stack<T> {
+export class Stack<T extends NonNullable<unknown> | null> {
   #notify = new Notify();
   #items: T[] = [];
 
@@ -56,7 +56,7 @@ export class Stack<T> {
     while (true) {
       signal?.throwIfAborted();
       const value = this.#items.pop();
-      if (value) {
+      if (value !== undefined) {
         return value;
       }
       await this.#notify.notified({ signal });

diff --git a/stack_test.ts b/stack_test.ts
@@ -57,3 +57,21 @@ test("Stack 'pop' with signal already aborted", async () => {
     "Aborted",
   );
 });
+
+test("Stack with falsy value is accepted", async () => {
+  const q = new Stack<number>();
+  const popper = q.pop();
+  assertEquals(await promiseState(popper), "pending");
+  q.push(0);
+  assertEquals(await promiseState(popper), "fulfilled");
+  assertEquals(await popper, 0);
+});
+
+test("Stack with null is accepted", async () => {
+  const q = new Stack<null>();
+  const popper = q.pop();
+  assertEquals(await promiseState(popper), "pending");
+  q.push(null);
+  assertEquals(await promiseState(popper), "fulfilled");
+  assertEquals(await popper, null);
+});