Fix memory leak, clean up body streams after retry (#651)

Fixes #650

Co-authored-by: Seth Holladay <me@seth-holladay.com>

Author: HaidongPang

.github/workflows/main.yml

@@ -10,7 +10,7 @@ jobs:
       fail-fast: false
       matrix:
         node-version:
-          - 18
+          - 22
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v4

package.json

@@ -86,6 +86,7 @@
 			"@typescript-eslint/no-unsafe-return": "off",
 			"@typescript-eslint/no-unsafe-call": "off",
 			"@typescript-eslint/naming-convention": "off",
+			"@typescript-eslint/no-unnecessary-type-assertion": "off",
 			"n/no-unsupported-features/node-builtins": "off"
 		}
 	},

source/core/Ky.ts

@@ -36,6 +36,8 @@ export class Ky {
 
 			// Delay the fetch so that body method shortcuts can set the Accept header
 			await Promise.resolve();
+			// Before using ky.request, _fetch clones it and saves the clone for future retries to use.
+			// If retry is not needed, close the cloned request's ReadableStream for memory safety.
 			let response = await ky._fetch();
 
 			for (const hook of ky._options.hooks.afterResponse) {
@@ -64,6 +66,11 @@ export class Ky {
 				throw error;
 			}
 
+			// Now that we know a retry is not needed, close the ReadableStream of the cloned request.
+			if (!ky.request.bodyUsed) {
+				await ky.request.body?.cancel();
+			}
+
 			// If `onDownloadProgress` is passed, it uses the stream API internally
 			if (ky._options.onDownloadProgress) {
 				if (typeof ky._options.onDownloadProgress !== 'function') {