fix: Empty Response body returns 0-byte array (#7387)

2 files changed, 11 insertions, 1 deletions

diff --git a/cli/rt/24_body.js b/cli/rt/24_body.js
index a3348907b..f755e2bad 100644
--- a/cli/rt/24_body.js
+++ b/cli/rt/24_body.js
@@ -85,7 +85,7 @@
       const enc = new TextEncoder();
       return enc.encode(bodySource.toString()).buffer;
     } else if (!bodySource) {
-      return null;
+      return new ArrayBuffer(0);
     }
     throw new Error(
       `Body type not implemented: ${bodySource.constructor.name}`,
diff --git a/cli/tests/unit/fetch_test.ts b/cli/tests/unit/fetch_test.ts
index 012ce7b34..4bdb54d9e 100644
--- a/cli/tests/unit/fetch_test.ts
+++ b/cli/tests/unit/fetch_test.ts
@@ -738,6 +738,16 @@ unitTest(function responseRedirect(): void {
   assertEquals(redir.type, "default");
 });
 
+unitTest(async function responseWithoutBody(): Promise<void> {
+  const response = new Response();
+  assertEquals(await response.arrayBuffer(), new ArrayBuffer(0));
+  assertEquals(await response.blob(), new Blob([]));
+  assertEquals(await response.text(), "");
+  await assertThrowsAsync(async () => {
+    await response.json();
+  });
+});
+
 unitTest({ perms: { net: true } }, async function fetchBodyReadTwice(): Promise<
   void
 > {