2 files changed, 12 insertions, 18 deletions

diff --git a/cli/rt/11_streams.js b/cli/rt/11_streams.js
index e5a5732e5..7f8af19e2 100644
--- a/cli/rt/11_streams.js
+++ b/cli/rt/11_streams.js
@@ -388,7 +388,7 @@
       let { highWaterMark } = strategy;
       const { type } = underlyingSource;
 
-      if (isUnderlyingByteSource(underlyingSource)) {
+      if (underlyingSource.type == "bytes") {
         if (size !== undefined) {
           throw new RangeError(
             `When underlying source is "bytes", strategy.size must be undefined.`,
@@ -1226,14 +1226,6 @@
     );
   }
 
-  function isUnderlyingByteSource(
-    underlyingSource,
-  ) {
-    const { type } = underlyingSource;
-    const typeString = String(type);
-    return typeString === "bytes";
-  }
-
   function isWritableStream(x) {
     return !(
       typeof x !== "object" ||
diff --git a/cli/rt/26_fetch.js b/cli/rt/26_fetch.js
index 1c1d8c78f..ca36d7ba4 100644
--- a/cli/rt/26_fetch.js
+++ b/cli/rt/26_fetch.js
@@ -5,7 +5,6 @@
   const { notImplemented } = window.__bootstrap.util;
   const { getHeaderValueParams, isTypedArray } = window.__bootstrap.webUtil;
   const { Blob, bytesSymbol: blobBytesSymbol } = window.__bootstrap.blob;
-  const { read } = window.__bootstrap.io;
   const { close } = window.__bootstrap.resources;
   const Body = window.__bootstrap.body;
   const { ReadableStream } = window.__bootstrap.streams;
@@ -283,6 +282,7 @@
         body,
         clientRid,
       );
+      const rid = fetchResponse.bodyRid;
 
       if (
         NULL_BODY_STATUS.includes(fetchResponse.status) ||
@@ -294,25 +294,27 @@
         responseBody = null;
       } else {
         responseBody = new ReadableStream({
+          type: "bytes",
           async pull(controller) {
             try {
-              const b = new Uint8Array(1024 * 32);
-              const result = await read(fetchResponse.bodyRid, b);
-              if (result === null) {
+              const result = await core.jsonOpAsync("op_fetch_read", { rid });
+              if (!result || !result.chunk) {
                 controller.close();
-                return close(fetchResponse.bodyRid);
+                close(rid);
+              } else {
+                // TODO(ry) This is terribly inefficient. Make this zero-copy.
+                const chunk = new Uint8Array(result.chunk);
+                controller.enqueue(chunk);
               }
-
-              controller.enqueue(b.subarray(0, result));
             } catch (e) {
               controller.error(e);
               controller.close();
-              close(fetchResponse.bodyRid);
+              close(rid);
             }
           },
           cancel() {
             // When reader.cancel() is called
-            close(fetchResponse.bodyRid);
+            close(rid);
           },
         });
       }