io: change Reader interface (#2591)

Instead of returning { nread: number, eof: bool }, read() returns EOF | number.

1 files changed, 6 insertions, 5 deletions

diff --git a/js/xeval.ts b/js/xeval.ts
index f769a2ead..81e79f590 100644
--- a/js/xeval.ts
+++ b/js/xeval.ts
@@ -1,7 +1,7 @@
 import { Buffer } from "./buffer";
 import { stdin } from "./files";
 import { TextEncoder, TextDecoder } from "./text_encoding";
-import { Reader } from "./io";
+import { Reader, EOF } from "./io";
 
 export type XevalFunc = (v: string) => void;
 
@@ -35,12 +35,13 @@ async function* chunks(
   // Record how far we have gone with delimiter matching.
   let nextMatchIndex = 0;
   while (true) {
-    const rr = await reader.read(inspectArr);
-    if (rr.nread < 0) {
+    let result = await reader.read(inspectArr);
+    let rr = result === EOF ? 0 : result;
+    if (rr < 0) {
       // Silently fail.
       break;
     }
-    const sliceRead = inspectArr.subarray(0, rr.nread);
+    const sliceRead = inspectArr.subarray(0, rr);
     // Remember how far we have scanned through inspectArr.
     let nextSliceStartIndex = 0;
     for (let i = 0; i < sliceRead.length; i++) {
@@ -74,7 +75,7 @@ async function* chunks(
     }
     // Write all unprocessed chunk to buffer for future inspection.
     await writeAll(inputBuffer, sliceRead.subarray(nextSliceStartIndex));
-    if (rr.eof) {
+    if (result === EOF) {
       // Flush the remainder unprocessed chunk.
       const lastChunk = inputBuffer.toString();
       yield lastChunk;