Re-use the getArrayBuffer helper from src/display/fetch_stream.js with PDFNodeStreamReader and PDFNodeStreamRangeReader

Given that the Node.js code uses standard `ReadableStream`s now, see PR 20594, it can use the same `getArrayBuffer` as the Fetch API implementation.

Also, change the `getArrayBuffer` fallback case to an Error (rather than a warning) since that should never actually happen.

Author: Snuffleupagus

src/display/fetch_stream.js

@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-import { AbortException, assert, warn } from "../shared/util.js";
+import { AbortException, assert } from "../shared/util.js";
 import {
   BasePDFStream,
   BasePDFStreamRangeReader,
@@ -58,8 +58,7 @@ function getArrayBuffer(val) {
   if (val instanceof ArrayBuffer) {
     return val;
   }
-  warn(`getArrayBuffer - unexpected data format: ${val}`);
-  return new Uint8Array(val).buffer;
+  throw new Error(`getArrayBuffer - unexpected data: ${val}`);
 }
 
 class PDFFetchStream extends BasePDFStream {
@@ -194,4 +193,4 @@ class PDFFetchStreamRangeReader extends BasePDFStreamRangeReader {
   }
 }
 
-export { PDFFetchStream };
+export { getArrayBuffer, PDFFetchStream };

src/display/node_stream.js

@@ -14,13 +14,14 @@
  */
 /* globals process */
 
-import { AbortException, assert, warn } from "../shared/util.js";
+import { AbortException, assert } from "../shared/util.js";
 import {
   BasePDFStream,
   BasePDFStreamRangeReader,
   BasePDFStreamReader,
 } from "../shared/base_pdf_stream.js";
 import { createResponseError } from "./network_utils.js";
+import { getArrayBuffer } from "./fetch_stream.js";
 
 if (typeof PDFJSDev !== "undefined" && PDFJSDev.test("MOZCENTRAL")) {
   throw new Error(
@@ -44,17 +45,6 @@ function getReadableStream(readStream) {
   return polyfill.makeDefaultReadableStreamFromNodeReadable(readStream);
 }
 
-function getArrayBuffer(val) {
-  if (val instanceof Uint8Array) {
-    return val.buffer;
-  }
-  if (val instanceof ArrayBuffer) {
-    return val;
-  }
-  warn(`getArrayBuffer - unexpected data format: ${val}`);
-  return new Uint8Array(val).buffer;
-}
-
 class PDFNodeStream extends BasePDFStream {
   constructor(source) {
     super(source, PDFNodeStreamReader, PDFNodeStreamRangeReader);