Merge pull request #11985 from Snuffleupagus/rm-isEmptyObj

Convert some `Object`s to `Map`s in `ChunkedStreamManager`, and move the `isEmptyObj` helper function to the test utils

src/core/chunked_stream.js

@@ -18,7 +18,6 @@ import {
  arrayByteLength,
  arraysToBytes,
  createPromiseCapability,
- isEmptyObj,
 } from "../shared/util.js";
 import { MissingDataException } from "./core_utils.js";
 
@@ -319,9 +318,9 @@ class ChunkedStreamManager {
 
  this.currRequestId = 0;
 
- this.chunksNeededByRequest = Object.create(null);
- this.requestsByChunk = Object.create(null);
- this.promisesByRequest = Object.create(null);
+ this._chunksNeededByRequest = new Map();
+ this._requestsByChunk = new Map();
+ this._promisesByRequest = new Map();
  this.progressiveDataLength = 0;
  this.aborted = false;
 
@@ -384,29 +383,31 @@ class ChunkedStreamManager {
  _requestChunks(chunks) {
  const requestId = this.currRequestId++;
 
- const chunksNeeded = Object.create(null);
- this.chunksNeededByRequest[requestId] = chunksNeeded;
+ const chunksNeeded = new Set();
+ this._chunksNeededByRequest.set(requestId, chunksNeeded);
  for (const chunk of chunks) {
  if (!this.stream.hasChunk(chunk)) {
- chunksNeeded[chunk] = true;
+ chunksNeeded.add(chunk);
  }
  }
 
- if (isEmptyObj(chunksNeeded)) {
+ if (chunksNeeded.size === 0) {
  return Promise.resolve();
  }
 
  const capability = createPromiseCapability();
- this.promisesByRequest[requestId] = capability;
+ this._promisesByRequest.set(requestId, capability);
 
  const chunksToRequest = [];
- for (let chunk in chunksNeeded) {
- chunk = chunk | 0;
- if (!(chunk in this.requestsByChunk)) {
- this.requestsByChunk[chunk] = [];
+ for (const chunk of chunksNeeded) {
+ let requestIds = this._requestsByChunk.get(chunk);
+ if (!requestIds) {
+ requestIds = [];
+ this._requestsByChunk.set(chunk, requestIds);
+
  chunksToRequest.push(chunk);
  }
- this.requestsByChunk[chunk].push(requestId);
+ requestIds.push(requestId);
  }
 
  if (!chunksToRequest.length) {
@@ -522,16 +523,19 @@ class ChunkedStreamManager {
  const loadedRequests = [];
  for (let curChunk = beginChunk; curChunk < endChunk; ++curChunk) {
  // The server might return more chunks than requested.
- const requestIds = this.requestsByChunk[curChunk] || [];
- delete this.requestsByChunk[curChunk];
+ const requestIds = this._requestsByChunk.get(curChunk);
+ if (!requestIds) {
+ continue;
+ }
+ this._requestsByChunk.delete(curChunk);
 
  for (const requestId of requestIds) {
- const chunksNeeded = this.chunksNeededByRequest[requestId];
- if (curChunk in chunksNeeded) {
- delete chunksNeeded[curChunk];
+ const chunksNeeded = this._chunksNeededByRequest.get(requestId);
+ if (chunksNeeded.has(curChunk)) {
+ chunksNeeded.delete(curChunk);
  }
 
- if (!isEmptyObj(chunksNeeded)) {
+ if (chunksNeeded.size > 0) {
  continue;
  }
  loadedRequests.push(requestId);
@@ -540,7 +544,7 @@ class ChunkedStreamManager {
 
  // If there are no pending requests, automatically fetch the next
  // unfetched chunk of the PDF file.
- if (!this.disableAutoFetch && isEmptyObj(this.requestsByChunk)) {
+ if (!this.disableAutoFetch && this._requestsByChunk.size === 0) {
  let nextEmptyChunk;
  if (this.stream.numChunksLoaded === 1) {
  // This is a special optimization so that after fetching the first
@@ -559,8 +563,8 @@ class ChunkedStreamManager {
  }
 
  for (const requestId of loadedRequests) {
- const capability = this.promisesByRequest[requestId];
- delete this.promisesByRequest[requestId];
+ const capability = this._promisesByRequest.get(requestId);
+ this._promisesByRequest.delete(requestId);
  capability.resolve();
  }
 
@@ -587,8 +591,8 @@ class ChunkedStreamManager {
  if (this.pdfNetworkStream) {
  this.pdfNetworkStream.cancelAllRequests(reason);
  }
- for (const requestId in this.promisesByRequest) {
- this.promisesByRequest[requestId].reject(reason);
+ for (const [, capability] of this._promisesByRequest) {
+ capability.reject(reason);
  }
  }
 }

src/shared/util.js

@@ -793,13 +793,6 @@ function utf8StringToString(str) {
  return unescape(encodeURIComponent(str));
 }
 
-function isEmptyObj(obj) {
- for (const key in obj) {
- return false;
- }
- return true;
-}
-
 function isBool(v) {
  return typeof v === "boolean";
 }
@@ -931,7 +924,6 @@ export {
  isArrayBuffer,
  isArrayEqual,
  isBool,
- isEmptyObj,
  isNum,
  isString,
  isSameOrigin,

test/unit/metadata_spec.js

@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-import { isEmptyObj } from "../../src/shared/util.js";
+import { isEmptyObj } from "./test_utils.js";
 import { Metadata } from "../../src/display/metadata.js";
 
 describe("metadata", function () {

test/unit/test_utils.js

@@ -175,6 +175,14 @@ function createIdFactory(pageIndex) {
  return page.idFactory;
 }
 
+function isEmptyObj(obj) {
+ assert(
+ typeof obj === "object" && obj !== null,
+ "isEmptyObj - invalid argument."
+ );
+ return Object.keys(obj).length === 0;
+}
+
 export {
  DOMFileReaderFactory,
  NodeFileReaderFactory,
@@ -184,4 +192,5 @@ export {
  buildGetDocumentParams,
  TEST_PDFS_PATH,
  createIdFactory,
+ isEmptyObj,
 };

test/unit/util_spec.js

@@ -19,7 +19,6 @@ import {
  createValidAbsoluteUrl,
  isArrayBuffer,
  isBool,
- isEmptyObj,
  isNum,
  isSameOrigin,
  isString,
@@ -89,16 +88,6 @@ describe("util", function () {
  });
  });
 
- describe("isEmptyObj", function () {
- it("handles empty objects", function () {
- expect(isEmptyObj({})).toEqual(true);
- });
-
- it("handles non-empty objects", function () {
- expect(isEmptyObj({ foo: "bar" })).toEqual(false);
- });
- });
-
  describe("isNum", function () {
  it("handles numeric values", function () {
  expect(isNum(1)).toEqual(true);