From f9c2a8d437d1b3c95088dba2758f99d62d0d2ff1 Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Fri, 17 Sep 2021 13:46:47 +0200
Subject: [PATCH] Introduce some optional chaining in the `src/shared/` folder

---
 src/shared/fonts_utils.js     |  2 +-
 src/shared/message_handler.js | 37 ++++++++++++-----------------------
 src/shared/util.js            | 15 ++++----------
 3 files changed, 18 insertions(+), 36 deletions(-)

diff --git a/src/shared/fonts_utils.js b/src/shared/fonts_utils.js
index a909b6405..d2a51698a 100644
--- a/src/shared/fonts_utils.js
+++ b/src/shared/fonts_utils.js
@@ -293,7 +293,7 @@ var Type2Parser = function type2Parser(aFilePath) {
             font.set(token.name, stack.pop());
             break;
           default:
-            if (token.operand && token.operand.length) {
+            if (token.operand?.length) {
               var array = [];
               for (var j = 0; j < token.operand.length; j++) {
                 array.push(stack.pop());
diff --git a/src/shared/message_handler.js b/src/shared/message_handler.js
index 7d8815ad6..894332ac6 100644
--- a/src/shared/message_handler.js
+++ b/src/shared/message_handler.js
@@ -87,7 +87,7 @@ class MessageHandler {
         return;
       }
       if (data.stream) {
-        this._processStreamMessage(data);
+        this.#processStreamMessage(data);
         return;
       }
       if (data.callback) {
@@ -140,7 +140,7 @@ class MessageHandler {
         return;
       }
       if (data.streamId) {
-        this._createStreamSink(data);
+        this.#createStreamSink(data);
         return;
       }
       action(data.data);
@@ -286,10 +286,7 @@ class MessageHandler {
     );
   }
 
-  /**
-   * @private
-   */
-  _createStreamSink(data) {
+  #createStreamSink(data) {
     const streamId = data.streamId,
       sourceName = this.sourceName,
       targetName = data.sourceName,
@@ -388,10 +385,7 @@ class MessageHandler {
     );
   }
 
-  /**
-   * @private
-   */
-  _processStreamMessage(data) {
+  #processStreamMessage(data) {
     const streamId = data.streamId,
       sourceName = this.sourceName,
       targetName = data.sourceName,
@@ -435,7 +429,7 @@ class MessageHandler {
         streamSink.desiredSize = data.desiredSize;
 
         new Promise(function (resolve) {
-          resolve(streamSink.onPull && streamSink.onPull());
+          resolve(streamSink.onPull?.());
         }).then(
           function () {
             comObj.postMessage({
@@ -471,12 +465,12 @@ class MessageHandler {
         }
         streamController.isClosed = true;
         streamController.controller.close();
-        this._deleteStreamController(streamController, streamId);
+        this.#deleteStreamController(streamController, streamId);
         break;
       case StreamKind.ERROR:
         assert(streamController, "error should have stream controller");
         streamController.controller.error(wrapReason(data.reason));
-        this._deleteStreamController(streamController, streamId);
+        this.#deleteStreamController(streamController, streamId);
         break;
       case StreamKind.CANCEL_COMPLETE:
         if (data.success) {
@@ -484,7 +478,7 @@ class MessageHandler {
         } else {
           streamController.cancelCall.reject(wrapReason(data.reason));
         }
-        this._deleteStreamController(streamController, streamId);
+        this.#deleteStreamController(streamController, streamId);
         break;
       case StreamKind.CANCEL:
         if (!streamSink) {
@@ -492,9 +486,7 @@ class MessageHandler {
         }
 
         new Promise(function (resolve) {
-          resolve(
-            streamSink.onCancel && streamSink.onCancel(wrapReason(data.reason))
-          );
+          resolve(streamSink.onCancel?.(wrapReason(data.reason)));
         }).then(
           function () {
             comObj.postMessage({
@@ -524,16 +516,13 @@ class MessageHandler {
     }
   }
 
-  /**
-   * @private
-   */
-  async _deleteStreamController(streamController, streamId) {
+  async #deleteStreamController(streamController, streamId) {
     // Delete the `streamController` only when the start, pull, and cancel
     // capabilities have settled, to prevent `TypeError`s.
     await Promise.allSettled([
-      streamController.startCall && streamController.startCall.promise,
-      streamController.pullCall && streamController.pullCall.promise,
-      streamController.cancelCall && streamController.cancelCall.promise,
+      streamController.startCall?.promise,
+      streamController.pullCall?.promise,
+      streamController.cancelCall?.promise,
     ]);
     delete this.streamControllers[streamId];
   }
diff --git a/src/shared/util.js b/src/shared/util.js
index 42b2163af..ede1ee62c 100644
--- a/src/shared/util.js
+++ b/src/shared/util.js
@@ -393,10 +393,7 @@ function assert(cond, msg) {
 
 // Checks if URLs use one of the allowed protocols, e.g. to avoid XSS.
 function _isValidProtocol(url) {
-  if (!url) {
-    return false;
-  }
-  switch (url.protocol) {
+  switch (url?.protocol) {
     case "http:":
     case "https:":
     case "ftp:":
@@ -427,7 +424,7 @@ function createValidAbsoluteUrl(url, baseUrl = null, options = null) {
         const dots = url.match(/\./g);
         // Avoid accidentally matching a *relative* URL pointing to a file named
         // e.g. "www.pdf" or similar.
-        if (dots && dots.length >= 2) {
+        if (dots?.length >= 2) {
           url = `http://${url}`;
         }
       }
@@ -537,11 +534,7 @@ class AbortException extends BaseException {
 }
 
 function bytesToString(bytes) {
-  if (
-    typeof bytes !== "object" ||
-    bytes === null ||
-    bytes.length === undefined
-  ) {
+  if (typeof bytes !== "object" || bytes?.length === undefined) {
     unreachable("Invalid argument for bytesToString");
   }
   const length = bytes.length;
@@ -954,7 +947,7 @@ function utf8StringToString(str) {
 }
 
 function isArrayBuffer(v) {
-  return typeof v === "object" && v !== null && v.byteLength !== undefined;
+  return typeof v === "object" && v?.byteLength !== undefined;
 }
 
 function isArrayEqual(arr1, arr2) {