feat: support allowDiskUse for find commands

NODE-2289

Author: mbroadst

lib/collection.js

@@ -313,6 +313,7 @@ const DEPRECATED_FIND_OPTIONS = ['maxScan', 'fields', 'snapshot'];
  * @param {number} [options.maxAwaitTimeMS] The maximum amount of time for the server to wait on new documents to satisfy a tailable cursor query. Requires `taiable` and `awaitData` to be true
  * @param {boolean} [options.noCursorTimeout] The server normally times out idle cursors after an inactivity period (10 minutes) to prevent excess memory use. Set this option to prevent that.
  * @param {object} [options.collation] Specify collation (MongoDB 3.4 or higher) settings for update operation (see 3.4 documentation for available fields).
+ * @param {boolean} [options.allowDiskUse] Enables writing to temporary files on the server.
  * @param {ClientSession} [options.session] optional session to use for this operation
  * @throws {MongoError}
  * @return {Cursor}
@@ -422,6 +423,10 @@ Collection.prototype.find = deprecateOptions(
       query: selector
     };
 
+    if (typeof options.allowDiskUse === 'boolean') {
+      findCommand.allowDiskUse = options.allowDiskUse;
+    }
+
     // Ensure we use the right await data option
     if (typeof newOptions.awaitdata === 'boolean') {
       newOptions.awaitData = newOptions.awaitdata;

lib/core/wireprotocol/query.js

@@ -100,6 +100,10 @@ function prepareFindCommand(server, ns, cmd, cursorState) {
     sortValue = sortObject;
   }
 
+  if (typeof cmd.allowDiskUse === 'boolean') {
+    findCmd.allowDiskUse = cmd.allowDiskUse;
+  }
+
   if (cmd.sort) findCmd.sort = sortValue;
   if (cmd.fields) findCmd.projection = cmd.fields;
   if (cmd.hint) findCmd.hint = cmd.hint;