fix: make nodeMajorVersion calculation lazy so that it works in a browser environment

Author: maciasello

lib/cursor/AggregationCursor.js

@@ -39,7 +39,7 @@ const utils = require('../../lib/utils');
 function AggregationCursor(agg) {
   const streamOpts = { objectMode: true };
   // for node < 12 we will emit 'close' event after 'end'
-  if (utils.nodeMajorVersion >= 12) {
+  if (utils.nodeMajorVersion() >= 12) {
     // set autoDestroy=true because on node 12 it's by default false
     // gh-10902 need autoDestroy to destroy correctly and emit 'close' event for node >= 12
     streamOpts.autoDestroy = true;
@@ -95,7 +95,7 @@ AggregationCursor.prototype._read = function() {
           return _this.emit('error', error);
         }
         // for node >= 12 the autoDestroy will emit the 'close' event
-        if (utils.nodeMajorVersion < 12) {
+        if (utils.nodeMajorVersion() < 12) {
           _this.on('end', () => _this.emit('close'));
         }
       });

lib/cursor/QueryCursor.js

@@ -37,7 +37,7 @@ const utils = require('../../lib/utils');
 function QueryCursor(query, options) {
   const streamOpts = { objectMode: true };
   // for node < 12 we will emit 'close' event after 'end'
-  if (utils.nodeMajorVersion >= 12) {
+  if (utils.nodeMajorVersion() >= 12) {
     // set autoDestroy=true because on node 12 it's by default false
     // gh-10902 need autoDestroy to destroy correctly and emit 'close' event for node >= 12
     streamOpts.autoDestroy = true;
@@ -104,7 +104,7 @@ QueryCursor.prototype._read = function() {
           return _this.emit('error', error);
         }
         // for node >= 12 the autoDestroy will emit the 'close' event
-        if (utils.nodeMajorVersion < 12) {
+        if (utils.nodeMajorVersion() < 12) {
           _this.on('end', () => _this.emit('close'));
         }
       });

lib/utils.js

@@ -936,4 +936,6 @@ exports.errorToPOJO = function errorToPOJO(error) {
   return ret;
 };
 
-exports.nodeMajorVersion = parseInt(process.versions.node.split('.')[0], 10);
+exports.nodeMajorVersion = function nodeMajorVersion() {
+  return parseInt(process.versions.node.split('.')[0], 10);
+};