Use only null for err if no error

lib/datastore.js

@@ -97,7 +97,7 @@ Datastore.prototype.ensureIndex = function (options, cb) {
   options = options || {};
 
   if (!options.fieldName) { return callback({ missingFieldName: true }); }
-  if (this.indexes[options.fieldName]) { return callback(); }
+  if (this.indexes[options.fieldName]) { return callback(null); }
 
   this.indexes[options.fieldName] = new Index(options);
 
@@ -108,7 +108,7 @@ Datastore.prototype.ensureIndex = function (options, cb) {
     return callback(e);
   }
 
-  return callback();
+  return callback(null);
 };
 
 
@@ -253,7 +253,7 @@ Datastore.prototype._loadDatabase = function (cb) {
   self.datafileSize = 0;
 
   // In-memory only datastore
-  if (self.inMemoryOnly) { return callback(); }
+  if (self.inMemoryOnly) { return callback(null); }
 
   customUtils.ensureDirectoryExists(path.dirname(self.filename), function (err) {
     fs.exists(self.filename, function (exists) {
@@ -336,7 +336,7 @@ Datastore.prototype.persistCachedDatabase = function (cb) {
     toPersist += model.serialize(doc) + '\n';
   });
 
-  if (toPersist.length === 0) { return callback(); }
+  if (toPersist.length === 0) { return callback(null); }
 
   fs.writeFile(this.filename, toPersist, function (err) { return callback(err); });
 };
@@ -355,7 +355,7 @@ Datastore.prototype._persistNewState = function (newDocs, cb) {
     ;
 
   // In-memory only datastore
-  if (self.inMemoryOnly) { return callback(); }
+  if (self.inMemoryOnly) { return callback(null); }
 
   self.datafileSize += newDocs.length;
 
@@ -363,7 +363,7 @@ Datastore.prototype._persistNewState = function (newDocs, cb) {
     toPersist += model.serialize(doc) + '\n';
   });
 
-  if (toPersist.length === 0) { return callback(); }
+  if (toPersist.length === 0) { return callback(null); }
 
   fs.appendFile(self.filename, toPersist, 'utf8', function (err) {
     return callback(err);

package.json

@@ -1,6 +1,6 @@
 {
   "name": "nedb",
-  "version": "0.7.11",
+  "version": "0.7.12",
   "author": {
     "name": "tldr.io",
     "email": "hello@tldr.io"

test/db.test.js

@@ -1528,7 +1528,7 @@ describe('Database', function () {
           d.insert({ a: 2, b: 45 }, function () {
             d.insert({ a: 1, b: 3 }, function () {
               d.ensureIndex({ fieldName: 'b' }, function (err) {
-                assert.isUndefined(err);
+                assert.isNull(err);
 
                 d.ensureIndex({ fieldName: 'a', unique: true }, function (err) {
                   err.errorType.should.equal('uniqueViolated');