refactor: use default parameters

.esdoc.json

@@ -54,6 +54,7 @@
             "./docs/resources.md",
             "./docs/typescript.md",
             "./docs/upgrade-to-v5.md",
+            "./docs/upgrade-to-v6.md",
             "./docs/legacy.md",
             "./docs/whos-using.md",
             "./docs/legal.md"

README.md

@@ -20,9 +20,9 @@ Sequelize follows [SEMVER](http://semver.org). Supports Node v6 and above to use
 
 New to Sequelize? Take a look at the [Tutorials and Guides](http://docs.sequelizejs.com/). You might also be interested in the [API Reference](http://docs.sequelizejs.com/identifiers).
 
-## v5 Release
+## v6 Release
 
-You can find the upgrade guide and changelog [here](http://docs.sequelizejs.com/manual/upgrade-to-v5.html).
+You can find the upgrade guide and changelog [here](http://docs.sequelizejs.com/manual/upgrade-to-v6.html).
 
 ## Table of Contents
 - [Installation](#installation)
@@ -33,7 +33,7 @@ You can find the upgrade guide and changelog [here](http://docs.sequelizejs.com/
 ## Installation
 
 ```bash
-$ npm install --save sequelize # This will install v5
+$ npm install --save sequelize # This will install v6
 
 # And one of the following:
 $ npm install --save pg pg-hstore # Postgres
@@ -44,7 +44,8 @@ $ npm install --save tedious # Microsoft SQL Server
 ```
 
 ## Documentation
-- [v5 Documentation](http://docs.sequelizejs.com)
+- [v6 Documentation](http://docs.sequelizejs.com)
+- [v5 Documentation](https://github.com/sequelize/sequelize/blob/v5/docs)
 - [v4 Documentation](https://github.com/sequelize/sequelize/blob/v4/docs)
 - [v3 Documentation](https://sequelize.readthedocs.io/en/v3/)
 - [Contributing](https://github.com/sequelize/sequelize/blob/master/CONTRIBUTING.md)

docs/upgrade-to-v6.md

-# Upgrade to v5
+# Upgrade to v6
 
-Sequelize v5 is the next major release after v4
+Sequelize v6 is the next major release after v4
 
 ## Breaking Changes
 

lib/associations/belongs-to-many.js

@@ -376,8 +376,8 @@ class BelongsToMany extends Association {
    *
    * @returns {Promise<Array<Model>>}
    */
-  get(instance, options) {
-    options = Utils.cloneDeep(options) || {};
+  get(instance, options = {}) {
+    options = Utils.cloneDeep(options);
 
     const through = this.through;
     let scopeWhere;
@@ -514,9 +514,7 @@ class BelongsToMany extends Association {
    *
    * @returns {Promise}
    */
-  set(sourceInstance, newAssociatedObjects, options) {
-    options = options || {};
-
+  set(sourceInstance, newAssociatedObjects, options = {}) {
     const sourceKey = this.source.primaryKeyAttribute;
     const targetKey = this.target.primaryKeyAttribute;
     const identifier = this.identifier;
@@ -625,21 +623,20 @@ class BelongsToMany extends Association {
 
     options = { ...options };
 
-    const association = this;
-    const sourceKey = association.source.primaryKeyAttribute;
-    const targetKey = association.target.primaryKeyAttribute;
-    const identifier = association.identifier;
-    const foreignIdentifier = association.foreignIdentifier;
+    const sourceKey = this.source.primaryKeyAttribute;
+    const targetKey = this.target.primaryKeyAttribute;
+    const identifier = this.identifier;
+    const foreignIdentifier = this.foreignIdentifier;
     const defaultAttributes = options.through || {};
 
-    newInstances = association.toInstanceArray(newInstances);
+    newInstances = this.toInstanceArray(newInstances);
 
     const where = {
       [identifier]: sourceInstance.get(sourceKey),
       [foreignIdentifier]: newInstances.map(newInstance => newInstance.get(targetKey))
     };
 
-    Object.assign(where, association.through.scope);
+    Object.assign(where, this.through.scope);
 
     const updateAssociations = currentRows => {
       const promises = [];
@@ -651,7 +648,7 @@ class BelongsToMany extends Association {
         if (!existingAssociation) {
           unassociatedObjects.push(obj);
         } else {
-          const throughAttributes = obj[association.through.model.name];
+          const throughAttributes = obj[this.through.model.name];
           const attributes = { ...defaultAttributes, ...throughAttributes };
 
           if (Object.keys(attributes).some(attribute => attributes[attribute] !== existingAssociation[attribute])) {
@@ -662,23 +659,23 @@ class BelongsToMany extends Association {
 
       if (unassociatedObjects.length > 0) {
         const bulk = unassociatedObjects.map(unassociatedObject => {
-          const throughAttributes = unassociatedObject[association.through.model.name];
+          const throughAttributes = unassociatedObject[this.through.model.name];
           return {
             ...defaultAttributes,
             ...throughAttributes,
             [identifier]: sourceInstance.get(sourceKey),
             [foreignIdentifier]: unassociatedObject.get(targetKey),
-            ...association.through.scope
+            ...this.through.scope
           };
         });
 
-        promises.push(association.through.model.bulkCreate(bulk, Object.assign({ validate: true }, options)));
+        promises.push(this.through.model.bulkCreate(bulk, Object.assign({ validate: true }, options)));
       }
 
       for (const assoc of changedAssociations) {
-        const attributes = { ...defaultAttributes, ...assoc[association.through.model.name] };
+        const attributes = { ...defaultAttributes, ...assoc[this.through.model.name] };
 
-        promises.push(association.through.model.update(attributes, Object.assign(options, {
+        promises.push(this.through.model.update(attributes, Object.assign(options, {
           where: {
             [identifier]: sourceInstance.get(sourceKey),
             [foreignIdentifier]: assoc.get(targetKey)
@@ -689,7 +686,7 @@ class BelongsToMany extends Association {
       return Utils.Promise.all(promises);
     };
 
-    return association.through.model.findAll({ ...options, where, raw: true })
+    return this.through.model.findAll({ ...options, where, raw: true })
       .then(currentRows => updateAssociations(currentRows))
       .then(([associations]) => associations)
       .catch(error => {
@@ -707,19 +704,15 @@ class BelongsToMany extends Association {
    *
    * @returns {Promise}
    */
-  remove(sourceInstance, oldAssociatedObjects, options) {
-    const association = this;
-
-    options = options || {};
-
-    oldAssociatedObjects = association.toInstanceArray(oldAssociatedObjects);
+  remove(sourceInstance, oldAssociatedObjects, options = {}) {
+    oldAssociatedObjects = this.toInstanceArray(oldAssociatedObjects);
 
     const where = {
-      [association.identifier]: sourceInstance.get(association.source.primaryKeyAttribute),
-      [association.foreignIdentifier]: oldAssociatedObjects.map(newInstance => newInstance.get(association.target.primaryKeyAttribute))
+      [this.identifier]: sourceInstance.get(this.source.primaryKeyAttribute),
+      [this.foreignIdentifier]: oldAssociatedObjects.map(newInstance => newInstance.get(this.target.primaryKeyAttribute))
     };
 
-    return association.through.model.destroy({ ...options, where });
+    return this.through.model.destroy({ ...options, where });
   }
 
   /**
@@ -732,28 +725,23 @@ class BelongsToMany extends Association {
    *
    * @returns {Promise}
    */
-  create(sourceInstance, values, options) {
-    const association = this;
-
-    options = options || {};
-    values = values || {};
-
+  create(sourceInstance, values = {}, options = {}) {
     if (Array.isArray(options)) {
       options = {
         fields: options
       };
     }
 
-    if (association.scope) {
-      Object.assign(values, association.scope);
+    if (this.scope) {
+      Object.assign(values, this.scope);
       if (options.fields) {
-        options.fields = options.fields.concat(Object.keys(association.scope));
+        options.fields = options.fields.concat(Object.keys(this.scope));
       }
     }
 
     // Create the related model instance
-    return association.target.create(values, options).then(newAssociatedObject =>
-      sourceInstance[association.accessors.add](newAssociatedObject, _.omit(options, ['fields'])).return(newAssociatedObject)
+    return this.target.create(values, options).then(newAssociatedObject =>
+      sourceInstance[this.accessors.add](newAssociatedObject, _.omit(options, ['fields'])).return(newAssociatedObject)
     );
   }
 

lib/associations/belongs-to.js

@@ -225,10 +225,7 @@ class BelongsTo extends Association {
    *
    * @returns {Promise<Model>} The created target model
    */
-  create(sourceInstance, values, options) {
-    values = values || {};
-    options = options || {};
-
+  create(sourceInstance, values = {}, options = {}) {
     return this.target.create(values, options)
       .then(newAssociatedObject => sourceInstance[this.accessors.set](newAssociatedObject, options)
         .then(() => newAssociatedObject)

lib/associations/has-one.js

@@ -244,10 +244,7 @@ class HasOne extends Association {
    *
    * @returns {Promise<Model>} The created target model
    */
-  create(sourceInstance, values, options) {
-    values = values || {};
-    options = options || {};
-
+  create(sourceInstance, values = {}, options = {}) {
     if (this.scope) {
       for (const attribute of Object.keys(this.scope)) {
         values[attribute] = this.scope[attribute];

lib/associations/helpers.js

@@ -52,9 +52,7 @@ exports.addForeignKeyConstraints = addForeignKeyConstraints;
  * @param {Object} aliases Mapping between model and association method names
  *
  */
-function mixinMethods(association, obj, methods, aliases) {
-  aliases = aliases || {};
-
+function mixinMethods(association, obj, methods, aliases = {}) {
   for (const method of methods) {
     // don't override custom methods
     if (!obj.hasOwnProperty(association.accessors[method])) {

lib/dialects/abstract/connection-manager.js

@@ -160,7 +160,7 @@ class ConnectionManager {
     // Apply defaults to each read config
     config.replication.read = config.replication.read.map(readConfig => ({
       ...configWithoutReplication,
-      readConfig
+      ...readConfig
     })
     );
 
@@ -244,8 +244,7 @@ class ConnectionManager {
    *
    * @returns {Promise<Connection>}
    */
-  getConnection(options) {
-    options = options || {};
+  getConnection(options = {}) {
 
     let promise;
     if (this.sequelize.options.databaseVersion === 0) {

lib/dialects/abstract/query-generator.js

@@ -41,9 +41,7 @@ class QueryGenerator {
     this._templateSettings = require('lodash').runInContext().templateSettings;
   }
 
-  extractTableDetails(tableName, options) {
-    options = options || {};
-    tableName = tableName || {};
+  extractTableDetails(tableName = {}, options = {}) {
     return {
       schema: tableName.schema || options.schema || 'public',
       tableName: _.isPlainObject(tableName) ? tableName.tableName : tableName,
@@ -261,10 +259,7 @@ class QueryGenerator {
    *
    * @private
    */
-  bulkInsertQuery(tableName, fieldValueHashes, options, fieldMappedAttributes) {
-    options = options || {};
-    fieldMappedAttributes = fieldMappedAttributes || {};
-
+  bulkInsertQuery(tableName, fieldValueHashes, options = {}, fieldMappedAttributes = {}) {
     const tuples = [];
     const serials = {};
     const allAttributes = [];
@@ -437,7 +432,7 @@ class QueryGenerator {
    * @param {Object} options
    * @param {Object} attributes
    */
-  arithmeticQuery(operator, tableName, attrValueHash, where, options, attributes) {
+  arithmeticQuery(operator, tableName, attrValueHash, where, options, attributes = {}) {
     options = {
       returning: true,
       ...options
@@ -463,7 +458,6 @@ class QueryGenerator {
       values.push(`${this.quoteIdentifier(key)}=${this.quoteIdentifier(key)}${operator} ${this.escape(value)}`);
     }
 
-    attributes = attributes || {};
     for (const key in attributes) {
       const value = attributes[key];
       values.push(`${this.quoteIdentifier(key)}=${this.escape(value)}`);
@@ -491,9 +485,7 @@ class QueryGenerator {
       - rawTablename, the name of the table, without schema. Used to create the name of the index
    @private
   */
-  addIndexQuery(tableName, attributes, options, rawTablename) {
-    options = options || {};
-
+  addIndexQuery(tableName, attributes, options = {}, rawTablename) {
     if (!Array.isArray(attributes)) {
       options = attributes;
       attributes = undefined;
@@ -592,8 +584,7 @@ class QueryGenerator {
     return _.compact(ind).join(' ');
   }
 
-  addConstraintQuery(tableName, options) {
-    options = options || {};
+  addConstraintQuery(tableName, options = {}) {
     const constraintSnippet = this.getConstraintSnippet(tableName, options);
 
     if (typeof tableName === 'string') {
@@ -947,9 +938,7 @@ class QueryGenerator {
     Escape a value (e.g. a string, number or date)
     @private
   */
-  escape(value, field, options) {
-    options = options || {};
-
+  escape(value, field, options = {}) {
     if (value !== null && value !== undefined) {
       if (value instanceof Utils.SequelizeMethod) {
         return this.handleSequelizeMethod(value);
@@ -985,9 +974,7 @@ class QueryGenerator {
     Returns a bind parameter representation of a value (e.g. a string, number or date)
     @private
   */
-  format(value, field, options, bindParam) {
-    options = options || {};
-
+  format(value, field, options = {}, bindParam) {
     if (value !== null && value !== undefined) {
       if (value instanceof Utils.SequelizeMethod) {
         throw new Error('Cannot pass SequelizeMethod as a bind parameter - use escape instead');
@@ -1096,8 +1083,7 @@ class QueryGenerator {
       - offset -> An offset value to start from. Only useable with limit!
    @private
   */
-  selectQuery(tableName, options, model) {
-    options = options || {};
+  selectQuery(tableName, options = {}, model) {
     const limit = options.limit;
     const mainQueryItems = [];
     const subQueryItems = [];
@@ -2445,7 +2431,7 @@ class QueryGenerator {
     Takes something and transforms it into values of a where condition.
    @private
   */
-  getWhereConditions(smth, tableName, factory, options, prepend) {
+  getWhereConditions(smth, tableName, factory, options = {}, prepend = true) {
     const where = {};
 
     if (Array.isArray(tableName)) {
@@ -2455,12 +2441,6 @@ class QueryGenerator {
       }
     }
 
-    options = options || {};
-
-    if (prepend === undefined) {
-      prepend = true;
-    }
-
     if (smth && smth instanceof Utils.SequelizeMethod) { // Checking a property is cheaper than a lot of instanceof calls
       return this.handleSequelizeMethod(smth, tableName, factory, options, prepend);
     }

lib/dialects/abstract/query-generator/helpers/quote.js

@@ -32,10 +32,10 @@ const postgresReservedWords = 'all,analyse,analyze,and,any,array,as,asc,asymmetr
  * @returns {string}
  * @private
  */
-function quoteIdentifier(dialect, identifier, options) {
+function quoteIdentifier(dialect, identifier, options = {}) {
   if (identifier === '*') return identifier;
 
-  options = Utils.defaults(options || {}, {
+  options = Utils.defaults(options, {
     force: false,
     quoteIdentifiers: true
   });

lib/dialects/abstract/query.js

@@ -20,7 +20,7 @@ class AbstractQuery {
       raw: false,
       // eslint-disable-next-line no-console
       logging: console.log
-    }, options || {});
+    }, options);
     this.checkLoggingOption();
   }
 
@@ -44,12 +44,11 @@ class AbstractQuery {
    * @param {Object} [options]
    * @private
    */
-  static formatBindParameters(sql, values, dialect, replacementFunc, options) {
+  static formatBindParameters(sql, values, dialect, replacementFunc, options = {}) {
     if (!values) {
       return [sql, []];
     }
 
-    options = options || {};
     if (typeof replacementFunc !== 'function') {
       options = replacementFunc || {};
       replacementFunc = undefined;

lib/dialects/mariadb/query-generator.js

@@ -8,10 +8,11 @@ const util = require('util');
 class MariaDBQueryGenerator extends MySQLQueryGenerator {
 
   createSchema(schema, options) {
-    options = Object.assign({
+    options = {
       charset: null,
-      collate: null
-    }, options || {});
+      collate: null,
+      ...options
+    };
 
     const charset = options.charset ? ` DEFAULT CHARACTER SET ${this.escape(options.charset)}` : '';
     const collate = options.collate ? ` DEFAULT COLLATE ${this.escape(options.collate)}` : '';

lib/dialects/mssql/query-generator.js

@@ -16,10 +16,10 @@ const throwMethodUndefined = function(methodName) {
 
 class MSSQLQueryGenerator extends AbstractQueryGenerator {
   createDatabaseQuery(databaseName, options) {
-    options = Object.assign({
-      collate: null
-    }, options || {});
-
+    options = {
+      collate: null,
+      ...options
+    };
     const collation = options.collate ? `COLLATE ${this.escape(options.collate)}` : '';
 
     return [
@@ -301,17 +301,13 @@ class MSSQLQueryGenerator extends AbstractQueryGenerator {
     return `EXEC sp_rename '${this.quoteTable(tableName)}.${attrBefore}', '${newName}', 'COLUMN';`;
   }
 
-  bulkInsertQuery(tableName, attrValueHashes, options, attributes) {
+  bulkInsertQuery(tableName, attrValueHashes, options = {}, attributes = {}) {
     const quotedTable = this.quoteTable(tableName);
-    options = options || {};
-    attributes = attributes || {};
 
     const tuples = [];
     const allAttributes = [];
     const allQueries = [];
 
-
-
     let needIdentityInsertWrapper = false,
       outputFragment = '';
 

lib/dialects/mssql/query-interface.js

@@ -20,8 +20,8 @@
 
   @private
  */
-const removeColumn = function(qi, tableName, attributeName, options) {
-  options = Object.assign({ raw: true }, options || {});
+const removeColumn = function(qi, tableName, attributeName, options = {}) {
+  options = Object.assign({ raw: true }, options);
 
   const findConstraintSql = qi.QueryGenerator.getDefaultConstraintQuery(tableName, attributeName);
   return qi.sequelize.query(findConstraintSql, options)

lib/dialects/mysql/query-generator.js

@@ -35,11 +35,11 @@ class MySQLQueryGenerator extends AbstractQueryGenerator {
     });
   }
 
-  createDatabaseQuery(databaseName, options) {
+  createDatabaseQuery(databaseName, options = {}) {
     options = Object.assign({
       charset: null,
       collate: null
-    }, options || {});
+    }, options);
 
     const database = this.quoteIdentifier(databaseName);
     const charset = options.charset ? ` DEFAULT CHARACTER SET ${this.escape(options.charset)}` : '';
@@ -64,12 +64,12 @@ class MySQLQueryGenerator extends AbstractQueryGenerator {
     return 'SELECT VERSION() as `version`';
   }
 
-  createTableQuery(tableName, attributes, options) {
+  createTableQuery(tableName, attributes, options = {}) {
     options = Object.assign({
       engine: 'InnoDB',
       charset: null,
       rowFormat: null
-    }, options || {});
+    }, options);
 
     const primaryKeys = [];
     const foreignKeys = {};
@@ -310,8 +310,8 @@ class MySQLQueryGenerator extends AbstractQueryGenerator {
     return query + limit;
   }
 
-  showIndexesQuery(tableName, options) {
-    return `SHOW INDEX FROM ${this.quoteTable(tableName)}${(options || {}).database ? ` FROM \`${options.database}\`` : ''}`;
+  showIndexesQuery(tableName, options = {}) {
+    return `SHOW INDEX FROM ${this.quoteTable(tableName)}${options.database ? ` FROM \`${options.database}\`` : ''}`;
   }
 
   showConstraintsQuery(table, constraintName) {

lib/dialects/mysql/query-interface.js

@@ -21,9 +21,7 @@ const sequelizeErrors = require('../../errors');
 
  @private
  */
-function removeColumn(qi, tableName, columnName, options) {
-  options = options || {};
-
+function removeColumn(qi, tableName, columnName, options = {}) {
   return qi.sequelize.query(
     qi.QueryGenerator.getForeignKeyQuery(tableName.tableName ? tableName : {
       tableName,

lib/dialects/postgres/query-generator.js

@@ -12,11 +12,11 @@ class PostgresQueryGenerator extends AbstractQueryGenerator {
     return `SET search_path to ${searchPath};`;
   }
 
-  createDatabaseQuery(databaseName, options) {
+  createDatabaseQuery(databaseName, options = {}) {
     options = Object.assign({
       encoding: null,
       collate: null
-    }, options || {});
+    }, options);
 
     const values = {
       database: this.quoteTable(databaseName),
@@ -55,8 +55,8 @@ class PostgresQueryGenerator extends AbstractQueryGenerator {
     return 'SHOW SERVER_VERSION';
   }
 
-  createTableQuery(tableName, attributes, options) {
-    options = Object.assign({}, options || {});
+  createTableQuery(tableName, attributes, options = {}) {
+    options = Object.assign({}, options);
 
     //Postgres 9.0 does not support CREATE TABLE IF NOT EXISTS, 9.1 and above do
     const databaseVersion = _.get(this, 'sequelize.options.databaseVersion', 0);
@@ -109,8 +109,7 @@ class PostgresQueryGenerator extends AbstractQueryGenerator {
     return `CREATE TABLE ${databaseVersion === 0 || semver.gte(databaseVersion, '9.1.0') ? 'IF NOT EXISTS ' : ''}${quotedTable} (${attributesClause})${comments}${columnComments};`;
   }
 
-  dropTableQuery(tableName, options) {
-    options = options || {};
+  dropTableQuery(tableName, options = {}) {
     return `DROP TABLE IF EXISTS ${this.quoteTable(tableName)}${options.cascade ? ' CASCADE' : ''};`;
   }
 
@@ -716,9 +715,7 @@ class PostgresQueryGenerator extends AbstractQueryGenerator {
     }).join(' OR ');
   }
 
-  pgEnumName(tableName, attr, options) {
-    options = options || {};
-
+  pgEnumName(tableName, attr, options = {}) {
     const tableDetails = this.extractTableDetails(tableName, options);
     let enumName = Utils.addTicks(Utils.generateEnumName(tableDetails.tableName, attr), '"');
 
@@ -730,7 +727,7 @@ class PostgresQueryGenerator extends AbstractQueryGenerator {
     return enumName;
   }
 
-  pgListEnums(tableName, attrName, options) {
+  pgListEnums(tableName, attrName, options = {}) {
     let enumName = '';
     const tableDetails = this.extractTableDetails(tableName, options);
 

lib/dialects/sqlite/connection-manager.js

@@ -41,8 +41,7 @@ class ConnectionManager extends AbstractConnectionManager {
     parserStore.clear();
   }
 
-  getConnection(options) {
-    options = options || {};
+  getConnection(options = {}) {
     options.uuid = options.uuid || 'default';
     options.inMemory = (this.sequelize.options.storage || this.sequelize.options.host || ':memory:') === ':memory:' ? 1 : 0;
 

lib/dialects/sqlite/query-generator.js

@@ -20,9 +20,7 @@ class SQLiteQueryGenerator extends MySqlQueryGenerator {
     return 'SELECT sqlite_version() as `version`';
   }
 
-  createTableQuery(tableName, attributes, options) {
-    options = options || {};
-
+  createTableQuery(tableName, attributes, options = {}) {
     const primaryKeys = [];
     const needsMultiplePrimaryKeys = Object.values(attributes).filter(definition => definition.includes('PRIMARY KEY')).length > 1;
     const attrArray = [];

lib/dialects/sqlite/query-interface.js

@@ -26,9 +26,7 @@ const QueryTypes = require('../../query-types');
   @since 1.6.0
   @private
  */
-function removeColumn(qi, tableName, attributeName, options) {
-  options = options || {};
-
+function removeColumn(qi, tableName, attributeName, options = {}) {
   return qi.describeTable(tableName, options).then(fields => {
     delete fields[attributeName];
 
@@ -54,10 +52,8 @@ exports.removeColumn = removeColumn;
   @since 1.6.0
   @private
  */
-function changeColumn(qi, tableName, attributes, options) {
+function changeColumn(qi, tableName, attributes, options = {}) {
   const attributeName = Object.keys(attributes)[0];
-  options = options || {};
-
   return qi.describeTable(tableName, options).then(fields => {
     fields[attributeName] = attributes[attributeName];
 
@@ -84,9 +80,7 @@ exports.changeColumn = changeColumn;
   @since 1.6.0
   @private
  */
-function renameColumn(qi, tableName, attrNameBefore, attrNameAfter, options) {
-  options = options || {};
-
+function renameColumn(qi, tableName, attrNameBefore, attrNameAfter, options = {}) {
   return qi.describeTable(tableName, options).then(fields => {
     fields[attrNameAfter] = { ...fields[attrNameBefore] };
     delete fields[attrNameBefore];

lib/errors/database/exclusion-constraint-error.js

@@ -6,8 +6,7 @@ const DatabaseError = require('./../database-error');
  * Thrown when an exclusion constraint is violated in the database
  */
 class ExclusionConstraintError extends DatabaseError {
-  constructor(options) {
-    options = options || {};
+  constructor(options = {}) {
     options.parent = options.parent || { sql: '' };
 
     super(options.parent);

lib/errors/database/foreign-key-constraint-error.js

@@ -6,8 +6,7 @@ const DatabaseError = require('./../database-error');
  * Thrown when a foreign key constraint is violated in the database
  */
 class ForeignKeyConstraintError extends DatabaseError {
-  constructor(options) {
-    options = options || {};
+  constructor(options = {}) {
     options.parent = options.parent || { sql: '' };
 
     super(options.parent);

lib/errors/database/unknown-constraint-error.js

@@ -6,8 +6,7 @@ const DatabaseError = require('./../database-error');
  * Thrown when constraint name is not found in the database
  */
 class UnknownConstraintError extends DatabaseError {
-  constructor(options) {
-    options = options || {};
+  constructor(options = {}) {
     options.parent = options.parent || { sql: '' };
 
     super(options.parent);

lib/errors/optimistic-lock-error.js

@@ -6,8 +6,7 @@ const BaseError = require('./base-error');
  * Thrown when attempting to update a stale model instance
  */
 class OptimisticLockError extends BaseError {
-  constructor(options) {
-    options = options || {};
+  constructor(options = {}) {
     options.message = options.message || `Attempting to update a stale model instance: ${options.modelName}`;
     super(options.message);
     this.name = 'SequelizeOptimisticLockError';

lib/errors/validation/unique-constraint-error.js

@@ -6,8 +6,7 @@ const ValidationError = require('./../validation-error');
  * Thrown when a unique constraint is violated in the database
  */
 class UniqueConstraintError extends ValidationError {
-  constructor(options) {
-    options = options || {};
+  constructor(options = {}) {
     options.parent = options.parent || { sql: '' };
     options.message = options.message || options.parent.message || 'Validation Error';
     options.errors = options.errors || {};

lib/hooks.js

@@ -79,9 +79,9 @@ const Hooks = {
    * @memberof Sequelize
    * @memberof Sequelize.Model
    */
-  _setupHooks(hooks) {
+  _setupHooks(hooks = {}) {
     this.options.hooks = {};
-    _.map(hooks || {}, (hooksArray, hookName) => {
+    _.map(hooks, (hooksArray, hookName) => {
       if (!Array.isArray(hooksArray)) hooksArray = [hooksArray];
       hooksArray.forEach(hookFn => this.addHook(hookName, hookFn));
     });

lib/model.js

@@ -88,7 +88,7 @@ class Model {
       isNewRecord: true,
       _schema: this.constructor._schema,
       _schemaDelimiter: this.constructor._schemaDelimiter
-    }, options || {});
+    }, options);
 
     if (options.attributes) {
       options.attributes = options.attributes.map(attribute => Array.isArray(attribute) ? attribute[1] : attribute);
@@ -106,7 +106,7 @@ class Model {
     this._previousDataValues = {};
     this._changed = {};
     this._modelOptions = this.constructor.options;
-    this._options = options || {};
+    this._options = options;
 
     /**
      * Returns true if this instance has not yet been persisted to the database
@@ -492,10 +492,9 @@ class Model {
     })(this, includes);
   }
 
-  static _validateIncludedElements(options, tableNames) {
+  static _validateIncludedElements(options, tableNames = {}) {
     if (!options.model) options.model = this;
 
-    tableNames = tableNames || {};
     options.includeNames = [];
     options.includeMap = {};
 
@@ -1868,7 +1867,7 @@ class Model {
       return Promise.resolve(null);
     }
 
-    options = Utils.cloneDeep(options) || {};
+    options = Utils.cloneDeep(options);
 
     if (typeof param === 'number' || typeof param === 'string' || Buffer.isBuffer(param)) {
       options.where = {
@@ -2166,7 +2165,7 @@ class Model {
   static bulkBuild(valueSets, options) {
     options = Object.assign({
       isNewRecord: true
-    }, options || {});
+    }, options);
 
     if (!options.includeValidated) {
       this._conformIncludes(options, this);
@@ -2211,7 +2210,7 @@ class Model {
    *
    */
   static create(values, options) {
-    options = Utils.cloneDeep(options || {});
+    options = Utils.cloneDeep(options);
 
     return this.build(values, {
       isNewRecord: true,
@@ -2437,7 +2436,7 @@ class Model {
       hooks: true,
       returning: false,
       validate: true
-    }, Utils.cloneDeep(options || {}));
+    }, Utils.cloneDeep(options));
 
     options.model = this;
 
@@ -2697,7 +2696,7 @@ class Model {
    * {@link Model.destroy} for more information
    */
   static truncate(options) {
-    options = Utils.cloneDeep(options) || {};
+    options = Utils.cloneDeep(options);
     options.truncate = true;
     return this.destroy(options);
   }
@@ -2813,7 +2812,7 @@ class Model {
     options = Object.assign({
       hooks: true,
       individualHooks: false
-    }, options || {});
+    }, options);
 
     options.type = QueryTypes.RAW;
     options.model = this;
@@ -3165,9 +3164,7 @@ class Model {
    *
    * @returns {Promise<Model[],?number>} returns an array of affected rows and affected count with `options.returning: true`, whenever supported by dialect
    */
-  static increment(fields, options) {
-    options = options || {};
-
+  static increment(fields, options = {}) {
     this._injectScope(options);
     this._optionsMustContainWhere(options);
 
@@ -3986,13 +3983,12 @@ class Model {
    *
    * @returns {Promise<Model>}
    */
-  update(values, options) {
+  update(values, options = {}) {
     // Clone values so it doesn't get modified for caller scope and ignore undefined values
     values = _.omitBy(values, value => value === undefined);
 
     const changedBefore = this.changed() || [];
 
-    options = options || {};
     if (Array.isArray(options)) options = { fields: options };
 
     options = Utils.cloneDeep(options);

lib/query-interface.js

@@ -37,8 +37,7 @@ class QueryInterface {
    *
    * @returns {Promise}
    */
-  createDatabase(database, options) {
-    options = options || {};
+  createDatabase(database, options = {}) {
     const sql = this.QueryGenerator.createDatabaseQuery(database, options);
     return this.sequelize.query(sql, options);
   }
@@ -51,8 +50,7 @@ class QueryInterface {
    *
    * @returns {Promise}
    */
-  dropDatabase(database, options) {
-    options = options || {};
+  dropDatabase(database, options = {}) {
     const sql = this.QueryGenerator.dropDatabaseQuery(database);
     return this.sequelize.query(sql, options);
   }
@@ -65,8 +63,7 @@ class QueryInterface {
    *
    * @returns {Promise}
    */
-  createSchema(schema, options) {
-    options = options || {};
+  createSchema(schema, options = {}) {
     const sql = this.QueryGenerator.createSchema(schema);
     return this.sequelize.query(sql, options);
   }
@@ -79,8 +76,7 @@ class QueryInterface {
    *
    * @returns {Promise}
    */
-  dropSchema(schema, options) {
-    options = options || {};
+  dropSchema(schema, options = {}) {
     const sql = this.QueryGenerator.dropSchema(schema);
     return this.sequelize.query(sql, options);
   }
@@ -92,9 +88,7 @@ class QueryInterface {
    *
    * @returns {Promise}
    */
-  dropAllSchemas(options) {
-    options = options || {};
-
+  dropAllSchemas(options = {}) {
     if (!this.QueryGenerator._dialect.supports.schemas) {
       return this.sequelize.drop(options);
     }
@@ -287,8 +281,7 @@ class QueryInterface {
    *
    * @returns {Promise}
    */
-  dropAllTables(options) {
-    options = options || {};
+  dropAllTables(options = {}) {
     const skip = options.skip || [];
 
     const dropAllTables = tableNames => Promise.each(tableNames, tableName => {
@@ -340,13 +333,11 @@ class QueryInterface {
    * @returns {Promise}
    * @private
    */
-  dropEnum(enumName, options) {
+  dropEnum(enumName, options = {}) {
     if (this.sequelize.getDialect() !== 'postgres') {
       return Promise.resolve();
     }
 
-    options = options || {};
-
     return this.sequelize.query(
       this.QueryGenerator.pgEnumDrop(null, null, this.QueryGenerator.pgEscapeAndQuote(enumName)),
       Object.assign({}, options, { raw: true })
@@ -361,14 +352,12 @@ class QueryInterface {
    * @returns {Promise}
    * @private
    */
-  dropAllEnums(options) {
+  dropAllEnums(options = {}) {
     if (this.sequelize.getDialect() !== 'postgres') {
       return Promise.resolve();
     }
 
-    options = options || {};
-
-    return this.pgListEnums(null, options).map(result => this.sequelize.query(
+    return this.pgListEnums(undefined, options).map(result => this.sequelize.query(
       this.QueryGenerator.pgEnumDrop(null, null, this.QueryGenerator.pgEscapeAndQuote(result.enum_name)),
       Object.assign({}, options, { raw: true })
     ));
@@ -383,8 +372,7 @@ class QueryInterface {
    * @returns {Promise}
    * @private
    */
-  pgListEnums(tableName, options) {
-    options = options || {};
+  pgListEnums(tableName, options = {}) {
     const sql = this.QueryGenerator.pgListEnums(tableName);
     return this.sequelize.query(sql, Object.assign({}, options, { plain: false, raw: true, type: QueryTypes.SELECT }));
   }
@@ -398,8 +386,7 @@ class QueryInterface {
    *
    * @returns {Promise}
    */
-  renameTable(before, after, options) {
-    options = options || {};
+  renameTable(before, after, options = {}) {
     const sql = this.QueryGenerator.renameTableQuery(before, after);
     return this.sequelize.query(sql, options);
   }
@@ -504,12 +491,11 @@ class QueryInterface {
    *
    * @returns {Promise}
    */
-  addColumn(table, key, attribute, options) {
+  addColumn(table, key, attribute, options = {}) {
     if (!table || !key || !attribute) {
       throw new Error('addColumn takes at least 3 arguments (table, attribute name, attribute definition)');
     }
 
-    options = options || {};
     attribute = this.sequelize.normalizeAttribute(attribute);
     return this.sequelize.query(this.QueryGenerator.addColumnQuery(table, key, attribute), options);
   }
@@ -523,8 +509,7 @@ class QueryInterface {
    *
    * @returns {Promise}
    */
-  removeColumn(tableName, attributeName, options) {
-    options = options || {};
+  removeColumn(tableName, attributeName, options = {}) {
     switch (this.sequelize.options.dialect) {
       case 'sqlite':
         // sqlite needs some special treatment as it cannot drop a column
@@ -551,9 +536,8 @@ class QueryInterface {
    *
    * @returns {Promise}
    */
-  changeColumn(tableName, attributeName, dataTypeOrOptions, options) {
+  changeColumn(tableName, attributeName, dataTypeOrOptions, options = {}) {
     const attributes = {};
-    options = options || {};
 
     if (Object.values(DataTypes).includes(dataTypeOrOptions)) {
       attributes[attributeName] = { type: dataTypeOrOptions, allowNull: true };
@@ -586,8 +570,7 @@ class QueryInterface {
    *
    * @returns {Promise}
    */
-  renameColumn(tableName, attrNameBefore, attrNameAfter, options) {
-    options = options || {};
+  renameColumn(tableName, attrNameBefore, attrNameAfter, options = {}) {
     return this.describeTable(tableName, options).then(data => {
       if (!data[attrNameBefore]) {
         throw new Error(`Table ${tableName} doesn't have the column ${attrNameBefore}`);
@@ -678,7 +661,7 @@ class QueryInterface {
       return Promise.resolve({});
     }
 
-    options = Object.assign({}, options || {}, { type: QueryTypes.FOREIGNKEYS });
+    options = Object.assign({}, options, { type: QueryTypes.FOREIGNKEYS });
 
     return Promise.map(tableNames, tableName =>
       this.sequelize.query(this.QueryGenerator.getForeignKeysQuery(tableName, this.sequelize.config.database), options)
@@ -750,8 +733,7 @@ class QueryInterface {
    *
    * @returns {Promise}
    */
-  removeIndex(tableName, indexNameOrAttributes, options) {
-    options = options || {};
+  removeIndex(tableName, indexNameOrAttributes, options = {}) {
     const sql = this.QueryGenerator.removeIndexQuery(tableName, indexNameOrAttributes);
     return this.sequelize.query(sql, options);
   }
@@ -858,8 +840,7 @@ class QueryInterface {
    *
    * @returns {Promise}
    */
-  removeConstraint(tableName, constraintName, options) {
-    options = options || {};
+  removeConstraint(tableName, constraintName, options = {}) {
 
     switch (this.sequelize.options.dialect) {
       case 'mysql':
@@ -1001,7 +982,7 @@ class QueryInterface {
   }
 
   update(instance, tableName, values, identifier, options) {
-    options = { ...options || {} };
+    options = { ...options };
     options.hasTrigger = !!(instance && instance._modelOptions && instance._modelOptions.hasTrigger);
 
     const sql = this.QueryGenerator.updateQuery(tableName, values, identifier, options, instance.constructor.rawAttributes);
@@ -1191,18 +1172,16 @@ class QueryInterface {
     });
   }
 
-  createTrigger(tableName, triggerName, timingType, fireOnArray, functionName, functionParams, optionsArray, options) {
+  createTrigger(tableName, triggerName, timingType, fireOnArray, functionName, functionParams, optionsArray, options = {}) {
     const sql = this.QueryGenerator.createTrigger(tableName, triggerName, timingType, fireOnArray, functionName, functionParams, optionsArray);
-    options = options || {};
     if (sql) {
       return this.sequelize.query(sql, options);
     }
     return Promise.resolve();
   }
 
-  dropTrigger(tableName, triggerName, options) {
+  dropTrigger(tableName, triggerName, options = {}) {
     const sql = this.QueryGenerator.dropTrigger(tableName, triggerName);
-    options = options || {};
 
     if (sql) {
       return this.sequelize.query(sql, options);
@@ -1210,9 +1189,8 @@ class QueryInterface {
     return Promise.resolve();
   }
 
-  renameTrigger(tableName, oldTriggerName, newTriggerName, options) {
+  renameTrigger(tableName, oldTriggerName, newTriggerName, options = {}) {
     const sql = this.QueryGenerator.renameTrigger(tableName, oldTriggerName, newTriggerName);
-    options = options || {};
 
     if (sql) {
       return this.sequelize.query(sql, options);
@@ -1248,9 +1226,8 @@ class QueryInterface {
    *
    * @returns {Promise}
    */
-  createFunction(functionName, params, returnType, language, body, optionsArray, options) {
+  createFunction(functionName, params, returnType, language, body, optionsArray, options = {}) {
     const sql = this.QueryGenerator.createFunction(functionName, params, returnType, language, body, optionsArray);
-    options = options || {};
 
     if (sql) {
       return this.sequelize.query(sql, options);
@@ -1276,9 +1253,8 @@ class QueryInterface {
    *
    * @returns {Promise}
    */
-  dropFunction(functionName, params, options) {
+  dropFunction(functionName, params, options = {}) {
     const sql = this.QueryGenerator.dropFunction(functionName, params);
-    options = options || {};
 
     if (sql) {
       return this.sequelize.query(sql, options);
@@ -1306,9 +1282,8 @@ class QueryInterface {
    *
    * @returns {Promise}
    */
-  renameFunction(oldFunctionName, params, newFunctionName, options) {
+  renameFunction(oldFunctionName, params, newFunctionName, options = {}) {
     const sql = this.QueryGenerator.renameFunction(oldFunctionName, params, newFunctionName);
-    options = options || {};
 
     if (sql) {
       return this.sequelize.query(sql, options);

lib/sequelize.js

@@ -255,7 +255,7 @@ class Sequelize {
       databaseVersion: 0,
       typeValidation: false,
       benchmark: false
-    }, options || {});
+    }, options);
 
     if (!this.options.dialect) {
       throw new Error('Dialect needs to be explicitly supplied as of v4.0.0');

lib/transaction.js

@@ -20,7 +20,7 @@ class Transaction {
    * @param {string} options.isolationLevel=true Sets the isolation level of the transaction.
    * @param {string} options.deferrable Sets the constraints to be deferred or immediately checked.
    */
-  constructor(sequelize, options) {
+  constructor(sequelize, options = {}) {
     this.sequelize = sequelize;
     this.savepoints = [];
     this._afterCommitHooks = [];
@@ -32,7 +32,7 @@ class Transaction {
       type: sequelize.options.transactionType,
       isolationLevel: sequelize.options.isolationLevel,
       readOnly: false
-    }, options || {});
+    }, options);
 
     this.parent = this.options.transaction;
     this.id = this.parent ? this.parent.id : generateTransactionId();

lib/utils.js

@@ -124,8 +124,7 @@ function formatNamedParameters(sql, parameters, dialect) {
 exports.formatNamedParameters = formatNamedParameters;
 
 function cloneDeep(obj) {
-  obj = obj || {};
-  return _.cloneDeepWith(obj, elem => {
+  return _.cloneDeepWith(obj || {}, elem => {
     // Do not try to customize cloning of arrays or POJOs
     if (Array.isArray(elem) || _.isPlainObject(elem)) {
       return undefined;
@@ -295,10 +294,9 @@ function defaultValueSchemable(value) {
 }
 exports.defaultValueSchemable = defaultValueSchemable;
 
-function removeNullValuesFromHash(hash, omitNull, options) {
+function removeNullValuesFromHash(hash, omitNull, options = {}) {
   let result = hash;
 
-  options = options || {};
   options.allowNull = options.allowNull || [];
 
   if (omitNull) {

test/integration/sequelize/deferrable.test.js

@@ -14,9 +14,7 @@ if (!Support.sequelize.dialect.supports.deferrableConstraints) {
 describe(Support.getTestDialectTeaser('Sequelize'), () => {
   describe('Deferrable', () => {
     beforeEach(function() {
-      this.run = function(deferrable, options) {
-        options = options || {};
-
+      this.run = function(deferrable, options = {}) {
         const taskTableName      = options.taskTableName || `tasks_${config.rand()}`;
         const transactionOptions = Object.assign({}, { deferrable: Sequelize.Deferrable.SET_DEFERRED }, options);
         const userTableName      = `users_${config.rand()}`;

test/support.js

@@ -48,8 +48,7 @@ const Support = {
     return Sequelize.Promise.resolve(sequelize);
   },
 
-  createSequelizeInstance(options) {
-    options = options || {};
+  createSequelizeInstance(options = {}) {
     options.dialect = this.getTestDialect();
 
     const config = Config[options.dialect];
@@ -83,8 +82,7 @@ const Support = {
     return config;
   },
 
-  getSequelizeInstance(db, user, pass, options) {
-    options = options || {};
+  getSequelizeInstance(db, user, pass, options = {}) {
     options.dialect = options.dialect || this.getTestDialect();
     return new Sequelize(db, user, pass, options);
   },