fix(sync): throw when no models defined (#10175)

lib/sequelize.js

@@ -733,6 +733,9 @@ class Sequelize {
         }
       });
 
+      // no models defined, just authenticate
+      if (!models.length) return this.authenticate(options);
+
       return Promise.each(models, model => model.sync(options));
     }).then(() => {
       if (options.hooks) {

test/integration/sequelize.test.js

@@ -965,12 +965,22 @@ describe(Support.getTestDialectTeaser('Sequelize'), () => {
     });
 
     if (dialect !== 'sqlite') {
+      it('fails for incorrect connection even when no models are defined', function() {
+        const sequelize = new Sequelize('cyber_bird', 'user', 'pass', {
+          dialect: this.sequelize.options.dialect
+        });
+
+        return expect(sequelize.sync({force: true})).to.be.rejected;
+      });
+
       it('fails with incorrect database credentials (1)', function() {
         this.sequelizeWithInvalidCredentials = new Sequelize('omg', 'bar', null, _.omit(this.sequelize.options, ['host']));
 
         const User2 = this.sequelizeWithInvalidCredentials.define('User', { name: DataTypes.STRING, bio: DataTypes.TEXT });
 
-        return User2.sync().catch(err => {
+        return User2.sync()
+          .then(() => { expect.fail(); })
+          .catch(err => {
             if (dialect === 'postgres' || dialect === 'postgres-native') {
               assert([
                 'fe_sendauth: no password supplied',
@@ -994,9 +1004,7 @@ describe(Support.getTestDialectTeaser('Sequelize'), () => {
         sequelize.define('Project', {title: Sequelize.STRING});
         sequelize.define('Task', {title: Sequelize.STRING});
 
-        return sequelize.sync({force: true}).catch(err => {
-          expect(err).to.be.ok;
-        });
+        return expect(sequelize.sync({force: true})).to.be.rejected;
       });
 
       it('fails with incorrect database credentials (3)', function() {
@@ -1008,9 +1016,7 @@ describe(Support.getTestDialectTeaser('Sequelize'), () => {
         sequelize.define('Project', {title: Sequelize.STRING});
         sequelize.define('Task', {title: Sequelize.STRING});
 
-        return sequelize.sync({force: true}).catch(err => {
-          expect(err).to.be.ok;
-        });
+        return expect(sequelize.sync({force: true})).to.be.rejected;
       });
 
       it('fails with incorrect database credentials (4)', function() {
@@ -1023,19 +1029,22 @@ describe(Support.getTestDialectTeaser('Sequelize'), () => {
         sequelize.define('Project', {title: Sequelize.STRING});
         sequelize.define('Task', {title: Sequelize.STRING});
 
-        return sequelize.sync({force: true}).catch(err => {
-          expect(err).to.be.ok;
-        });
+        return expect(sequelize.sync({force: true})).to.be.rejected;
       });
 
       it('returns an error correctly if unable to sync a foreign key referenced model', function() {
         this.sequelize.define('Application', {
-          authorID: { type: Sequelize.BIGINT, allowNull: false, references: { model: 'User', key: 'id' } }
+          authorID: {
+            type: Sequelize.BIGINT,
+            allowNull: false,
+            references: {
+              model: 'User',
+              key: 'id'
+            }
+          }
         });
 
-        return this.sequelize.sync().catch(error => {
-          assert.ok(error);
-        });
+        return expect(this.sequelize.sync()).to.be.rejected;
       });
 
       it('handles this dependant foreign key constraints', function() {
@@ -1065,6 +1074,7 @@ describe(Support.getTestDialectTeaser('Sequelize'), () => {
 
         return this.sequelize.sync();
       });
+    }
 
     it('return the sequelize instance after syncing', function() {
       return this.sequelize.sync().then(sequelize => {
@@ -1086,7 +1096,6 @@ describe(Support.getTestDialectTeaser('Sequelize'), () => {
         expect(result).to.deep.equal(block);
       });
     });
-    }
 
     describe("doesn't emit logging when explicitly saying not to", () => {
       afterEach(function() {