fix: throw when type of array values is not defined (#9649)

lib/sequelize.js

@@ -1095,9 +1095,14 @@ class Sequelize {
       type = dialectTypes[type.key].extend(type);
     }
 
-    if (type instanceof DataTypes.ARRAY && dialectTypes[type.type.key]) {
-      type.type = dialectTypes[type.type.key].extend(type.type);
+    if (type instanceof DataTypes.ARRAY) {
+      if (!type.type) {
+        throw new Error('ARRAY is missing type definition for its values.');
+      } else if (dialectTypes[type.type.key]) {
+        type.type = dialectTypes[type.type.key].extend(type.type);
+      }
     }
+
     return type;
   }
 

test/integration/sequelize.test.js

@@ -1206,6 +1206,16 @@ describe(Support.getTestDialectTeaser('Sequelize'), () => {
   });
 
   describe('define', () => {
+    it('raises an error if no values are defined', function() {
+      expect(() => {
+        this.sequelize.define('omnomnom', {
+          bla: { type: DataTypes.ARRAY }
+        });
+      }).to.throw(Error, 'ARRAY is missing type definition for its values.');
+    });
+  });
+
+  describe('define', () => {
     [
       { type: DataTypes.ENUM, values: ['scheduled', 'active', 'finished']},
       DataTypes.ENUM('scheduled', 'active', 'finished')