From 183646a9deb44d8ff861dc9849f9fa3fd3b214ab Mon Sep 17 00:00:00 2001
From: Gabe Gorelick <gabe@catalytic.com>
Date: Fri, 1 Mar 2019 19:19:30 -0600
Subject: [PATCH] feat(types): handle Numbers passed as Objects

This adds support for Number types that aren't represented as
actual Javascript Number instances. For example, BigInt (new in
Node 10), Decimal.js, etc.

Fixes #10491
---
 .eslintrc.json                      |  1 +
 lib/data-types.js                   | 11 +++++++++++
 package.json                        |  1 +
 test/integration/data-types.test.js | 21 +++++++++++++++++++++
 4 files changed, 34 insertions(+)

diff --git a/.eslintrc.json b/.eslintrc.json
index 606c54271d9d..c4d54035b9de 100644
--- a/.eslintrc.json
+++ b/.eslintrc.json
@@ -32,6 +32,7 @@
     "new-cap": [
       "error",
       {
+        "capIsNewExceptionPattern": "^BigInt",
         "properties": false
       }
     ],
diff --git a/lib/data-types.js b/lib/data-types.js
index 5a8e798666c0..34fdb1ef53ca 100644
--- a/lib/data-types.js
+++ b/lib/data-types.js
@@ -214,6 +214,17 @@ NUMBER.prototype.validate = function(value) {
 
   return true;
 };
+NUMBER.prototype._stringify = function _stringify(number) {
+  if (typeof number === 'number' || number === null || number === undefined) {
+    return number;
+  }
+
+  if (typeof number.toString === 'function') {
+    return number.toString();
+  }
+
+  return number;
+};
 Object.defineProperty(NUMBER.prototype, 'UNSIGNED', {
   get() {
     this._unsigned = true;
diff --git a/package.json b/package.json
index 45a5b02b3fef..314ca5d52f85 100644
--- a/package.json
+++ b/package.json
@@ -53,6 +53,7 @@
     "@types/bluebird": "^3.5.26",
     "@types/node": "^10.12.27",
     "@types/validator": "^10.9.0",
+    "big-integer": "^1.6.42",
     "chai": "^4.x",
     "chai-as-promised": "^7.x",
     "chai-datetime": "^1.x",
diff --git a/test/integration/data-types.test.js b/test/integration/data-types.test.js
index c1c357391baf..d2c0188fd2b3 100644
--- a/test/integration/data-types.test.js
+++ b/test/integration/data-types.test.js
@@ -12,6 +12,7 @@ const chai = require('chai'),
   uuid = require('uuid'),
   DataTypes = require('../../lib/data-types'),
   dialect = Support.getTestDialect(),
+  BigInt = require('big-integer'),
   semver = require('semver');
 
 describe(Support.getTestDialectTeaser('DataTypes'), () => {
@@ -227,6 +228,26 @@ describe(Support.getTestDialectTeaser('DataTypes'), () => {
     }
   });
 
+  it('should handle JS BigInt type', function() {
+    const User = this.sequelize.define('user', {
+      age: Sequelize.BIGINT
+    });
+
+    const age = BigInt(Number.MAX_SAFE_INTEGER).add(Number.MAX_SAFE_INTEGER);
+
+    return User.sync({ force: true }).then(() => {
+      return User.create({ age });
+    }).then(user => {
+      expect(BigInt(user.age).toString()).to.equal(age.toString());
+      return User.findAll({
+        where: { age }
+      });
+    }).then(users => {
+      expect(users).to.have.lengthOf(1);
+      expect(BigInt(users[0].age).toString()).to.equal(age.toString());
+    });
+  });
+
   it('calls parse and bindParam for DOUBLE', () => {
     const Type = new Sequelize.DOUBLE();