Change instanceof(Date) to util.types.isDate(Date) (#2862)

* change instanceof to isDate

* use both methods to check for valid Date

* add test for PR 2862

* use only isDate(date) in place of instanceof Date

* Extend compatibility of `isDate` use back to Node 8

* Clean up test

---------

Co-authored-by: Charmander <~@charmander.me>
Reviewed-by: Charmander <~@charmander.me>

packages/pg/lib/utils.js

@@ -2,6 +2,9 @@
 
 const defaults = require('./defaults')
 
+const util = require('util')
+const { isDate } = util.types || util // Node 8 doesn't have `util.types`
+
 function escapeElement(elementRepresentation) {
   const escaped = elementRepresentation.replace(/\\/g, '\\\\').replace(/"/g, '\\"')
 
@@ -60,7 +63,7 @@ const prepareValue = function (val, seen) {
       }
       return buf.slice(val.byteOffset, val.byteOffset + val.byteLength) // Node.js v4 does not support those Buffer.from params
     }
-    if (val instanceof Date) {
+    if (isDate(val)) {
       if (defaults.parseInputDatesAsUTC) {
         return dateToStringUTC(val)
       } else {

packages/pg/test/integration/gh-issues/2862-tests.js

@@ -0,0 +1,23 @@
+'use strict'
+
+const helper = require('../test-helper')
+const assert = require('assert')
+const vm = require('vm')
+
+const suite = new helper.Suite()
+
+suite.testAsync('Handle date objects as Date', async () => {
+  const crossRealmDate = await vm.runInNewContext('new Date()')
+  assert(!(crossRealmDate instanceof Date))
+  const date = new Date(crossRealmDate.getTime())
+  const client = new helper.pg.Client()
+  await client.connect()
+
+  await client.query('CREATE TEMP TABLE foo(bar timestamptz, bar2 timestamptz)')
+  await client.query('INSERT INTO foo(bar, bar2) VALUES($1, $2)', [date, crossRealmDate])
+  const results = await client.query('SELECT * FROM foo')
+  const row = results.rows[0]
+  assert.deepStrictEqual(row.bar, date)
+  assert.deepStrictEqual(row.bar2, date)
+  await client.end()
+})