node>=v9.9.0, assert should use strict mode

[aladdin-add]

node>=9.9.0

var assert = require('assert'); // invalid, should report an error

var assert = require('assert').strict; // valid

[mysticatea]

Thank you for this issue.

However, this is intentional.
Node.js community intended to deprecate four methods (assert.equal, assert.deepEqual, assert.notDeepEqual, and assert.notEqual) rather than all of the non-strict methods. See the commit.