node/test/sequential/test-deprecation-flags.js

'use strict';
require('../common');
var assert = require('assert');
var execFile = require('child_process').execFile;
var depmod = require.resolve('../fixtures/deprecated.js');
var node = process.execPath;

var depUserland =
    require.resolve('../fixtures/deprecated-userland-function.js');

var normal = [depmod];
var noDep = ['--no-deprecation', depmod];
var traceDep = ['--trace-deprecation', depmod];

execFile(node, normal, function(er, stdout, stderr) {
  console.error('normal: show deprecation warning');
  assert.equal(er, null);
  assert.equal(stdout, '');
  assert(/util\.debug is deprecated/.test(stderr));
  console.log('normal ok');
});

execFile(node, noDep, function(er, stdout, stderr) {
  console.error('--no-deprecation: silence deprecations');
  assert.equal(er, null);
  assert.equal(stdout, '');
  assert.equal(stderr, 'DEBUG: This is deprecated\n');
  console.log('silent ok');
});

execFile(node, traceDep, function(er, stdout, stderr) {
  console.error('--trace-deprecation: show stack');
  assert.equal(er, null);
  assert.equal(stdout, '');
  var stack = stderr.trim().split('\n');
  // just check the top and bottom.
  assert.equal(stack[0],
               'Trace: util.debug is deprecated. Use console.error instead.');
  assert.equal(stack.pop(), 'DEBUG: This is deprecated');
  console.log('trace ok');
});

execFile(node, [depUserland], function(er, stdout, stderr) {
  console.error('normal: testing deprecated userland function');
  assert.equal(er, null);
  assert.equal(stdout, '');
  assert.equal(0, stderr.indexOf('deprecatedFunction is deprecated.'));
  console.error('normal: ok');
});