Mocha diff shown for thrown Error

index.js

describe('diff', function () {

  it('is shown with no diff', function () {
    var e = new Error();
    e.showDiff = true; // because the showDiff fix is not in a release yet
    throw e;
  });

});

output

$ npm t

> mocha-diff-bug@1.0.0 test .../mocha-diff-bug
> mocha index.js



  diff
    1) is not shown


  0 passing (8ms)
  1 failing

  1) diff is not shown:


      + expected - actual


  Error
      at Context.<anonymous> (.../mocha-diff-bug/index.js:7:13)

package.json

{
  "name": "mocha-diff-bug",
  "version": "1.0.0",
  "main": "index.js",
  "scripts": {
    "test": "mocha index.js"
  },
  "devDependencies": {
    "mocha": "^2.2.1"
  }
}