browserify+espowerifyでassertの結果がおかしくなる件

app001.test-bundle-by-cmd.js

/*
 * browserify -t espowerify ./build/test/e2e/app001.test.js > ./build/test/e2e/app001.test-bundle-by-cmd.js
 */
//...
'use strict';
var assert = require('power-assert');
describe('apptest001', function () {
    it('should raise', function () {
        assert(assert._expr(assert._capt(1 === 0, 'arguments/0'), {
            content: 'assert(1 === 0)',
            filepath: '/tmp/tmpproject/build/test/e2e/app001.test.js',
            line: 7
        }));
    });
});

app001.test-bundle.js

//...
'use strict';
var assert = require('power-assert');
describe('apptest001', function () {
    it('should raise', function () {
        assert(assert._expr(assert._capt(assert._capt(assert, 'arguments/0/callee/object')._expr(assert._capt(assert._capt(assert, 'arguments/0/arguments/0/callee/object')._capt(assert._capt(1 === 0, 'arguments/0/arguments/0/arguments/0'), 'arguments/0'), 'arguments/0/arguments/0'), {
            content: 'assert(1 === 0)',
            filepath: '/tmp/tmpproject/build/test/e2e/app001.test.js',
            line: 7
        }), 'arguments/0'), {
            content: 'assert(assert._expr(assert._capt(1 === 0, \'arguments/0\'), {content: \'assert(1 === 0)\',filepath: \'/tmp/tmpproject/build/test/e2e/app001.test.js\',line: 7}))',
            filepath: '/tmp/tmpproject/build/test/e2e/app001.test.js',
            line: 7
        }));
    });
});

//...

app001.test.js

"use strict";
var assert = require("power-assert");

describe("apptest001", function() {
  it("should raise", function() {
    assert(1 === 0);
  });
});

gulpfile.coffee

gulp = require "gulp"
browserify = require "browserify"
espowerify = require "espowerify"
source = require "vinyl-source-stream"

# Bundle test scripts for browser testing
gulp.task "bundle", ->
  browserify "./build/test/e2e/app001.test.js",
    transform: [ espowerify ]
  .bundle()
  .pipe source("app001.test-bundle.js")
  .pipe gulp.dest "./build/test/e2e"

app001.test.jsが元ファイル
app001.test-bundle-by-cmd.js は正しく出力されている
app001.test-bundle.js は gulpからbrowserify(+espowerify)を実行した結果
（共に関係ない部分は省略）

browserifyのバージョンを最新(9.0.3)にあげたらなおりました
この現象が出たバージョン：8.1.3

ちなみにコマンドラインで適用したbrowserifyのバージョンはglobalのだったのでもっと古かった(5.9.1)