Bootstrap 4 beta 2 - 由于$ color2，模块构建失败

Question

我从beta更新到beta-2并且在运行npm run dev时导入bootstrap时收到以下错误，如下所示：

@import "~bootstrap/scss/bootstrap";

错误：

ERROR in ./resources/assets/app/sass/vendor.scss
Module build failed: ModuleBuildError: Module build failed:
  @return mix($color-base, $color, $level * $theme-color-interval);
         ^
      Argument `$color-2` of `mix($color-1, $color-2, $weight: 50%)` must be a color

Backtrace:
        node_modules/bootstrap/scss/_functions.scss:85, in function `mix`
        node_modules/bootstrap/scss/_functions.scss:85, in function `theme-color-level`
        node_modules/bootstrap/scss/_tables.scss:96
      in /Users/chrisbreuer/Documents/code/ordering/node_modules/bootstrap/scss/_functions.scss (line 85, column 11)
    at runLoaders (/Users/chrisbreuer/Documents/code/ordering/node_modules/webpack/lib/NormalModule.js:195:19)
    at /Users/chrisbreuer/Documents/code/ordering/node_modules/loader-runner/lib/LoaderRunner.js:364:11
    at /Users/chrisbreuer/Documents/code/ordering/node_modules/loader-runner/lib/LoaderRunner.js:230:18
    at context.callback (/Users/chrisbreuer/Documents/code/ordering/node_modules/loader-runner/lib/LoaderRunner.js:111:13)
    at Object.asyncSassJobQueue.push [as callback] (/Users/chrisbreuer/Documents/code/ordering/node_modules/sass-loader/lib/loader.js:55:13)
    at Object.<anonymous> (/Users/chrisbreuer/Documents/code/ordering/node_modules/async/dist/async.js:2244:31)
    at Object.callback (/Users/chrisbreuer/Documents/code/ordering/node_modules/async/dist/async.js:906:16)
    at options.error (/Users/chrisbreuer/Documents/code/ordering/node_modules/node-sass/lib/index.js:294:32)
 @ multi ./resources/assets/app/js/app.js ./resources/assets/app/sass/app.scss ./resources/assets/app/sass/vendor.scss

ERROR in ./resources/assets/app/sass/vendor.scss
Module build failed: ModuleBuildError: Module build failed:
  @return mix($color-base, $color, $level * $theme-color-interval);
         ^
      Argument `$color-2` of `mix($color-1, $color-2, $weight: 50%)` must be a color

Backtrace:
        node_modules/bootstrap/scss/_functions.scss:85, in function `mix`
        node_modules/bootstrap/scss/_functions.scss:85, in function `theme-color-level`
        node_modules/bootstrap/scss/_tables.scss:96
      in /Users/chrisbreuer/Documents/code/ordering/node_modules/bootstrap/scss/_functions.scss (line 85, column 11)
    at runLoaders (/Users/chrisbreuer/Documents/code/ordering/node_modules/webpack/lib/NormalModule.js:195:19)
    at /Users/chrisbreuer/Documents/code/ordering/node_modules/loader-runner/lib/LoaderRunner.js:364:11
    at /Users/chrisbreuer/Documents/code/ordering/node_modules/loader-runner/lib/LoaderRunner.js:230:18
    at context.callback (/Users/chrisbreuer/Documents/code/ordering/node_modules/loader-runner/lib/LoaderRunner.js:111:13)
    at Object.asyncSassJobQueue.push [as callback] (/Users/chrisbreuer/Documents/code/ordering/node_modules/sass-loader/lib/loader.js:55:13)
    at Object.<anonymous> (/Users/chrisbreuer/Documents/code/ordering/node_modules/async/dist/async.js:2244:31)
    at Object.callback (/Users/chrisbreuer/Documents/code/ordering/node_modules/async/dist/async.js:906:16)
    at options.error (/Users/chrisbreuer/Documents/code/ordering/node_modules/node-sass/lib/index.js:294:32)
 @ ./resources/assets/app/sass/vendor.scss
 @ multi ./resources/assets/app/js/app.js ./resources/assets/app/sass/app.scss ./resources/assets/app/sass/vendor.scss

这是一个引导错误还是我需要采取进一步措施来定义某个地方？我似乎无法找到任何试图追踪它的东西。