gulp-sourcemaps 2.1.0，最近发布.这是 GitHub 上的一个问题:https://github.com/floridoo/gulp-源映射/问题/238.我相信它应该很快就会修复，同时您可以将其降级到2.0.x或1.7.x.

It is a bug in gulp-sourcemaps 2.1.0, which has been recently released. Here is an issue for it on GitHub: https://github.com/floridoo/gulp-sourcemaps/issues/238. I believe it should be fixed soon, meanwhile you can downgrade it to 2.0.x or 1.7.x.

更新:感谢 这个 GitHub 评论通过以下步骤使其工作:

Update: Thanks to this GitHub comment I was able to make it work with the following steps:

$ mkdir MyProject
$ cd MyProject
$ npm i gulp-sourcemaps@1.7
$ cd ..
$ react-native init MyProject # answer yes