执行hb dest报错

报错如下：
```
internal/streams/legacy.js:57
throw er; // Unhandled stream error in pipe.
^
GulpUglifyError: unable to minify JavaScript
at createError (/usr/local/lib/node_modules/html-bundler/node_modules/gulp-uglify/lib/create-error.js:6:14)
at wrapper (/usr/local/lib/node_modules/html-bundler/node_modules/lodash/_createHybrid.js:87:15)
at trycatch (/usr/local/lib/node_modules/html-bundler/node_modules/gulp-uglify/minifier.js:26:12)
at DestroyableTransform.minify [as _transform] (/usr/local/lib/node_modules/html-bundler/node_modules/gulp-uglify/minifier.js:79:19)
at DestroyableTransform.Transform._read (/usr/local/lib/node_modules/html-bundler/node_modules/through2/node_modules/readable-stream/lib/_stream_transform.js:184:10)
at DestroyableTransform.Transform._write (/usr/local/lib/node_modules/html-bundler/node_modules/through2/node_modules/readable-stream/lib/_stream_transform.js:172:83)
at doWrite (/usr/local/lib/node_modules/html-bundler/node_modules/through2/node_modules/readable-stream/lib/_stream_writable.js:428:64)
at writeOrBuffer (/usr/local/lib/node_modules/html-bundler/node_modules/through2/node_modules/readable-stream/lib/_stream_writable.js:417:5)
at DestroyableTransform.Writable.write (/usr/local/lib/node_modules/html-bundler/node_modules/through2/node_modules/readable-stream/lib/_stream_writable.js:334:11)
at Stream.ondata (internal/streams/legacy.js:15:31)
```
报错原因是html-bundler对某些js语法不支持吗？

Start by reproducing the failure with the `hb dest` command and inspect the JavaScript input passed to `gulp-uglify`. The stack trace identifies `internal/streams/legacy.js` and the bundled `gulp-uglify` minifier, but no source file or test is named. Done means identifying the unsupported input or another cause and adding a verified fix or documented limitation.

Written by the indexing model from the issue text.