gulp.dest with glob gulp.src - making it relative

Question

I have a simple task in gulp that is supposed to transpile js:

function js() {
  return gulp.src('lib/modules/*/source/js/*.js')
    .pipe(babel({
      presets: ['@babel/env']
    }))
    .pipe(gulp.dest((fileVinyl) => {
      return fileVinyl.path.replace('/source/', '/public/').replace(/[^\/]*js$/, '')
    }))
}

exports.default = gulp.parallel(js)

And I have a file structure like this:

lib
- modules
  - module1
    - source
      - js
        - file.js
  - module2
    - source
      - js
        - file.js
  - moduleN (...)

Now, I want it to create files like this:

lib
- modules
  - module1
    - public
      - js
        - file.js
    - source (...)
  - module2
    - public
      - js
        - file.js
    - source (...)
  - moduleN (...)

Of course, the code above doesn't work, it outputs files to folders like lib/modules/module1/public/js/module1/source/js/. Is there any method to force gulp to output the file to a specified path instead for it treating it like a base path for appending its own ideas?

Answer 1

The issue I had here was the wrong base for the file. But as I needed to change it dynamically, I couldn't just set it up in src options. Fortunately, I could change it easily in dest function, where I have the path available:

 .pipe(gulp.dest((fileVinyl) => {
      //changing the base so that it will include the whole path to the file,
      //excluding the filename
      fileVinyl.base = fileVinyl.path.replace(/[^\/]*js$/, '')

      //outputing the file to a /public/ folder instead of /source/,
      //keeping the structure
      return path.relative(process.cwd(), fileVinyl.path.replace('/source/', '/public/').replace(/[^\/]*js$/, ''))
    }))