Source map in grunt (babel + terser)

Question

I`m using babel & terser in grunt. Both of them generate sourceMaps. Babel has to be executed first, so it's sourceMap should be an inputSoruceMap for terser.

I've found something similar on stackoverflow:

babel: {
    dist: {
        options: {
            sourceMap: true,
            inputSourceMap: grunt.file.readJSON('script.js.map')
        },
        src: [
            'script.js',
        ],
        dest: 'app.js'
    }
}

but it's only one file. In my case I have a list of files:

terser: {
    options: {
        sourceMap: true,
    },
    dist: {
        files: [{
            expand: true,
            cwd: 'build/scripts/',
            src: ['**/*.js'],
            dest: 'build/scripts/'
        }]
    }
}

How to add a source maps in terser in this case? It isn't a single file. It's another file for each script (script_file_name + '.map'). How to do it?