How to concatenate files with the same name using Gulp?

Question

JavaScript

As an example, we have the following directory with JSON files:

test/
  dir1/
    test.json
    test2.json
  dir2/
    test.json
    test2.json

so, here, the essence of the question is how to get the output of the concatenated file test.jsonand, test2.json accordingly.
With plugins for gulp

gulp-foreach

and

gulp-merge-json

I came up with this one:

return gulp.src('test/**/*.json')
        .pipe(foreach((stream, file) => {
            return stream
                .pipe(merge(`${path.basename(file.path)}`));
        }))
        .pipe(gulp.dest(`куданибудь/`));

but the problem is that only the latest files are taken, in this case it would be all files from the dir2.