Error: Plugin/Preset files are not allowed to export objects, only functions.

[Josema]

package.json
"testbabel": "babel-tape-runner test/es6/*",

npm i --save-dev babel-tape-runner
npm i --save-dev babel-preset-es2015

.babelrc

{
    "presets": ["es2015"]
}

/mnt/c/Users/enzo/drive/projects/dop/node_modules/@babel/core/lib/config/config-descriptors.js:178
    throw new Error(`Plugin/Preset files are not allowed to export objects, only functions. In ${filepath}`);
    ^

Error: Plugin/Preset files are not allowed to export objects, only functions.