findModuleDependencies.js

/* @flow */

import types from 'ast-types';
import { parse } from 'babylon';

const config = {
  "sourceType": "module",
  "plugins": [
    "jsx",
    "flow",
    "objectRestSpread",
    "classProperties",
    "asyncGenerators",
  ],
};

const findModuleDependencies = (code: string): Array<string> => {
  const dependencies: Set<string> = new Set();
  const ast = parse(code, config);

  types.visit(ast, {
    visitImportDeclaration(path) {
      dependencies.add(path.node.source.value);
      this.traverse(path);
    },

    visitCallExpression(path) {
      const { callee, arguments: args } = path.node;

      if (callee.name === 'require' && args[0]) {
        dependencies.add(args[0].value);
      }

      this.traverse(path);
    },
  });

  return Array.from(dependencies);
};

export default findModuleDependencies;