rollup-plugin-require-context2/src/helper/extract-args.js

rollup-plugin for webpack requrie-context

const Path = require('path');
const { parse } = require('acorn');
const walk = require('acorn-walk');

function stripHeadAndTailChar(str) {
  return str.substring(1, str.length-1);
}

function extract(code) {
  return new Promise((resolve, reject) => {
    const ast = parse(code, {
      sourceType: 'module'
    });
    const res = []
    walk.simple(ast, {
      CallExpression(node) {
        const {
          start,
          end,
          callee,
          arguments: argNodes
        } = node;
        let args = [];
        if (
          callee.type === 'MemberExpression' &&
          callee.object.name === 'require' &&
          callee.property.name === 'context'
        ) {
          args = argNodes.map(a => a.value)
          res.push({
            start,
            end,
            args
          });
        }
      }
    });

    resolve(res);
  });
}

module.exports = async function extractArgs(code, baseDirname) {
  const data = await extract(code);

  return data.map(r => {
    const { start, end, args } = r;
    const [
      rawDirname = '',
      rawRecursive,
      rawRegexp
    ] = args;

    const dirname = Path.join(baseDirname, rawDirname);
    const recursive = rawRecursive;
    const regexp = rawRegexp;

    return {
      dirname,
      recursive,
      regexp,
      start,
      end
    };
  })
}