koa-node-jscover/index.js

koa middleware for instrument code using node-jscover

var fs = require('fs');
var Path = require('path');
var cwd = process.cwd();

module.exports = function (option) {
  var jscover = option.jscover;
  var originalFileLoader = option.originalFileLoader;
  return function *(next) {
    var path = this.path;
    var originalSrc = path.match(/\/node-jscover\/lib\/front-end\/original-src\/(.+)/);
    if (originalSrc) {
      var srcPath = Path.join(cwd, originalSrc[1]);
      this.set('Content-Type', 'application/javascript;charset=utf-8');
      if (!fs.existsSync(srcPath)) {
        srcPath = srcPath.replace(/\.js$/, '.jsx');
      }
      if (originalFileLoader) {
        originalFileLoader(this, srcPath);
      } else {
        this.body = fs.readFileSync(srcPath, {
          encoding: 'utf-8'
        });
      }
      return;
    }
    var pathname;
    if (this.url.match(/-coverage\.js/)) {
      pathname = this.path.replace(/-coverage/, '');
    }
    if (!pathname) {
      yield *next;
      return;
    }
    var codeFile = Path.join(cwd, pathname);
    var name = pathname.substring(1);
    this.set('Content-Type', 'application/javascript;charset=utf-8');
    var content = this.body;
    if (!content) {
      if (!fs.existsSync(codeFile)) {
        codeFile = codeFile.replace(/\.js$/, '.jsx');
      }
      content = fs.readFileSync(codeFile, {
        encoding: 'utf-8'
      });
    }
    if (!option.onlyLoad || !option.onlyLoad.call(this)) {
      content = jscover.instrument(content, name, {
        excludeHeader: true
      });
    }
    this.body = content;
    if (option.next && option.next.call(this)) {
      yield *next;
    }
  };
};