flow like the river

VISUALIZACION/node_modules/safer-eval/lib/index.js

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+/**
+* @copyright 2017 Commenthol
+* @license MIT
+*/
+'use strict';
+
+function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
+
+function _defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } }
+
+function _createClass(Constructor, protoProps, staticProps) { if (protoProps) _defineProperties(Constructor.prototype, protoProps); if (staticProps) _defineProperties(Constructor, staticProps); return Constructor; }
+
+var vm = require('vm');
+
+var _require = require('./common'),
+    createContext = _require.createContext,
+    allow = _require.allow;
+/**
+* reuse saferEval context
+* @class
+* @example
+* const {SaferEval} = require('safer-eval')
+* const safer = new SaferEval()
+* let res1 = safer.runInContext('new Date('1970-01-01')')
+* let res2 = safer.runInContext('new Date('1970-07-01')')
+*/
+
+
+var SaferEval =
+/*#__PURE__*/
+function () {
+  /**
+  * @param {Object} [context] - allowed context
+  * @param {Object} [options] - options for `vm.runInContext`
+  */
+  function SaferEval(context, options) {
+    _classCallCheck(this, SaferEval);
+
+    // define disallowed objects in context
+    var __context = createContext(); // apply "allowed" context vars
+
+
+    allow(context, __context);
+    this._context = vm.createContext(__context);
+    this._options = options;
+  }
+  /**
+  * @param {String} code - a string containing javascript code
+  * @return {Any} evaluated code
+  */
+
+
+  _createClass(SaferEval, [{
+    key: "runInContext",
+    value: function runInContext(code) {
+      if (typeof code !== 'string') {
+        throw new TypeError('not a string');
+      }
+
+      var src = '(function () {"use strict";\n';
+      src += 'Object.constructor = function () {};\n';
+      src += 'return ' + code + ';\n';
+      src += '})()';
+      return vm.runInContext(src, this._context, this._options);
+    }
+  }]);
+
+  return SaferEval;
+}();
+/**
+* A safer approach for eval. (node)
+*
+* In node the `vm` module is used to sandbox the evaluation of `code`.
+*
+* `context` allows the definition of passed in Objects into the sandbox.
+* Take care, injected `code` can overwrite those passed context props!
+* Check the tests under "harmful context"!
+*
+* @static
+* @throws Error
+* @param {String} code - a string containing javascript code
+* @param {Object} [context] - define globals, properties for evaluation context
+* @return {Any} evaluated code
+* @example
+* var code = `{d: new Date('1970-01-01'), b: new Buffer('data')}`
+* var res = saferEval(code, {Buffer: Buffer})
+* // => toString.call(res.d) = '[object Date]'
+* // => toString.call(res.b) = '[object Buffer]'
+*/
+
+
+function saferEval(code, context) {
+  'use strict';
+
+  return new SaferEval(context).runInContext(code);
+}
+
+module.exports = saferEval;
+module.exports.SaferEval = SaferEval;