“use strict”; /* eslint-disable no-new-func */ const acorn = require(“acorn”); const findGlobals = require(“acorn-globals”); const escodegen = require(“escodegen”);

// We can't use the default browserify vm shim because it doesn't work in a web worker.

// From ES spec table of contents. Also, don't forget the Annex B additions. // If someone feels ambitious maybe make this into an npm package. const builtInConsts = [“Infinity”, “NaN”, “undefined”]; const otherBuiltIns = [“eval”, “isFinite”, “isNaN”, “parseFloat”, “parseInt”, “decodeURI”, “decodeURIComponent”,

"encodeURI", "encodeURIComponent", "Array", "ArrayBuffer", "Boolean", "DataView", "Date", "Error", "EvalError",
"Float32Array", "Float64Array", "Function", "Int8Array", "Int16Array", "Int32Array", "Map", "Number", "Object",
"Proxy", "Promise", "RangeError", "ReferenceError", "RegExp", "Set", "String", "Symbol", "SyntaxError", "TypeError",
"Uint8Array", "Uint8ClampedArray", "Uint16Array", "Uint32Array", "URIError", "WeakMap", "WeakSet", "JSON", "Math",
"Reflect", "escape", "unescape"];

exports.createContext = function (sandbox) {

Object.defineProperty(sandbox, "__isVMShimContext", {
  value: true,
  writable: true,
  configurable: true,
  enumerable: false
});

for (const builtIn of builtInConsts) {
  Object.defineProperty(sandbox, builtIn, {
    value: global[builtIn],
    writable: false,
    configurable: false,
    enumerable: false
  });
}

for (const builtIn of otherBuiltIns) {
  Object.defineProperty(sandbox, builtIn, {
    value: global[builtIn],
    writable: true,
    configurable: true,
    enumerable: false
  });
}

};

exports.isContext = function (sandbox) {

return sandbox.__isVMShimContext;

};

exports.runInContext = function (code, contextifiedSandbox, options) {

if (code === "this") {
  // Special case for during window creation.
  return contextifiedSandbox;
}

if (options === undefined) {
  options = {};
}

const comments = [];
const tokens = [];
const ast = acorn.parse(code, {
  allowReturnOutsideFunction: true,
  ranges: true,
  // collect comments in Esprima's format
  onComment: comments,
  // collect token ranges
  onToken: tokens
});

// make sure we keep comments
escodegen.attachComments(ast, comments, tokens);

const globals = findGlobals(ast);
for (let i = 0; i < globals.length; ++i) {
  if (globals[i].name === "window") {
    continue;
  }

  const nodes = globals[i].nodes;
  for (let j = 0; j < nodes.length; ++j) {
    const type = nodes[j].type;
    const name = nodes[j].name;
    nodes[j].type = "MemberExpression";
    nodes[j].property = { name, type };
    nodes[j].computed = false;
    nodes[j].object = {
      name: "window",
      type: "Identifier"
    };
  }
}

const lastNode = ast.body[ast.body.length - 1];
if (lastNode.type === "ExpressionStatement") {
  lastNode.type = "ReturnStatement";
  lastNode.argument = lastNode.expression;
  delete lastNode.expression;
}

const rewrittenCode = escodegen.generate(ast, { comment: true });
const suffix = options.filename !== undefined ? "\n//# sourceURL=" + options.filename : "";

return Function("window", rewrittenCode + suffix).bind(contextifiedSandbox)(contextifiedSandbox);

};