asciidisco.com/build/node_modules/prepack/lib/evaluators/BinaryExpression.js

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});

exports.default = function (ast, strictCode, env, realm) {
  // evaluate left
  var lref = env.evaluate(ast.left, strictCode);
  var lval = _singletons.Environment.GetValue(realm, lref);

  // evaluate right
  var rref = env.evaluate(ast.right, strictCode);
  var rval = _singletons.Environment.GetValue(realm, rref);

  return computeBinary(realm, ast.operator, lval, rval, ast.left.loc, ast.right.loc, ast.loc);
};

exports.getPureBinaryOperationResultType = getPureBinaryOperationResultType;
exports.computeBinary = computeBinary;

var _index = require("../domains/index.js");

var _errors = require("../errors.js");

var _index2 = require("../values/index.js");

var _singletons = require("../singletons.js");

var _invariant = require("../invariant.js");

var _invariant2 = _interopRequireDefault(_invariant);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

var unknownValueOfOrToString = "might be an object with an unknown valueOf or toString or Symbol.toPrimitive method";

// Returns result type if binary operation is pure (terminates, does not throw exception, does not read or write heap), otherwise undefined.
/**
 * Copyright (c) 2017-present, Facebook, Inc.
 * All rights reserved.
 *
 * This source code is licensed under the BSD-style license found in the
 * LICENSE file in the root directory of this source tree. An additional grant
 * of patent rights can be found in the PATENTS file in the same directory.
 */

function getPureBinaryOperationResultType(realm, op, lval, rval, lloc, rloc) {
  function reportErrorIfNotPure(purityTest, typeIfPure) {
    var leftPure = purityTest(realm, lval);
    var rightPure = purityTest(realm, rval);
    if (leftPure && rightPure) return typeIfPure;
    var loc = !leftPure ? lloc : rloc;
    var error = new _errors.CompilerDiagnostic(unknownValueOfOrToString, loc, "PP0002", "RecoverableError");
    if (realm.handleError(error) === "Recover") {
      // Assume that an unknown value is actually a primitive or otherwise a well behaved object.
      return typeIfPure;
    }
    throw new _errors.FatalError();
  }
  if (op === "+") {
    var ltype = _singletons.To.GetToPrimitivePureResultType(realm, lval);
    var rtype = _singletons.To.GetToPrimitivePureResultType(realm, rval);
    if (ltype === undefined || rtype === undefined) {
      var loc = ltype === undefined ? lloc : rloc;
      var error = new _errors.CompilerDiagnostic(unknownValueOfOrToString, loc, "PP0002", "RecoverableError");
      if (realm.handleError(error) === "Recover") {
        // Assume that the unknown value is actually a primitive or otherwise a well behaved object.
        ltype = lval.getType();
        rtype = rval.getType();
        if (ltype === _index2.StringValue || rtype === _index2.StringValue) return _index2.StringValue;
        if (ltype === _index2.NumberValue && rtype === _index2.NumberValue) return _index2.NumberValue;
        return _index2.Value;
      }
      throw new _errors.FatalError();
    }
    if (ltype === _index2.StringValue || rtype === _index2.StringValue) return _index2.StringValue;
    return _index2.NumberValue;
  } else if (op === "<" || op === ">" || op === ">=" || op === "<=") {
    return reportErrorIfNotPure(_singletons.To.IsToPrimitivePure.bind(_singletons.To), _index2.BooleanValue);
  } else if (op === "!=" || op === "==") {
    var _ltype = lval.getType();
    var _rtype = rval.getType();
    if (_ltype === _index2.NullValue || _ltype === _index2.UndefinedValue || _rtype === _index2.NullValue || _rtype === _index2.UndefinedValue) return _index2.BooleanValue;
    return reportErrorIfNotPure(_singletons.To.IsToPrimitivePure.bind(_singletons.To), _index2.BooleanValue);
  } else if (op === "===" || op === "!==") {
    return _index2.BooleanValue;
  } else if (op === ">>>" || op === "<<" || op === ">>" || op === "&" || op === "|" || op === "^" || op === "**" || op === "%" || op === "/" || op === "*" || op === "-") {
    return reportErrorIfNotPure(_singletons.To.IsToNumberPure.bind(_singletons.To), _index2.NumberValue);
  } else if (op === "in" || op === "instanceof") {
    if (rval.mightNotBeObject()) {
      var _error2 = new _errors.CompilerDiagnostic("might not be an object, hence the " + op + " operator might throw a TypeError", rloc, "PP0003", "RecoverableError");
      if (realm.handleError(_error2) === "Recover") {
        // Assume that the object is actually a well behaved object.
        return _index2.BooleanValue;
      }
      throw new _errors.FatalError();
    }
    if (!rval.mightNotBeObject()) {
      // Simple object won't throw here, aren't proxy objects or typed arrays and do not have @@hasInstance properties.
      if (rval.isSimpleObject()) return _index2.BooleanValue;
    }
    var _error = new _errors.CompilerDiagnostic("might be an object that behaves badly for the " + op + " operator", rloc, "PP0004", "RecoverableError");
    if (realm.handleError(_error) === "Recover") {
      // Assume that the object is actually a well behaved object.
      return _index2.BooleanValue;
    }
    throw new _errors.FatalError();
  }
  (0, _invariant2.default)(false, "unimplemented " + op);
}

function computeBinary(realm, op, lval, rval, lloc, rloc, loc) {
  // partial evaluation shortcut for a particular pattern
  if (realm.useAbstractInterpretation && (op === "==" || op === "===" || op === "!=" || op === "!==")) {
    if (!lval.mightNotBeObject() && (rval instanceof _index2.NullValue || rval instanceof _index2.UndefinedValue) || (lval instanceof _index2.NullValue || lval instanceof _index2.UndefinedValue) && !rval.mightNotBeObject()) {
      return new _index2.BooleanValue(realm, op[0] !== "=");
    }
  }

  if (lval instanceof _index2.AbstractValue || rval instanceof _index2.AbstractValue) {
    // generate error if binary operation might throw or have side effects
    getPureBinaryOperationResultType(realm, op, lval, rval, lloc, rloc);
    return _index2.AbstractValue.createFromBinaryOp(realm, op, lval, rval, loc);
  }

  // ECMA262 12.10.3

  // 5. If Type(rval) is not Object, throw a TypeError exception.
  if (op === "in" && !(rval instanceof _index2.ObjectValue)) {
    throw realm.createErrorThrowCompletion(realm.intrinsics.TypeError);
  }
  (0, _invariant2.default)(lval instanceof _index2.ConcreteValue);
  (0, _invariant2.default)(rval instanceof _index2.ConcreteValue);
  return _index.ValuesDomain.computeBinary(realm, op, lval, rval);
}
//# sourceMappingURL=BinaryExpression.js.map