signed app not working for react native android

Hi, I’ve cloned clean project and tried to generate signed apk using instruction from react native docs. Apk is generated but app crashes immediately after running it on device.

react-native-cli@0.1.8 node version : v5.2.0 tested on Samsung GT-P3110 (android 4.2.2/api level 17)

error logs from logcat:

01-07 23:02:37.127 13195-13212/? E/ReactNativeJS: undefined is not a function (evaluating 'babelHelpers.jsx(i["default"],{})')
01-07 23:02:37.143 13195-13213/? E/AndroidRuntime: FATAL EXCEPTION: mqt_native_modules
                                                   com.facebook.react.modules.core.JavascriptException: <unknown>
                                                       index.android.bundle:1:12596
                                                   r
                                                       index.android.bundle:1:575
                                                   a
                                                       index.android.bundle:1:241
                                                   <unknown>
                                                       index.android.bundle:1:11402
                                                   r
                                                       index.android.bundle:1:575
                                                   r
                                                       index.android.bundle:1:304
                                                   a
                                                       index.android.bundle:1:241
                                                   <unknown>
                                                       global [e-mail]:59:28893
01-07 23:02:37.166 457-480/? E/SurfaceFlinger: #### captureScreenImplLocked
01-07 23:02:37.260 13195-13212/? E/ReactNativeJS: undefined is not a function (evaluating 'babelHelpers.jsx(d,{})')
01-07 23:02:37.268 13195-13212/? E/ReactNativeJS: undefined is not an object (evaluating 'n[a]')
01-07 23:02:37.494 469-530/? E/android.os.Debug: !@Dumpstate > dumpstate -k -t -z -d -o /data/log/dumpstate_app_error
01-07 23:02:45.557 13195-13212/? E/ReactNativeJS: Requiring module "AppRegistry" which threw an exception
01-07 23:02:45.565 13195-13212/? E/ReactNativeJS: undefined is not an object (evaluating 'n[a]')

thanks for any help

[amish-patel]

Oh well - this is a result of changes from Babel 5 to 6, I believe. If you generate the helpers manually using instructions at http://stackoverflow.com/questions/33703919/how-to-use-babel-6-external-helpers-in-the-browser and then require it in the code, it all works fine - even on the signed app.

Some more details about the changes. http://www.2ality.com/2015/12/babel6-helpersstandard-library.html

Not sure where to plug in the babel-plugin-external-helpers plugin(babel-plugin-external-helpers-2 was renamed to babel-plugin-external-helpers)! Tried couple of options but didn’t help. Maybe somebody here can find the right place for it in the sequence.

The generated helper file-

(function (global) {
  var babelHelpers = global.babelHelpers = {};
  babelHelpers.typeof = typeof Symbol === "function" && typeof Symbol.iterator === "symbol" ? function (obj) {
    return typeof obj;
  } : function (obj) {
    return obj && typeof Symbol === "function" && obj.constructor === Symbol ? "symbol" : typeof obj;
  };

  babelHelpers.jsx = function () {
    var REACT_ELEMENT_TYPE = typeof Symbol === "function" && Symbol.for && Symbol.for("react.element") || 0xeac7;
    return function createRawReactElement(type, props, key, children) {
      var defaultProps = type && type.defaultProps;
      var childrenLength = arguments.length - 3;

      if (!props && childrenLength !== 0) {
        props = {};
      }

      if (props && defaultProps) {
        for (var propName in defaultProps) {
          if (props[propName] === void 0) {
            props[propName] = defaultProps[propName];
          }
        }
      } else if (!props) {
        props = defaultProps || {};
      }

      if (childrenLength === 1) {
        props.children = children;
      } else if (childrenLength > 1) {
        var childArray = Array(childrenLength);

        for (var i = 0; i < childrenLength; i++) {
          childArray[i] = arguments[i + 3];
        }

        props.children = childArray;
      }

      return {
        $$typeof: REACT_ELEMENT_TYPE,
        type: type,
        key: key === undefined ? null : '' + key,
        ref: null,
        props: props,
        _owner: null
      };
    };
  }();

  babelHelpers.asyncToGenerator = function (fn) {
    return function () {
      var gen = fn.apply(this, arguments);
      return new Promise(function (resolve, reject) {
        function step(key, arg) {
          try {
            var info = gen[key](arg);
            var value = info.value;
          } catch (error) {
            reject(error);
            return;
          }

          if (info.done) {
            resolve(value);
          } else {
            return Promise.resolve(value).then(function (value) {
              return step("next", value);
            }, function (err) {
              return step("throw", err);
            });
          }
        }

        return step("next");
      });
    };
  };

  babelHelpers.classCallCheck = function (instance, Constructor) {
    if (!(instance instanceof Constructor)) {
      throw new TypeError("Cannot call a class as a function");
    }
  };

  babelHelpers.createClass = 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);
      }
    }

    return function (Constructor, protoProps, staticProps) {
      if (protoProps) defineProperties(Constructor.prototype, protoProps);
      if (staticProps) defineProperties(Constructor, staticProps);
      return Constructor;
    };
  }();

  babelHelpers.defineEnumerableProperties = function (obj, descs) {
    for (var key in descs) {
      var desc = descs[key];
      desc.configurable = desc.enumerable = true;
      if ("value" in desc) desc.writable = true;
      Object.defineProperty(obj, key, desc);
    }

    return obj;
  };

  babelHelpers.defaults = function (obj, defaults) {
    var keys = Object.getOwnPropertyNames(defaults);

    for (var i = 0; i < keys.length; i++) {
      var key = keys[i];
      var value = Object.getOwnPropertyDescriptor(defaults, key);

      if (value && value.configurable && obj[key] === undefined) {
        Object.defineProperty(obj, key, value);
      }
    }

    return obj;
  };

  babelHelpers.defineProperty = function (obj, key, value) {
    if (key in obj) {
      Object.defineProperty(obj, key, {
        value: value,
        enumerable: true,
        configurable: true,
        writable: true
      });
    } else {
      obj[key] = value;
    }

    return obj;
  };

  babelHelpers.extends = Object.assign || function (target) {
    for (var i = 1; i < arguments.length; i++) {
      var source = arguments[i];

      for (var key in source) {
        if (Object.prototype.hasOwnProperty.call(source, key)) {
          target[key] = source[key];
        }
      }
    }

    return target;
  };

  babelHelpers.get = function get(object, property, receiver) {
    if (object === null) object = Function.prototype;
    var desc = Object.getOwnPropertyDescriptor(object, property);

    if (desc === undefined) {
      var parent = Object.getPrototypeOf(object);

      if (parent === null) {
        return undefined;
      } else {
        return get(parent, property, receiver);
      }
    } else if ("value" in desc) {
      return desc.value;
    } else {
      var getter = desc.get;

      if (getter === undefined) {
        return undefined;
      }

      return getter.call(receiver);
    }
  };

  babelHelpers.inherits = function (subClass, superClass) {
    if (typeof superClass !== "function" && superClass !== null) {
      throw new TypeError("Super expression must either be null or a function, not " + typeof superClass);
    }

    subClass.prototype = Object.create(superClass && superClass.prototype, {
      constructor: {
        value: subClass,
        enumerable: false,
        writable: true,
        configurable: true
      }
    });
    if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : subClass.__proto__ = superClass;
  };

  babelHelpers.instanceof = function (left, right) {
    if (right != null && typeof Symbol !== "undefined" && right[Symbol.hasInstance]) {
      return right[Symbol.hasInstance](left);
    } else {
      return left instanceof right;
    }
  };

  babelHelpers.interopRequireDefault = function (obj) {
    return obj && obj.__esModule ? obj : {
      default: obj
    };
  };

  babelHelpers.interopRequireWildcard = function (obj) {
    if (obj && obj.__esModule) {
      return obj;
    } else {
      var newObj = {};

      if (obj != null) {
        for (var key in obj) {
          if (Object.prototype.hasOwnProperty.call(obj, key)) newObj[key] = obj[key];
        }
      }

      newObj.default = obj;
      return newObj;
    }
  };

  babelHelpers.newArrowCheck = function (innerThis, boundThis) {
    if (innerThis !== boundThis) {
      throw new TypeError("Cannot instantiate an arrow function");
    }
  };

  babelHelpers.objectDestructuringEmpty = function (obj) {
    if (obj == null) throw new TypeError("Cannot destructure undefined");
  };

  babelHelpers.objectWithoutProperties = function (obj, keys) {
    var target = {};

    for (var i in obj) {
      if (keys.indexOf(i) >= 0) continue;
      if (!Object.prototype.hasOwnProperty.call(obj, i)) continue;
      target[i] = obj[i];
    }

    return target;
  };

  babelHelpers.possibleConstructorReturn = function (self, call) {
    if (!self) {
      throw new ReferenceError("this hasn't been initialised - super() hasn't been called");
    }

    return call && (typeof call === "object" || typeof call === "function") ? call : self;
  };

  babelHelpers.selfGlobal = typeof global === "undefined" ? self : global;

  babelHelpers.set = function set(object, property, value, receiver) {
    var desc = Object.getOwnPropertyDescriptor(object, property);

    if (desc === undefined) {
      var parent = Object.getPrototypeOf(object);

      if (parent !== null) {
        set(parent, property, value, receiver);
      }
    } else if ("value" in desc && desc.writable) {
      desc.value = value;
    } else {
      var setter = desc.set;

      if (setter !== undefined) {
        setter.call(receiver, value);
      }
    }

    return value;
  };

  babelHelpers.slicedToArray = function () {
    function sliceIterator(arr, i) {
      var _arr = [];
      var _n = true;
      var _d = false;
      var _e = undefined;

      try {
        for (var _i = arr[Symbol.iterator](), _s; !(_n = (_s = _i.next()).done); _n = true) {
          _arr.push(_s.value);

          if (i && _arr.length === i) break;
        }
      } catch (err) {
        _d = true;
        _e = err;
      } finally {
        try {
          if (!_n && _i["return"]) _i["return"]();
        } finally {
          if (_d) throw _e;
        }
      }

      return _arr;
    }

    return function (arr, i) {
      if (Array.isArray(arr)) {
        return arr;
      } else if (Symbol.iterator in Object(arr)) {
        return sliceIterator(arr, i);
      } else {
        throw new TypeError("Invalid attempt to destructure non-iterable instance");
      }
    };
  }();

  babelHelpers.slicedToArrayLoose = function (arr, i) {
    if (Array.isArray(arr)) {
      return arr;
    } else if (Symbol.iterator in Object(arr)) {
      var _arr = [];

      for (var _iterator = arr[Symbol.iterator](), _step; !(_step = _iterator.next()).done;) {
        _arr.push(_step.value);

        if (i && _arr.length === i) break;
      }

      return _arr;
    } else {
      throw new TypeError("Invalid attempt to destructure non-iterable instance");
    }
  };

  babelHelpers.taggedTemplateLiteral = function (strings, raw) {
    return Object.freeze(Object.defineProperties(strings, {
      raw: {
        value: Object.freeze(raw)
      }
    }));
  };

  babelHelpers.taggedTemplateLiteralLoose = function (strings, raw) {
    strings.raw = raw;
    return strings;
  };

  babelHelpers.temporalRef = function (val, name, undef) {
    if (val === undef) {
      throw new ReferenceError(name + " is not defined - temporal dead zone");
    } else {
      return val;
    }
  };

  babelHelpers.temporalUndefined = {};

  babelHelpers.toArray = function (arr) {
    return Array.isArray(arr) ? arr : Array.from(arr);
  };

  babelHelpers.toConsumableArray = function (arr) {
    if (Array.isArray(arr)) {
      for (var i = 0, arr2 = Array(arr.length); i < arr.length; i++) arr2[i] = arr[i];

      return arr2;
    } else {
      return Array.from(arr);
    }
  };
})(typeof global === "undefined" ? self : global);

[marinav]

In my case I solved the issue by deleting /android and /ios folders and running react-native eject command. Indeed, I upgraded RN to 0.49 but didn’t delete these two folders. It was working in dev but not in release mode. I hope it can help someone…good luck !