decorate.js

var toArray = require("./toArray.js");

var toPropertyKey = require("./toPropertyKey.js");

function _decorate(decorators, factory, superClass, mixins) {
  var api = _getDecoratorsApi();

  if (mixins) {
    for (var i = 0; i < mixins.length; i++) {
      api = mixins[i](api);
    }
  }

  var r = factory(function initialize(O) {
    api.initializeInstanceElements(O, decorated.elements);
  }, superClass);
  var decorated = api.decorateClass(_coalesceClassElements(r.d.map(_createElementDescriptor)), decorators);
  api.initializeClassElements(r.F, decorated.elements);
  return api.runClassFinishers(r.F, decorated.finishers);
}

function _getDecoratorsApi() {
  _getDecoratorsApi = function _getDecoratorsApi() {
    return api;
  };

  var api = {
    elementsDefinitionOrder: [["method"], ["field"]],
    initializeInstanceElements: function initializeInstanceElements(O, elements) {
      ["method", "field"].forEach(function (kind) {
        elements.forEach(function (element) {
          if (element.kind === kind && element.placement === "own") {
            this.defineClassElement(O, element);
          }
        }, this);
      }, this);
    },
    initializeClassElements: function initializeClassElements(F, elements) {
      var proto = F.prototype;
      ["method", "field"].forEach(function (kind) {
        elements.forEach(function (element) {
          var placement = element.placement;

          if (element.kind === kind && (placement === "static" || placement === "prototype")) {
            var receiver = placement === "static" ? F : proto;
            this.defineClassElement(receiver, element);
          }
        }, this);
      }, this);
    },
    defineClassElement: function defineClassElement(receiver, element) {
      var descriptor = element.descriptor;

      if (element.kind === "field") {
        var initializer = element.initializer;
        descriptor = {
          enumerable: descriptor.enumerable,
          writable: descriptor.writable,
          configurable: descriptor.configurable,
          value: initializer === void 0 ? void 0 : initializer.call(receiver)
        };
      }

      Object.defineProperty(receiver, element.key, descriptor);
    },
    decorateClass: function decorateClass(elements, decorators) {
      var newElements = [];
      var finishers = [];
      var placements = {
        "static": [],
        prototype: [],
        own: []
      };
      elements.forEach(function (element) {
        this.addElementPlacement(element, placements);
      }, this);
      elements.forEach(function (element) {
        if (!_hasDecorators(element)) return newElements.push(element);
        var elementFinishersExtras = this.decorateElement(element, placements);
        newElements.push(elementFinishersExtras.element);
        newElements.push.apply(newElements, elementFinishersExtras.extras);
        finishers.push.apply(finishers, elementFinishersExtras.finishers);
      }, this);

      if (!decorators) {
        return {
          elements: newElements,
          finishers: finishers
        };
      }

      var result = this.decorateConstructor(newElements, decorators);
      finishers.push.apply(finishers, result.finishers);
      result.finishers = finishers;
      return result;
    },
    addElementPlacement: function addElementPlacement(element, placements, silent) {
      var keys = placements[element.placement];

      if (!silent && keys.indexOf(element.key) !== -1) {
        throw new TypeError("Duplicated element (" + element.key + ")");
      }

      keys.push(element.key);
    },
    decorateElement: function decorateElement(element, placements) {
      var extras = [];
      var finishers = [];

      for (var decorators = element.decorators, i = decorators.length - 1; i >= 0; i--) {
        var keys = placements[element.placement];
        keys.splice(keys.indexOf(element.key), 1);
        var elementObject = this.fromElementDescriptor(element);
        var elementFinisherExtras = this.toElementFinisherExtras((0, decorators[i])(elementObject) || elementObject);
        element = elementFinisherExtras.element;
        this.addElementPlacement(element, placements);

        if (elementFinisherExtras.finisher) {
          finishers.push(elementFinisherExtras.finisher);
        }

        var newExtras = elementFinisherExtras.extras;

        if (newExtras) {
          for (var j = 0; j < newExtras.length; j++) {
            this.addElementPlacement(newExtras[j], placements);
          }

          extras.push.apply(extras, newExtras);
        }
      }

      return {
        element: element,
        finishers: finishers,
        extras: extras
      };
    },
    decorateConstructor: function decorateConstructor(elements, decorators) {
      var finishers = [];

      for (var i = decorators.length - 1; i >= 0; i--) {
        var obj = this.fromClassDescriptor(elements);
        var elementsAndFinisher = this.toClassDescriptor((0, decorators[i])(obj) || obj);

        if (elementsAndFinisher.finisher !== undefined) {
          finishers.push(elementsAndFinisher.finisher);
        }

        if (elementsAndFinisher.elements !== undefined) {
          elements = elementsAndFinisher.elements;

          for (var j = 0; j < elements.length - 1; j++) {
            for (var k = j + 1; k < elements.length; k++) {
              if (elements[j].key === elements[k].key && elements[j].placement === elements[k].placement) {
                throw new TypeError("Duplicated element (" + elements[j].key + ")");
              }
            }
          }
        }
      }

      return {
        elements: elements,
        finishers: finishers
      };
    },
    fromElementDescriptor: function fromElementDescriptor(element) {
      var obj = {
        kind: element.kind,
        key: element.key,
        placement: element.placement,
        descriptor: element.descriptor
      };
      var desc = {
        value: "Descriptor",
        configurable: true
      };
      Object.defineProperty(obj, Symbol.toStringTag, desc);
      if (element.kind === "field") obj.initializer = element.initializer;
      return obj;
    },
    toElementDescriptors: function toElementDescriptors(elementObjects) {
      if (elementObjects === undefined) return;
      return toArray(elementObjects).map(function (elementObject) {
        var element = this.toElementDescriptor(elementObject);
        this.disallowProperty(elementObject, "finisher", "An element descriptor");
        this.disallowProperty(elementObject, "extras", "An element descriptor");
        return element;
      }, this);
    },
    toElementDescriptor: function toElementDescriptor(elementObject) {
      var kind = String(elementObject.kind);

      if (kind !== "method" && kind !== "field") {
        throw new TypeError('An element descriptor\'s .kind property must be either "method" or' + ' "field", but a decorator created an element descriptor with' + ' .kind "' + kind + '"');
      }

      var key = toPropertyKey(elementObject.key);
      var placement = String(elementObject.placement);

      if (placement !== "static" && placement !== "prototype" && placement !== "own") {
        throw new TypeError('An element descriptor\'s .placement property must be one of "static",' + ' "prototype" or "own", but a decorator created an element descriptor' + ' with .placement "' + placement + '"');
      }

      var descriptor = elementObject.descriptor;
      this.disallowProperty(elementObject, "elements", "An element descriptor");
      var element = {
        kind: kind,
        key: key,
        placement: placement,
        descriptor: Object.assign({}, descriptor)
      };

      if (kind !== "field") {
        this.disallowProperty(elementObject, "initializer", "A method descriptor");
      } else {
        this.disallowProperty(descriptor, "get", "The property descriptor of a field descriptor");
        this.disallowProperty(descriptor, "set", "The property descriptor of a field descriptor");
        this.disallowProperty(descriptor, "value", "The property descriptor of a field descriptor");
        element.initializer = elementObject.initializer;
      }

      return element;
    },
    toElementFinisherExtras: function toElementFinisherExtras(elementObject) {
      var element = this.toElementDescriptor(elementObject);

      var finisher = _optionalCallableProperty(elementObject, "finisher");

      var extras = this.toElementDescriptors(elementObject.extras);
      return {
        element: element,
        finisher: finisher,
        extras: extras
      };
    },
    fromClassDescriptor: function fromClassDescriptor(elements) {
      var obj = {
        kind: "class",
        elements: elements.map(this.fromElementDescriptor, this)
      };
      var desc = {
        value: "Descriptor",
        configurable: true
      };
      Object.defineProperty(obj, Symbol.toStringTag, desc);
      return obj;
    },
    toClassDescriptor: function toClassDescriptor(obj) {
      var kind = String(obj.kind);

      if (kind !== "class") {
        throw new TypeError('A class descriptor\'s .kind property must be "class", but a decorator' + ' created a class descriptor with .kind "' + kind + '"');
      }

      this.disallowProperty(obj, "key", "A class descriptor");
      this.disallowProperty(obj, "placement", "A class descriptor");
      this.disallowProperty(obj, "descriptor", "A class descriptor");
      this.disallowProperty(obj, "initializer", "A class descriptor");
      this.disallowProperty(obj, "extras", "A class descriptor");

      var finisher = _optionalCallableProperty(obj, "finisher");

      var elements = this.toElementDescriptors(obj.elements);
      return {
        elements: elements,
        finisher: finisher
      };
    },
    runClassFinishers: function runClassFinishers(constructor, finishers) {
      for (var i = 0; i < finishers.length; i++) {
        var newConstructor = (0, finishers[i])(constructor);

        if (newConstructor !== undefined) {
          if (typeof newConstructor !== "function") {
            throw new TypeError("Finishers must return a constructor.");
          }

          constructor = newConstructor;
        }
      }

      return constructor;
    },
    disallowProperty: function disallowProperty(obj, name, objectType) {
      if (obj[name] !== undefined) {
        throw new TypeError(objectType + " can't have a ." + name + " property.");
      }
    }
  };
  return api;
}

function _createElementDescriptor(def) {
  var key = toPropertyKey(def.key);
  var descriptor;

  if (def.kind === "method") {
    descriptor = {
      value: def.value,
      writable: true,
      configurable: true,
      enumerable: false
    };
  } else if (def.kind === "get") {
    descriptor = {
      get: def.value,
      configurable: true,
      enumerable: false
    };
  } else if (def.kind === "set") {
    descriptor = {
      set: def.value,
      configurable: true,
      enumerable: false
    };
  } else if (def.kind === "field") {
    descriptor = {
      configurable: true,
      writable: true,
      enumerable: true
    };
  }

  var element = {
    kind: def.kind === "field" ? "field" : "method",
    key: key,
    placement: def["static"] ? "static" : def.kind === "field" ? "own" : "prototype",
    descriptor: descriptor
  };
  if (def.decorators) element.decorators = def.decorators;
  if (def.kind === "field") element.initializer = def.value;
  return element;
}

function _coalesceGetterSetter(element, other) {
  if (element.descriptor.get !== undefined) {
    other.descriptor.get = element.descriptor.get;
  } else {
    other.descriptor.set = element.descriptor.set;
  }
}

function _coalesceClassElements(elements) {
  var newElements = [];

  var isSameElement = function isSameElement(other) {
    return other.kind === "method" && other.key === element.key && other.placement === element.placement;
  };

  for (var i = 0; i < elements.length; i++) {
    var element = elements[i];
    var other;

    if (element.kind === "method" && (other = newElements.find(isSameElement))) {
      if (_isDataDescriptor(element.descriptor) || _isDataDescriptor(other.descriptor)) {
        if (_hasDecorators(element) || _hasDecorators(other)) {
          throw new ReferenceError("Duplicated methods (" + element.key + ") can't be decorated.");
        }

        other.descriptor = element.descriptor;
      } else {
        if (_hasDecorators(element)) {
          if (_hasDecorators(other)) {
            throw new ReferenceError("Decorators can't be placed on different accessors with for " + "the same property (" + element.key + ").");
          }

          other.decorators = element.decorators;
        }

        _coalesceGetterSetter(element, other);
      }
    } else {
      newElements.push(element);
    }
  }

  return newElements;
}

function _hasDecorators(element) {
  return element.decorators && element.decorators.length;
}

function _isDataDescriptor(desc) {
  return desc !== undefined && !(desc.value === undefined && desc.writable === undefined);
}

function _optionalCallableProperty(obj, name) {
  var value = obj[name];

  if (value !== undefined && typeof value !== "function") {
    throw new TypeError("Expected '" + name + "' to be a function");
  }

  return value;
}

module.exports = _decorate, module.exports.__esModule = true, module.exports["default"] = module.exports;