jsx.ts

import { Fork } from "../types";
import es7Def from "./es7";
import typesPlugin from "../lib/types";
import sharedPlugin from "../lib/shared";
import * as N from "../gen/nodes";

export default function (fork: Fork) {
  fork.use(es7Def);

  var types = fork.use(typesPlugin);
  var def = types.Type.def;
  var or = types.Type.or;
  var defaults = fork.use(sharedPlugin).defaults;

  def("JSXAttribute")
    .bases("Node")
    .build("name", "value")
    .field("name", or(def("JSXIdentifier"), def("JSXNamespacedName")))
    .field("value", or(
      def("Literal"), // attr="value"
      def("JSXExpressionContainer"), // attr={value}
      null // attr= or just attr
    ), defaults["null"]);

  def("JSXIdentifier")
    .bases("Identifier")
    .build("name")
    .field("name", String);

  def("JSXNamespacedName")
    .bases("Node")
    .build("namespace", "name")
    .field("namespace", def("JSXIdentifier"))
    .field("name", def("JSXIdentifier"));

  def("JSXMemberExpression")
    .bases("MemberExpression")
    .build("object", "property")
    .field("object", or(def("JSXIdentifier"), def("JSXMemberExpression")))
    .field("property", def("JSXIdentifier"))
    .field("computed", Boolean, defaults.false);

  var JSXElementName = or(
    def("JSXIdentifier"),
    def("JSXNamespacedName"),
    def("JSXMemberExpression")
  );

  def("JSXSpreadAttribute")
    .bases("Node")
    .build("argument")
    .field("argument", def("Expression"));

  var JSXAttributes = [or(
    def("JSXAttribute"),
    def("JSXSpreadAttribute")
  )];

  def("JSXExpressionContainer")
    .bases("Expression")
    .build("expression")
    .field("expression", def("Expression"));

  def("JSXElement")
    .bases("Expression")
    .build("openingElement", "closingElement", "children")
    .field("openingElement", def("JSXOpeningElement"))
    .field("closingElement", or(def("JSXClosingElement"), null), defaults["null"])
    .field("children", [or(
      def("JSXElement"),
      def("JSXExpressionContainer"),
      def("JSXFragment"),
      def("JSXText"),
      def("Literal") // TODO Esprima should return JSXText instead.
    )], defaults.emptyArray)
    .field("name", JSXElementName, function (this: N.JSXElement) {
      // Little-known fact: the `this` object inside a default function
      // is none other than the partially-built object itself, and any
      // fields initialized directly from builder function arguments
      // (like openingElement, closingElement, and children) are
      // guaranteed to be available.
      return this.openingElement.name;
    }, true) // hidden from traversal
    .field("selfClosing", Boolean, function (this: N.JSXElement) {
      return this.openingElement.selfClosing;
    }, true) // hidden from traversal
    .field("attributes", JSXAttributes, function (this: N.JSXElement) {
      return this.openingElement.attributes;
    }, true); // hidden from traversal

  def("JSXOpeningElement")
    .bases("Node") // TODO Does this make sense? Can't really be an JSXElement.
    .build("name", "attributes", "selfClosing")
    .field("name", JSXElementName)
    .field("attributes", JSXAttributes, defaults.emptyArray)
    .field("selfClosing", Boolean, defaults["false"]);

  def("JSXClosingElement")
    .bases("Node") // TODO Same concern.
    .build("name")
    .field("name", JSXElementName);

  def("JSXFragment")
    .bases("Expression")
    .build("openingElement", "closingElement", "children")
    .field("openingElement", def("JSXOpeningFragment"))
    .field("closingElement", def("JSXClosingFragment"))
    .field("children", [or(
      def("JSXElement"),
      def("JSXExpressionContainer"),
      def("JSXFragment"),
      def("JSXText"),
      def("Literal") // TODO Esprima should return JSXText instead.
    )], defaults.emptyArray)

  def("JSXOpeningFragment")
    .bases("Node") // TODO Same concern.
    .build();

  def("JSXClosingFragment")
    .bases("Node") // TODO Same concern.
    .build();

  def("JSXText")
    .bases("Literal")
    .build("value")
    .field("value", String);

  def("JSXEmptyExpression").bases("Expression").build();

  // This PR has caused many people issues, but supporting it seems like a
  // good idea anyway: https://github.com/babel/babel/pull/4988
  def("JSXSpreadChild")
    .bases("Expression")
    .build("expression")
    .field("expression", def("Expression"));
};