(WIP) Get rid of _source

src/babel/index.js

@@ -9,20 +9,8 @@ const buildTagger = template(`
       return;
     }
 
-    if (fn.hasOwnProperty("__source")) {
-      return;
-    }
-
-    try {
-      Object.defineProperty(fn, "__source", {
-        enumerable: false,
-        configurable: true,
-        value: {
-          fileName: FILENAME,
-          localName: localName
-        }
-      });
-    } catch (err) {}
+    var id = FILENAME + '#' + localName;
+    __REACT_HOT_LOADER__.set(id, fn);
   }
   REGISTRATIONS
 })();

src/patch.dev.js

@@ -2,34 +2,18 @@
 
 const React = require('react');
 const resolveType = require('./resolveType');
-const { isReactRouterish, extractRouteHandlerComponents } = require('./fixupReactRouter');
 
 if (React.createElement.isPatchedByReactHotLoader) {
   throw new Error('Cannot patch React twice.');
 }
 
 const createElement = React.createElement;
-function patchedCreateElement(type, props, ...args) {
+function patchedCreateElement(type, ...args) {
   // Trick React into rendering a proxy so that
   // its state is preserved when the class changes.
   // This will update the proxy if it's for a known type.
   const resolvedType = resolveType(type);
-  const element = createElement(resolvedType, props, ...args);
-
-  // This is lame but let's focus on shipping.
-  // https://github.com/gaearon/react-hot-loader/issues/249
-  if (isReactRouterish(type)) {
-    // Ideally we want to teach React Router to receive children.
-    // We're not in a perfect world, and a dirty workaround works for now.
-    // https://github.com/reactjs/react-router/issues/2182
-    const resolvedProps = element.props;
-    const routeHandlers = extractRouteHandlerComponents(resolvedProps, resolveType);
-    // Side effect 😱
-    // Force proxies to update since React Router ignores new props.
-    routeHandlers.forEach(resolveType);
-  }
-
-  return element;
+  return createElement(resolvedType, ...args);
 }
 patchedCreateElement.isPatchedByReactHotLoader = true;
 React.createElement = patchedCreateElement;

src/resolveType.js

@@ -1,72 +1,36 @@
 const createProxy = require('react-proxy').default;
 
-let proxies = {};
-let warnedAboutTypes = {};
+let proxiesByID = {};
+let idsByType = new WeakMap();
 
-function setFlag(obj, key) {
-  try {
-    Object.defineProperty(obj, key, {
-      configurable: true,
-      enumerable: false,
-      value: true
-    });
-  } catch (err) {}
-}
+window.__REACT_HOT_LOADER__ = {
+  set(id, component) {
+    idsByType.set(component, id);
+  }
+};
 
 function resolveType(type) {
   // We only care about composite components
   if (!type || typeof type === 'string') {
     return type;
   }
 
-  // If the type is not tagged, return it as is.
-  if (
-    !Object.hasOwnProperty.call(type, '__source') ||
-    !type.__source ||
-    !type.__source.fileName ||
-    !type.__source.localName
-  ) {
-    setFlag(type, '__noSourceFound');
-    return type;
-  }
-
-  // Uniquely identifiy the component in code across reloads.
-  const source = type.__source;
-  const id = source.fileName + '#' + source.localName;
-
-  if (type.hasOwnProperty('__noSourceFound')) {
-    // This component didn't have a source last time, but now it has?
-    // This means createElement() was called during module definition.
-    // Bail out, or the component will be unmounted unexpectedly this time,
-    // as we'll return proxy but we returned the original class the last time.
-    // https://github.com/gaearon/react-hot-loader/issues/241
-    if (!warnedAboutTypes[id]) {
-      warnedAboutTypes[id] = true;
-      console.error(
-        `React Hot Loader: ${source.localName} from ${source.fileName} will not ` +
-        `hot reload correctly because it contains an imperative call like ` +
-        `ReactDOM.render() in the same file. Split ${source.localName} into a ` +
-        `separate file for hot reloading to work.`
-      );
-    }
+  var id = idsByType.get(type);
+  if (!id) {
     return type;
   }
 
   // We use React Proxy to generate classes that behave almost
   // the same way as the original classes but are updatable with
   // new versions without destroying original instances.
-  if (!proxies[id]) {
-    proxies[id] = createProxy(type);
+  if (!proxiesByID[id]) {
+    proxiesByID[id] = createProxy(type);
   } else if (!type.hasOwnProperty('__hasBeenUsedForProxy')) {
-    proxies[id].update(type);
+    proxiesByID[id].update(type);
   }
-  // Don't update proxy with the same class.
-  // This makes sure stale old classes never revive.
-  // https://github.com/gaearon/react-hot-loader/issues/248
-  setFlag(type, '__hasBeenUsedForProxy');
 
   // Give proxy class to React instead of the real class.
-  return proxies[id].get();
+  return proxiesByID[id].get();
 }
 
 module.exports = resolveType;