Add functionality to replace null in props with undefined

Author: MaySoMusician

react_ujs/index.js

@@ -8,6 +8,7 @@ var constructorFromRequireContext = require("./src/getConstructor/fromRequireCon
 var constructorFromRequireContextWithGlobalFallback = require("./src/getConstructor/fromRequireContextWithGlobalFallback")
 var constructorFromRequireContextsWithGlobalFallback = require("./src/getConstructor/fromRequireContextsWithGlobalFallback")
 const { supportsHydration, reactHydrate, createReactRootLike } = require("./src/renderHelpers")
+const { replaceNullWithUndefined } = require("./src/options")
 
 var ReactRailsUJS = {
   // This attribute holds the name of component which should be mounted
@@ -31,6 +32,11 @@ var ReactRailsUJS = {
 
   components: {},
 
+  // Set default values for options.
+  options: {
+    replaceNull: false,
+  },
+
   // helper method for the mount and unmount methods to find the
   // `data-react-class` DOM elements
   findDOMNodes: function(searchSelector) {
@@ -106,7 +112,8 @@ var ReactRailsUJS = {
       var className = node.getAttribute(ujs.CLASS_NAME_ATTR);
       var constructor = ujs.getConstructor(className);
       var propsJson = node.getAttribute(ujs.PROPS_ATTR);
-      var props = propsJson && JSON.parse(propsJson);
+      var props = propsJson && (ujs.options.replaceNull ? replaceNullWithUndefined(JSON.parse(propsJson))
+                                                        : JSON.parse(propsJson));
       var hydrate = node.getAttribute(ujs.RENDER_ATTR);
       var cacheId = node.getAttribute(ujs.CACHE_ID_ATTR);
       var turbolinksPermanent = node.hasAttribute(ujs.TURBOLINKS_PERMANENT_ATTR);

react_ujs/src/options.js

@@ -0,0 +1,13 @@
+export function replaceNullWithUndefined(obj) {
+  Object.entries(obj).forEach((entry) => {
+    const key = entry[0]
+    const value = entry[1]
+    if(!!value && typeof value === 'object') {
+      return replaceNullWithUndefined(value)
+    }
+    if (value === null) {
+      obj[key] = undefined
+    }
+  })
+  return obj
+}