Merge branch 'dev' into minzo-readme-19.0

Author: MarkTeets

.babelrc

@@ -1,6 +1,4 @@
 {
-  "presets": [
-    "airbnb"
-  ],
+  "presets": ["airbnb", "@babel/preset-typescript"],
   "plugins": ["@emotion"]
 }

.eslintrc

@@ -3,10 +3,12 @@
     "airbnb",
     "plugin:jest/recommended",
     "plugin:@typescript-eslint/eslint-recommended",
-    "plugin:@typescript-eslint/recommended"
+    "plugin:@typescript-eslint/recommended",
+    "plugin:testing-library/react", // added in for RTL tests
+    "plugin:jest-dom/recommended" // added in for RTL tests
   ],
   "root": true,
-  "plugins": ["jest", "react", "react-hooks", "@typescript-eslint"],
+  "plugins": ["jest", "react", "react-hooks", "@typescript-eslint", "testing-library", "jest-dom"],
   "rules": {
     "arrow-parens": [2, "as-needed"],
     "import/no-unresolved": "off",

demo-app/package.json

@@ -31,6 +31,7 @@
     "react": "^18.1.0",
     "react-dom": "^18.1.0",
     "react-router-dom": "^6.3.0",
-    "ts-node": "^10.4.0"
+    "ts-node": "^10.4.0",
+    "use-immer": "^0.9.0"
   }
 }

demo-app/src/client/Components/Buttons.tsx

@@ -1,7 +1,7 @@
 import React from 'react';
 import Increment from './Increment';
 
-function Buttons():JSX.Element {
+function Buttons(): JSX.Element {
   const buttons = [];
   for (let i = 0; i < 4; i++) {
     buttons.push(<Increment key={i} />);
@@ -20,4 +20,3 @@ function Buttons():JSX.Element {
 }
 
 export default Buttons;
-

demo-app/src/client/Components/ButtonsWithMoreHooks.jsx

@@ -0,0 +1,61 @@
+import React, {useState, createContext} from 'react';
+import IncrementWithMoreHooks from './IncrementWithMoreHooks';
+
+/**
+ * This component as well as IncrementWithMoreHooks were made to show where data for different 
+ * hooks show up in the react fiber tree.
+ */
+
+/** 
+ * This file is a JSX file, not a TSX file, on purpose. The code won't be converted to common JS
+ * before being bundled by webpack. There were some errors that weren't showing up for the other 
+ * Increment.tsx file based on how webpack uglifies ES6 files. Maintaining this as a JSX file
+ * will help check for these types of issues.
+ */
+
+/**
+ * How Reactime extracts useState data and what would have to be done 
+ * to extract useContext and useReducer data:
+ * 
+ * When extracting a functional component's useState data from the fiber tree in the backend of 
+ * Reactime, said data is stored on said component's fiber tree node at its memoizedState property, 
+ * which is a linked list with each node holding data for each useState invocation (some but 
+ * not all other hooks also store nodes with data here). Each useState memoizedState node includes
+ * the variable (e.g. user) and its corresponding dispatch function (e.g. setUser). This dispatch
+ * function is required to use Reactime's timeJump feature.
+ * 
+ * useContext data is stored on the property "dependencies", and only the data passed into the
+ * value attritibute of the 'context'.Provider element will be there. For tripContext.Provider,
+ * we pass down "trip" without "setTrip", so we won't have access to the 'trip' dispatch function 
+ * in the "IncrementWithMoreHooks" component, meaning Reactime's timeJump won't work without 
+ * finding the 'trip' dispatch function by coming into this component where useState was invoked and
+ * storing it in the appropriate place. This is easy enough for useState variables, but useContext 
+ * is commonly used with useReducer which is an entirely different beast. 
+ * 
+ * I advise solving the puzzle of making useReducer work with the timeJump functionality before 
+ * integrating other hooks. Look at time jumping in the Redux dev tools chrome extension for 
+ * inspiration, because you essentially need to recreate that within Reactime. 
+ */
+
+// userInCreateContext is different from 'user' to see where this variable name showed up in the AST
+export const userContext = createContext({ userInCreateContext: 'null', setUser: undefined });
+export const tripContext = createContext({ trip: 'null', setTrip: undefined });
+
+const ButtonsWithMoreHooks = () => {
+  const [user, setUser] = useState('null');
+  const userValue = { user, setUser };
+  const [trip, setTrip ] = useState('Hawaii');
+  const tripValue = { trip };
+
+  return (
+    <div className='buttons' key='increment container'>
+      <userContext.Provider value={userValue} key="userContext Provider">
+        <tripContext.Provider value={tripValue} key="tripContext Provider">
+          <IncrementWithMoreHooks key={'IncrementWithMoreHooks'} />
+        </tripContext.Provider>
+      </userContext.Provider>
+    </div>
+  );
+}
+
+export default ButtonsWithMoreHooks;