Change REACT_APP prefix to CY_APP to align with our standards

Author: SpaceK33z

packages/react-cy-scripts/config/env.js

@@ -9,15 +9,15 @@
  */
 // @remove-on-eject-end
 
-// Grab NODE_ENV and REACT_APP_* environment variables and prepare them to be
+// Grab NODE_ENV and CY_APP_* environment variables and prepare them to be
 // injected into the application via DefinePlugin in Webpack configuration.
 
-var REACT_APP = /^REACT_APP_/i;
+var CY_APP = /^CY_APP_/i;
 
 function getClientEnvironment(publicUrl) {
   var raw = Object
     .keys(process.env)
-    .filter(key => REACT_APP.test(key))
+    .filter(key => CY_APP.test(key))
     .reduce((env, key) => {
       env[key] = process.env[key];
       return env;

packages/react-cy-scripts/fixtures/kitchensink/.env

@@ -1 +1 @@
-REACT_APP_FILE_ENV_MESSAGE=fromtheenvfile
+CY_APP_FILE_ENV_MESSAGE=fromtheenvfile

packages/react-cy-scripts/fixtures/kitchensink/src/features/env/FileEnvVariables.js

@@ -1,5 +1,5 @@
 import React from 'react'
 
 export default () => (
-  <span id="feature-file-env-variables">{process.env.REACT_APP_FILE_ENV_MESSAGE}.</span>
+  <span id="feature-file-env-variables">{process.env.CY_APP_FILE_ENV_MESSAGE}.</span>
 )

packages/react-cy-scripts/fixtures/kitchensink/src/features/env/ShellEnvVariables.js

@@ -1,5 +1,5 @@
 import React from 'react'
 
 export default () => (
-  <span id="feature-shell-env-variables">{process.env.REACT_APP_SHELL_ENV_MESSAGE}.</span>
+  <span id="feature-shell-env-variables">{process.env.CY_APP_SHELL_ENV_MESSAGE}.</span>
 )

packages/react-cy-scripts/template/README.md

@@ -442,14 +442,14 @@ Alternatively, you can force the linter to ignore any line by adding `// eslint-
 
 Your project can consume variables declared in your environment as if they were declared locally in your JS files. By
 default you will have `NODE_ENV` defined for you, and any other environment variables starting with
-`REACT_APP_`.
+`CY_APP_`.
 
 **The environment variables are embedded during the build time**. Since Create React App produces a static HTML/CSS/JS bundle, it can’t possibly read them at runtime. To read them at runtime, you would need to load HTML into memory on the server and replace placeholders in runtime, just like [described here](#injecting-data-from-the-server-into-the-page). Alternatively you can rebuild the app on the server anytime you change them.
 
->Note: You must create custom environment variables beginning with `REACT_APP_`. Any other variables except `NODE_ENV` will be ignored to avoid accidentally [exposing a private key on the machine that could have the same name](https://github.com/facebookincubator/create-react-app/issues/865#issuecomment-252199527). Changing any environment variables will require you to restart the development server if it is running.
+>Note: You must create custom environment variables beginning with `CY_APP_`. Any other variables except `NODE_ENV` will be ignored to avoid accidentally [exposing a private key on the machine that could have the same name](https://github.com/facebookincubator/create-react-app/issues/865#issuecomment-252199527). Changing any environment variables will require you to restart the development server if it is running.
 
 These environment variables will be defined for you on `process.env`. For example, having an environment
-variable named `REACT_APP_SECRET_CODE` will be exposed in your JS as `process.env.REACT_APP_SECRET_CODE`.
+variable named `CY_APP_SECRET_CODE` will be exposed in your JS as `process.env.CY_APP_SECRET_CODE`.
 
 There is also a special built-in environment variable called `NODE_ENV`. You can read it from `process.env.NODE_ENV`. When you run `npm start`, it is always equal to `'development'`, when you run `npm test` it is always equal to `'test'`, and when you run `npm run build` to make a production bundle, it is always equal to `'production'`. **You cannot override `NODE_ENV` manually.** This prevents developers from accidentally deploying a slow development build to production.
 
@@ -465,14 +465,14 @@ render() {
     <div>
       <small>You are running this application in <b>{process.env.NODE_ENV}</b> mode.</small>
       <form>
-        <input type="hidden" defaultValue={process.env.REACT_APP_SECRET_CODE} />
+        <input type="hidden" defaultValue={process.env.CY_APP_SECRET_CODE} />
       </form>
     </div>
   );
 }
 ```
 
-During the build, `process.env.REACT_APP_SECRET_CODE` will be replaced with the current value of the `REACT_APP_SECRET_CODE` environment variable. Remember that the `NODE_ENV` variable will be set for you automatically.
+During the build, `process.env.CY_APP_SECRET_CODE` will be replaced with the current value of the `CY_APP_SECRET_CODE` environment variable. Remember that the `NODE_ENV` variable will be set for you automatically.
 
 When you load the app in the browser and inspect the `<input>`, you will see its value set to `abcdef`, and the bold text will show the environment provided when using `npm start`:
 
@@ -485,7 +485,7 @@ When you load the app in the browser and inspect the `<input>`, you will see its
 </div>
 ```
 
-The above form is looking for a variable called `REACT_APP_SECRET_CODE` from the environment. In order to consume this
+The above form is looking for a variable called `CY_APP_SECRET_CODE` from the environment. In order to consume this
 value, we need to have it defined in the environment. This can be done using two ways: either in your shell or in
 a `.env` file. Both of these ways are described in the next few sections.
 
@@ -501,15 +501,15 @@ When you compile the app with `npm run build`, the minification step will strip
 
 ### Referencing Environment Variables in the HTML
 
-You can also access the environment variables starting with `REACT_APP_` in the `public/index.html`. For example:
+You can also access the environment variables starting with `CY_APP_` in the `public/index.html`. For example:
 
 ```html
-<title>%REACT_APP_WEBSITE_NAME%</title>
+<title>%CY_APP_WEBSITE_NAME%</title>
 ```
 
 Note that the caveats from the above section apply:
 
-* Apart from a few built-in variables (`NODE_ENV` and `PUBLIC_URL`), variable names must start with `REACT_APP_` to work.
+* Apart from a few built-in variables (`NODE_ENV` and `PUBLIC_URL`), variable names must start with `CY_APP_` to work.
 * The environment variables are injected at build time. If you need to inject them at runtime, [follow this approach instead](#generating-dynamic-meta-tags-on-the-server).
 
 ### Adding Temporary Environment Variables In Your Shell
@@ -520,15 +520,15 @@ life of the shell session.
 #### Windows (cmd.exe)
 
 ```cmd
-set REACT_APP_SECRET_CODE=abcdef&&npm start
+set CY_APP_SECRET_CODE=abcdef&&npm start
 ```
 
 (Note: the lack of whitespace is intentional.)
 
 #### Linux, macOS (Bash)
 
 ```bash
-REACT_APP_SECRET_CODE=abcdef npm start
+CY_APP_SECRET_CODE=abcdef npm start
 ```
 
 ### Adding Development Environment Variables In `.env`
@@ -537,7 +537,7 @@ REACT_APP_SECRET_CODE=abcdef npm start
 To define permanent environment variables, create a file called `.env` in the root of your project:
 
 ```
-REACT_APP_SECRET_CODE=abcdef
+CY_APP_SECRET_CODE=abcdef
 ```
 
 These variables will act as the defaults if the machine does not explicitly set them.<br>