rndebugger-open: Remove --expo flag

expo 49 start using 8081 as default packager port, also packager-info is no longer supported.

users are also able to use `--port 19000` for Expo <= 48.

closes #689

npm-package/README.md

@@ -47,6 +47,8 @@ $ REACT_DEBUGGER="rndebugger-open --open --port 8081" npm start
 $ set REACT_DEBUGGER="rndebugger-open --open --port 8081" && npm start
 ```
 
+If you're using Expo <= 48, use port 19000 instead of 8081.
+
 #### Options (--option)
 
 Name                  | Description
@@ -55,7 +57,6 @@ Name                  | Description
 `revert`              | Revert rndebugger-open injection. Default is `false`
 `open`                | Run open directly instead of inject patch
 `port`                | Specified react-native packager port with `--open` option. Default is `8081`
-`expo`                | Use [Expo](https://github.com/expo)'s RN packager port if you're not specified port.
 
 You can also [`Launch by CLI or React Native packager`](https://github.com/jhen0409/react-native-debugger/blob/master/docs/getting-started.md#launch-by-cli-or-react-native-packager-macos-only) instead of this package.
 

npm-package/bin/rndebugger-open.js

@@ -2,19 +2,7 @@
 
 'use strict';
 
-const fs = require('fs');
-const path = require('path');
-
 const defaultPort = 8081;
-const expoDefaultPort = 19000;
-
-const expoInfoPath = path.join(process.cwd(), '.expo/packager-info.json');
-
-/* eslint-disable global-require */
-const getExpoPort = () =>
-  (fs.existsSync(expoInfoPath)
-    ? require(expoInfoPath).packagerPort || expoDefaultPort
-    : expoDefaultPort);
 
 const argv = require('minimist')(process.argv.slice(2), {
   boolean: [
@@ -26,8 +14,6 @@ const argv = require('minimist')(process.argv.slice(2), {
     'macos',
     // Open directly instead of Inject code
     'open',
-    // Use expo packager port (getExpoPort) instead of RN packager default port (8081)
-    'expo',
   ],
   string: ['port', 'host'],
   default: {
@@ -36,7 +22,7 @@ const argv = require('minimist')(process.argv.slice(2), {
 });
 
 let moduleName;
-argv.port = Number(argv.port) || (argv.expo ? getExpoPort() : defaultPort);
+argv.port = Number(argv.port) || defaultPort;
 if (argv.open && (argv.port || argv.host)) {
   moduleName = '../lib/open';
 } else {