How to resolve the error on 'react-native start'

Solution 1:

I just got a similar error for the first time today. It appears in \node_modules\metro-config\src\defaults\blacklist.js, there is an invalid regular expression that needed changed. I changed the first expression under sharedBlacklist from:

var sharedBlacklist = [
  /node_modules[/\\]react[/\\]dist[/\\].*/,
  /website\/node_modules\/.*/,
  /heapCapture\/bundle\.js/,
  /.*\/__tests__\/.*/
];

to:

var sharedBlacklist = [
  /node_modules[\/\\]react[\/\\]dist[\/\\].*/,
  /website\/node_modules\/.*/,
  /heapCapture\/bundle\.js/,
  /.*\/__tests__\/.*/
];

Solution 2:

This is caused by node v12.11.0 due to the way it deals regular location there two ways to solve this problem

Method I

You can downgrade to node v12.10.0 this will apply the correct way to deal with parsing error

Method II

You can correctly terminate the regular expression in you case by changing the file located a:

\node_modules\metro-config\src\defaults\blacklist.js

From:

var sharedBlacklist = [
  /node_modules[/\\]react[/\\]dist[/\\].*/,
  /website\/node_modules\/.*/,
  /heapCapture\/bundle\.js/,
  /.*\/__tests__\/.*/
];

To:

 var sharedBlacklist = [
  /node_modules[\/\\]react[\/\\]dist[\/\\].*/,
  /website\/node_modules\/.*/,
  /heapCapture\/bundle\.js/,
  /.*\/__tests__\/.*/
];

Solution 3:

It is due to mismatched blacklist file configuration.

To resolve that,

1. We have to move to the project folder.

2. Open \node_modules\metro-config\src\defaults\blacklist.js

3. Replace the following.

From

var sharedBlacklist = [
  /node_modules[/\\]react[/\\]dist[/\\].*/,
  /website\/node_modules\/.*/,
  /heapCapture\/bundle\.js/,
  /.*\/__tests__\/.*/
];

To

var sharedBlacklist = [
  /node_modules[\/\\]react[\/\\]dist[\/\\].*/,
  /website\/node_modules\/.*/,
  /heapCapture\/bundle\.js/,
  /.*\/__tests__\/.*/
];