Broken regular expression in Windows exclusionList.js path separator replacement

Do you want to request a feature or report a bug?

Bug

What is the current behavior?

On Windows, I get an error when running react-native start:

Invalid regular expression: /(.*\\__fixtures__\\.*|node_modules[\\\]react[\\\]dist[\\\].*|website\\node_modules\\.*|heapCapture\\bundle\.js|.*\\__tests__\\.*)$/: Unterminated character class. Run CLI with --verbose flag for more details.
SyntaxError: Invalid regular expression: /(.*\\__fixtures__\\.*|node_modules[\\\]react[\\\]dist[\\\].*|website\\node_modules\\.*|heapCapture\\bundle\.js|.*\\__tests__\\.*)$/: Unterminated character class

The Fix

 function escapeRegExp(pattern) {
   if (Object.prototype.toString.call(pattern) === '[object RegExp]') {
-    return pattern.source.replace(/\//g, path.sep);
+    return pattern.source.replace(/\//g, '\\' + path.sep);
   } else if (typeof pattern === 'string') {
     var escaped = pattern.replace(/[\-\[\]\{\}\(\)\*\+\?\.\\\^\$\|]/g, '\\$&');
     // convert the '/' into an escaped local file separator
     return escaped.replace(/\//g, '\\' + path.sep);
#-----------------------------------^ The replace method above should also escape `path.sep`

If you look at line 22 of exclusionList.js you’ll see it replaces / with "\\" + path.sep but on line 18 it replaces the source with only path.sep. Instead it should also replace it with "\\" + path.sep.

[Slapbox]

@saurabhbh21 the Regex in the node_modules files is not relevant to this issue unless they’re being loaded directly into your Metro configuration, like in the blacklist/blocklist. I think you’re facing some other problem.

[cpojer]

Can you send a PR?