Backslashes in output from yarn fail when they match standard escape sequences in Windows

[zhulika]

The error reporting seems to have an escaping issue with folder names that start with 'n' on Windows. For example, when printing an error from the yarn start command, it outputs the directory :

Directory: C:\root\name

as:

Directory: C:\\root\\
ame

This is on Windows 10 and with yarn v1.5.1

[BYK]

Relevant code:

yarn/src/reporters/base-reporter.js

Lines 46 to 49 in a35a4f9

	// should match all literal line breaks and
	// "u001b" that follow an odd number of backslashes and convert them to ESC
	// we do this because the JSON.stringify process has escaped these characters
	return str.replace(/((?:^|[^\\])(?:\\{2})*)\\u001[bB]/g, '$1\u001b').replace(/[\\]r[\\]n|[\\]n/g, os.EOL);