cpoptions in Vim is so complicated...

{'{,''}’} this pattern will cause a wrong % action (MATCHING PARENTHESES SEARCH) in Vim with default cpoptions flag.

A real Example in JavaScript

if (~item.indexOf('\n ')) {  
    space -= item.length;  
    item = !this.options.pedantic  
      ? item.replace(new RegExp('^ {1,' + space + '}', 'gm'), '')  
      : item.replace(/^ {1,4}/gm, '');  
}  

And if we :set cpoptions&vi to change cpoptions let Vim act like VI, the result seems correct.

But after read the doc in Vim, proved it was a coincidence because VI just treat this pattern a PLAINTEXT without considering parens in “” or ''. So, if you remove one of the parens, the result get wrong again.

What I am curious about is that the default syntax highlighting is correct but the % action is wrong in Vim with such pattern.

I know install a plugin like matchit can probably resolve this problem. But is there any built-in method to deal with it?

My friend found this problem while he was trying to fold his code and got an unpredictable result.

References

• Vim finds incorrect matching bracket when using %