regex-occurrence 
Get the number of occurrences of a RegExp in a string
Install
$ npm install --save regex-occurrence
Usage
const regexOccurrence = require('regex-occurrence');
regexOccurrence('foo bar', /F/);
//=> 0
regexOccurrence('foo bar', /Foo/i);
//=> 1
regexOccurrence('foo bar\nfoo baz', [/foo/, /baz/]);
//=> 2
regexOccurrence('foo bar\nfoo baz', [/foo/g, /baz/]);
//=> 3
API
Type: string
The string to search in.
search
Type: RegExp, RegExp[]
The regular expressions to search for.
License
MIT © Sam Verschueren