Relative links to asbolute regex

relative-to-absolute.js

const text = `
<p>This is some test with <a href=\"/piesync.html\">a relative link</a> and one with an <a href=\"http://piesync.com\">absolute link</a></p>
<p>This is some test with <a href=\"/piesync.html\" title="test">a relative link</a> and one with an <a href=\"http://www.piesync.com\">absolute link</a></p>
<p>This is some test with <a href=\"/piesync/hello/path\">a relative link</a> and one with an <a href=\"http://piesync.com\">absolute link</a></p>
<p>This is some test with <a href=\"/\">a relative link</a> and one with an <a href=\"http://piesync.com\">absolute link</a></p>
<p>This is some test with <a href=\"/?_ga=2.12323232.131232131.423413123-1231231.123123123\">a relative link</a> and one with an <a href=\"http://piesync.com\">absolute link</a></p>
`;

let replaced = text.replace(/<a href="(\/([\w.\/?=-]+)|\/)/gm, `<a href="https://www.domain.com$1`);

console.log(replaced);