JS weirdness

Output

%00.com
%00.com
exec 7 %00.com %00.com 7 %00.com
exec3

Output2

%00.com
<NULL>.com
exec 7 %00.com 
exec2

Source.js

console.log(input);
  let domain = decodeURIComponent(input);
  console.log(decodeURIComponent(input));
  console.log("exec", input.length, input, decodeURIComponent(input), domain.length, domain);
  if (domain.search(/\u0000|\u0009|\u000A|\u000D|\u0020|#|%|\/|:|\?|@|\[|\\|\]/) !== -1) {
    console.log("exec2");
    throw new TypeError("Invalid Host");
  }
  console.log("exec3");