bitcoinjs-lib/ts_src/templates/pubkey/input.ts

// {signature}

import { Stack } from '../../payments';
import * as bscript from '../../script';

export function check(script: Buffer | Stack): boolean {
  const chunks = bscript.decompile(script) as Stack;

  return (
    chunks.length === 1 &&
    bscript.isCanonicalScriptSignature(chunks[0] as Buffer)
  );
}
check.toJSON = () => {
  return 'pubKey input';
};