Method isScripthashInput

lib/script/script.js:2342–2384

* "Guess" whether the input script is pay-to-scripthash. * This method is not 100% reliable. * @returns {Boolean}

()

   */

  isScripthashInput() {
    if (this.code.length < 1)
      return false;

    // Grab the raw redeem script.
    const raw = this.getData(-1);

    // Last data element should be an array
    // for the redeem script.
    if (!raw)
      return false;

    // Testing for scripthash inputs requires
    // some evil magic to work. We do it by
    // ruling things _out_. This test will not
    // be correct 100% of the time. We rule
    // out that the last data element is: a
    // null dummy, a valid signature, a valid
    // key, and we ensure that it is at least
    // a script that does not use undefined
    // opcodes.
    if (raw.length === 0)
      return false;

    if (common.isSignatureEncoding(raw))
      return false;

    if (common.isKeyEncoding(raw))
      return false;

    const redeem = Script.fromRaw(raw);

    if (!redeem.isCode())
      return false;

    if (redeem.isUnspendable())
      return false;

    if (!this.isPushOnly())
      return false;

    return true;
  }

  /**
   * Get P2SH redeem script if present.