Class ScriptMaker

src/script/descriptor.cpp:1594–1626

* The context for converting a Miniscript descriptor into a Script. */

 * The context for converting a Miniscript descriptor into a Script.
 */
class ScriptMaker {
    //! Keys contained in the Miniscript (the evaluation of DescriptorImpl::m_pubkey_args).
    const std::vector<CPubKey>& m_keys;
    //! The script context we're operating within (Tapscript or P2WSH).
    const miniscript::MiniscriptContext m_script_ctx;

    //! Get the ripemd160(sha256()) hash of this key.
    //! Any key that is valid in a descriptor serializes as 32 bytes within a Tapscript context. So we
    //! must not hash the sign-bit byte in this case.
    uint160 GetHash160(uint32_t key) const {
        if (miniscript::IsTapscript(m_script_ctx)) {
            return Hash160(XOnlyPubKey{m_keys[key]});
        }
        return m_keys[key].GetID();
    }

public:
    ScriptMaker(const std::vector<CPubKey>& keys LIFETIMEBOUND, const miniscript::MiniscriptContext script_ctx) : m_keys(keys), m_script_ctx{script_ctx} {}

    std::vector<unsigned char> ToPKBytes(uint32_t key) const {
        // In Tapscript keys always serialize as x-only, whether an x-only key was used in the descriptor or not.
        if (!miniscript::IsTapscript(m_script_ctx)) {
            return {m_keys[key].begin(), m_keys[key].end()};
        }
        const XOnlyPubKey xonly_pubkey{m_keys[key]};
        return {xonly_pubkey.begin(), xonly_pubkey.end()};
    }

    std::vector<unsigned char> ToPKHBytes(uint32_t key) const {
        auto id = GetHash160(key);
        return {id.begin(), id.end()};
    }
};

/**
 * The context for converting a Miniscript descriptor to its textual form.