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#[allow(unused_imports, clippy::wildcard_imports)]
use super::*;
/// TransactionMeta is a borrowing equivalent of [`TransactionMeta`](super::super::TransactionMeta)
/// over `'static` data, for const XDR encoding.
#[derive(Clone, Debug, Hash, PartialEq, Eq, PartialOrd, Ord)]
#[cfg_attr(feature = "arbitrary", derive(Arbitrary))]
#[allow(clippy::large_enum_variant)]
pub enum TransactionMeta {
V0(VecM<OperationMeta>),
V1(TransactionMetaV1),
V2(TransactionMetaV2),
V3(TransactionMetaV3),
V4(TransactionMetaV4),
}
impl TransactionMeta {
#[must_use]
pub const fn discriminant(&self) -> i32 {
#[allow(clippy::match_same_arms)]
match self {
Self::V0(_) => 0,
Self::V1(_) => 1,
Self::V2(_) => 2,
Self::V3(_) => 3,
Self::V4(_) => 4,
}
}
}
impl TransactionMeta {
/// The exact XDR-encoded length of this value, in bytes.
///
/// Evaluable in a const context, so a caller (such as a proc-macro) can
/// size a buffer for [`Self::const_to_xdr`] at compile time.
#[must_use]
pub const fn const_xdr_len(&self) -> usize {
let mut empty: [u8; 0] = [];
let mut w = ConstWriter::new(&mut empty);
w.write_type_transaction_meta(self);
w.len()
}
/// Serialize this value as XDR into a fixed-size `[u8; N]` using only const
/// operations. This is the const counterpart to
/// [`WriteXdr::to_xdr`](super::super::WriteXdr::to_xdr).
///
/// `N` must equal [`Self::const_xdr_len`]. It is intended for callers, such
/// as a proc-macro, that compute the length with `const_xdr_len` and pass
/// it as `N`; `const_to_xdr` itself does not need to call `const_xdr_len`.
///
/// # Panics
///
/// Panics if `N` does not equal the value's [`Self::const_xdr_len`].
#[must_use]
pub const fn const_to_xdr<const N: usize>(&self) -> [u8; N] {
let mut buf = [0u8; N];
let mut w = ConstWriter::new(&mut buf);
w.write_type_transaction_meta(self);
assert!(
w.len() == N,
"const_to_xdr: N does not equal the XDR-encoded length"
);
buf
}
}
impl ConstWriter<'_> {
/// Serializes a [`TransactionMeta`], mirroring `<TransactionMeta as WriteXdr>::write_xdr`.
pub const fn write_type_transaction_meta(&mut self, v: &TransactionMeta) {
let d = v.discriminant();
self.write_i32(d);
#[allow(clippy::match_same_arms)]
match v {
TransactionMeta::V0(value) => {
self.write_type_vec_operation_meta(value);
}
TransactionMeta::V1(value) => {
self.write_type_transaction_meta_v1(value);
}
TransactionMeta::V2(value) => {
self.write_type_transaction_meta_v2(value);
}
TransactionMeta::V3(value) => {
self.write_type_transaction_meta_v3(value);
}
TransactionMeta::V4(value) => {
self.write_type_transaction_meta_v4(value);
}
}
}
}