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use crate::records::pending_type::PendingType;
use crate::records::pending_type_pack::PendingTypePack;
use crate::type_aliases::type_or_pack_id::TypeOrPackId;
use alloc::boxed::Box;
use alloc::vec::Vec;
use luaur_common::records::dense_hash_map::DenseHashMap;
#[derive(Debug)]
pub struct TxnLog {
pub(crate) type_var_changes:
DenseHashMap<*const crate::records::r#type::Type, Box<PendingType>>,
pub(crate) type_pack_changes:
DenseHashMap<*const crate::records::type_pack_var::TypePackVar, Box<PendingTypePack>>,
pub(crate) parent: *mut TxnLog,
pub(crate) owned_seen: Vec<(TypeOrPackId, TypeOrPackId)>,
/// The active "seen pairs" set. Points either at this log's own storage
/// (`owned_seen_box`, below) or — for a child/derived log — at a parent's.
pub(crate) shared_seen: *mut Vec<(TypeOrPackId, TypeOrPackId)>,
/// Heap storage for `shared_seen` when THIS log owns it. C++ uses a member
/// `std::vector` whose destructor frees it; the Rust port originally did
/// `Box::into_raw(Box::new(Vec::new()))` and never freed it — a leak of one
/// Vec per top-level unification (caught by the fuzz suite's LeakSanitizer in
/// `mk_unifier`). A boxed Vec gives a stable address that survives the log
/// being moved/returned, and being owned here it is freed on drop. `None`
/// when this log borrows a parent's set (`shared_seen` then aliases it).
pub(crate) owned_seen_box: Option<Box<Vec<(TypeOrPackId, TypeOrPackId)>>>,
pub(crate) radioactive: bool,
}
impl Clone for TxnLog {
fn clone(&self) -> Self {
// Deep-copy the owned seen storage so the clone owns (and later frees) its
// own box, with `shared_seen` re-pointed into it. A borrowing log (no box)
// clones the borrowed pointer as-is. The previous `#[derive(Clone)]` copied
// `shared_seen` as a raw pointer into the *original's* box — fine for the
// overload-resolution clones that only read changes, but it must not be the
// owner, or the box would be double-freed / aliased.
match &self.owned_seen_box {
Some(b) => {
let mut nb = b.clone();
let sp: *mut Vec<(TypeOrPackId, TypeOrPackId)> = nb.as_mut();
TxnLog {
type_var_changes: self.type_var_changes.clone(),
type_pack_changes: self.type_pack_changes.clone(),
parent: self.parent,
owned_seen: self.owned_seen.clone(),
shared_seen: sp,
owned_seen_box: Some(nb),
radioactive: self.radioactive,
}
}
None => TxnLog {
type_var_changes: self.type_var_changes.clone(),
type_pack_changes: self.type_pack_changes.clone(),
parent: self.parent,
owned_seen: self.owned_seen.clone(),
shared_seen: self.shared_seen,
owned_seen_box: None,
radioactive: self.radioactive,
},
}
}
}