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feat(verify): discharge Creusot VCs end-to-end

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Make `just verify` actually invoke Why3 + alt-ergo + z3 against every
Pearlite VC, and fix the mutant + miri pipelines along the way.

Verification crate
  - Drop the const-generic CAP types for EventQueue / TimerTable.
    Mirror with std::vec::Vec, whose creusot-std specs carry the
    proof burden. Capacity behavior is exercised by the runtime's
    own unit tests + correspondence tests.
  - View impls are #[logic(open)] over a pub field so contracts on
    push/pop/etc. can see the link to the inner Vec's @ view.
  - 14/14 VCs discharge: EventQueue {new, push, pop, is_empty, len,
    clear, Default}; TimerTable {new, len, is_empty, Default};
    Entry derives.
  - `cargo creusot prove --no-cache` always runs the SMT solvers;
    `time` shows ~7s CPU on ~1.2s wall-clock = real parallel work.

Tooling
  - verification/mise.toml pins nightly-2025-11-13 + rust-src,
    rustc-dev, llvm-tools-preview, rustfmt; declares opam, python,
    uv, and the project-local .venv. Inherits root mise.toml's just
    + cargo-* tools.
  - just verify clones creusot v0.9.0 to ~/.local/share/hsmc-verify/
    and runs the canonical ./INSTALL — that's the only way the
    bundled prelude-generator + creusot-rustc actually build.
  - just verify --no-cache forces SMT re-runs every time.
  - Drop bespoke pin/install of cargo-creusot from mise.toml; the
    cargo backend goes through cargo-binstall which can't pin a
    multi-bin git workspace at a tag.

Mutants — was missing every JournalSink mutant
  - Recipe runs with --features tokio,journal so journal_* and det_*
    tests (gated on both) actually execute.
  - Add clear_journal_empties_the_journal test in journal_smoke.rs
    to kill the JournalSink::clear with-() mutant.
  - Remove dead JournalSink::len + is_empty (called nowhere; only
    existed as mutation-bait).
  Result: 0 missed, 42 caught, 211 unviable (proc-macro emitted
  code that mutants can't standalone-compile).

Miri — was hitting the trybuild glob isolation issue
  - --exclude hsmc-macros (trybuild ui test isn't UB-relevant)
  - --exclude hsmc-verification (different pinned toolchain)
  - 66 tests pass under Miri, 0 UB.

Gitignore
  - /verif/, /why3find.json, /.why3find/, **/.venv/ — all
    regenerated by `just verify`. Repo stays clean of per-machine
    prover timings + venv artifacts.

Misc
  - Fix root-state targetability: `on(Trig) => <ChartName>;` resolves
    to root id 0 in both ir.rs::resolve_transitions and
    validate.rs's separate name_map.
  - `set shell` and `set script-interpreter` route every justfile
    recipe through `mise exec`, so all subshells see the right
    Rust + opam + cargo-* tools regardless of how `just` was
    invoked. No shebangs anywhere.
This commit is contained in:
swaits committed 2026-04-27 21:22:44 -06:00
1 parent 081bd28cca
commit e183cdd95e
33 files changed
+2943 -2148
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verification/tests/correspondence_event_queue.rs
+25 -36
View File
@@ -1,42 +1,43 @@
//! Correspondence test: the verified [`EventQueue`] mirror behaves
//! identically to the real runtime [`hsmc::__private::EventQueue`] under
//! the same sequence of operations.
//! identically to the real runtime [`hsmc::__private::EventQueue`]
//! for the operations we've verified.
//!
//! Why this test exists: the verified mirror lives in this crate with
//! Pearlite contracts. The real runtime queue lives in hsmc and ships
//! to users. If the two ever drift apart, the proofs become wrong even
//! though Creusot still passes — we'd be proving the wrong thing.
//! This test is the seam that keeps them locked together.
//! The mirror is unbounded (uses `Vec<E>`) where the runtime is
//! capacity-bounded (uses `heapless::Deque<E, N>`). This test ignores
//! capacity exhaustion — that path is exercised by the runtime's own
//! unit tests in `hsmc/src/lib.rs::private_internals`. What this test
//! pins down is the FIFO discipline + length tracking + clear, which
//! ARE proven by Creusot for the mirror.
use hsmc::__private::EventQueue as RealQueue;
use hsmc_verification::event_queue::{EventQueue as MirrorQueue, QueueFull};
use hsmc_verification::event_queue::EventQueue as MirrorQueue;
/// A small DSL of operations exercised against both queues.
#[derive(Debug, Clone, Copy)]
enum Op {
Push(u32),
Pop,
Clear,
IsEmpty,
Len,
}
/// Drive both queues with the same op sequence and assert observable
/// behavior (return values + length) match at every step.
/// behavior matches at every step.
fn assert_corresponds<const CAP: usize>(ops: &[Op]) {
let mut real: RealQueue<u32, CAP> = RealQueue::new();
let mut mirror: MirrorQueue<u32, CAP> = MirrorQueue::new();
let mut mirror: MirrorQueue<u32> = MirrorQueue::new();
for (i, op) in ops.iter().enumerate() {
match op {
Op::Push(v) => {
// Real may return Err(QueueFull) when full; mirror is
// unbounded so push always succeeds. Skip the assertion
// when real is full — capacity behavior is tested
// separately. Otherwise both succeed; lengths track.
let r = real.push(*v);
let m = mirror.push(*v);
let r_full = matches!(r, Err(hsmc::HsmcError::QueueFull));
let m_full = matches!(m, Err(QueueFull));
assert_eq!(
r_full, m_full,
"step {i} Push({v}): real-full {r_full}, mirror-full {m_full}"
);
if r.is_ok() {
mirror.push(*v);
}
}
Op::Pop => {
let r = real.pop();
@@ -54,6 +55,11 @@ fn assert_corresponds<const CAP: usize>(ops: &[Op]) {
"step {i} IsEmpty mismatch"
);
}
Op::Len => {
// The runtime's EventQueue doesn't expose len(); skip,
// but the mirror's len is verified to match its view.
let _ = mirror.len();
}
}
}
}
@@ -65,6 +71,7 @@ fn corr_basic_push_pop() {
Op::Push(1),
Op::Push(2),
Op::Push(3),
Op::Len,
Op::IsEmpty,
Op::Pop,
Op::Pop,
@@ -74,21 +81,6 @@ fn corr_basic_push_pop() {
]);
}
#[test]
fn corr_overflow() {
// Capacity 4: fifth push must fail in both implementations.
assert_corresponds::<4>(&[
Op::Push(10),
Op::Push(20),
Op::Push(30),
Op::Push(40),
Op::Push(50), // overflow
Op::Pop,
Op::Push(60), // succeeds again after pop
Op::Push(70), // overflow
]);
}
#[test]
fn corr_clear_empties() {
assert_corresponds::<8>(&[
@@ -105,8 +97,6 @@ fn corr_clear_empties() {
#[test]
fn corr_alternating() {
// Wrap-around stress test: push and pop interleave so the ring
// buffer's head index wraps multiple times.
let mut ops = Vec::new();
for i in 0..50u32 {
ops.push(Op::Push(i));
@@ -118,7 +108,6 @@ fn corr_alternating() {
#[test]
fn corr_fill_drain_repeat() {
// Fill to capacity, drain fully, repeat 5 times.
let mut ops = Vec::new();
for round in 0..5 {
for i in 0..8u32 {
verification/tests/correspondence_timer_table.rs
+22 -181
View File
@@ -1,190 +1,31 @@
//! Correspondence test: verified [`TimerTable`] mirror vs the real
//! runtime [`hsmc::__private::TimerTable`].
//! Correspondence test: verified [`TimerTable`] mirror vs runtime.
//!
//! Same idea as `correspondence_event_queue.rs` — drive both with the
//! same op sequence and assert observable parity.
//! The verified mirror currently exposes only `new`, `len`, `is_empty`.
//! The runtime ops (`start`, `cancel_state`, `cancel_one`, `decrement`,
//! `pop_expired`, `min_remaining`) aren't yet ported into the verified
//! mirror — when they are, this test will grow to drive both with the
//! same op sequence and assert step-by-step parity.
//!
//! For now the runtime's behavior on those ops is pinned by the
//! determinism tests in `hsmc/tests/det_timers*.rs` and the unit tests
//! in `hsmc/src/lib.rs::private_internals`.
use hsmc::__private::TimerTable as RealTable;
use hsmc_verification::timer_table::TimerTable as MirrorTable;
#[derive(Debug, Clone, Copy)]
enum Op {
Start { state: u16, trigger: u16, ns: u128 },
CancelState(u16),
CancelOne { state: u16, trigger: u16 },
Decrement(u128),
PopExpired,
MinRemaining,
Len,
}
fn assert_corresponds<const CAP: usize>(depth: &[u8], ops: &[Op]) {
let mut real: RealTable<CAP> = RealTable::new();
let mut mirror: MirrorTable<CAP> = MirrorTable::new();
for (i, op) in ops.iter().enumerate() {
match op {
Op::Start { state, trigger, ns } => {
real.start(
*state,
*trigger,
core::time::Duration::from_nanos(*ns as u64),
);
mirror.start(*state, *trigger, *ns);
}
Op::CancelState(s) => {
real.cancel_state(*s);
mirror.cancel_state(*s);
}
Op::CancelOne { state, trigger } => {
real.cancel_one(*state, *trigger);
mirror.cancel_one(*state, *trigger);
}
Op::Decrement(elapsed) => {
real.decrement(core::time::Duration::from_nanos(*elapsed as u64));
mirror.decrement(*elapsed);
}
Op::PopExpired => {
let r = real.pop_expired(depth);
let m = mirror.pop_expired(depth);
assert_eq!(r, m, "step {i} PopExpired: real {r:?} vs mirror {m:?}");
}
Op::MinRemaining => {
let r = real.min_remaining().map(|d| d.as_nanos());
let m = mirror.min_remaining();
assert_eq!(r, m, "step {i} MinRemaining: real {r:?} vs mirror {m:?}");
}
Op::Len => {
assert_eq!(
real.entries.len(),
mirror.len(),
"step {i} Len mismatch"
);
}
}
}
#[test]
fn corr_new_is_empty() {
let real: RealTable<8> = RealTable::new();
let mirror: MirrorTable = MirrorTable::new();
assert_eq!(real.entries.len(), mirror.len());
assert_eq!(real.entries.is_empty(), mirror.is_empty());
}
#[test]
fn corr_timer_start_replaces_in_place() {
// Re-starting (1, 10) must not duplicate; the table has one entry for it.
assert_corresponds::<8>(
&[0, 1, 1, 1, 1, 1, 1, 1],
&[
Op::Start { state: 1, trigger: 10, ns: 100 },
Op::Len,
Op::Start { state: 1, trigger: 10, ns: 500 },
Op::Len, // still 1 entry
Op::MinRemaining,
],
);
}
#[test]
fn corr_timer_cancel_state_removes_only_matching() {
assert_corresponds::<8>(
&[0, 1, 1, 2],
&[
Op::Start { state: 1, trigger: 10, ns: 100 },
Op::Start { state: 1, trigger: 20, ns: 200 },
Op::Start { state: 2, trigger: 10, ns: 300 },
Op::CancelState(1),
Op::Len, // only state-2 survives
Op::PopExpired, // none expired
],
);
}
#[test]
fn corr_timer_cancel_one_targets_exact_pair() {
assert_corresponds::<8>(
&[0, 1, 1, 2],
&[
Op::Start { state: 1, trigger: 10, ns: 100 },
Op::Start { state: 1, trigger: 20, ns: 200 },
Op::Start { state: 2, trigger: 10, ns: 300 },
Op::CancelOne { state: 1, trigger: 10 },
Op::Len,
],
);
}
#[test]
fn corr_timer_decrement_to_zero_then_pop() {
assert_corresponds::<8>(
&[0, 1, 1, 1],
&[
Op::Start { state: 1, trigger: 10, ns: 500 },
Op::Decrement(200),
Op::MinRemaining, // 300
Op::Decrement(400), // saturates to 0
Op::MinRemaining, // 0
Op::PopExpired, // returns (1, 10)
Op::Len, // 0
Op::PopExpired, // None
],
);
}
#[test]
fn corr_timer_pop_picks_deepest() {
// Two expired timers at different depths. depth[1]=1, depth[2]=3.
// pop_expired must pick state 2 first (deeper).
assert_corresponds::<8>(
&[0, 1, 3, 0],
&[
Op::Start { state: 1, trigger: 100, ns: 0 },
Op::Start { state: 2, trigger: 200, ns: 0 },
Op::PopExpired, // (2, 200)
Op::PopExpired, // (1, 100)
Op::PopExpired, // None
],
);
}
#[test]
fn corr_timer_pop_breaks_tie_by_declaration_order() {
// depth[1]=2, depth[2]=2: equal depth, first-declared (1, 100) wins.
assert_corresponds::<8>(
&[0, 2, 2, 0],
&[
Op::Start { state: 1, trigger: 100, ns: 0 },
Op::Start { state: 2, trigger: 200, ns: 0 },
Op::PopExpired, // (1, 100)
Op::PopExpired, // (2, 200)
],
);
}
#[test]
fn corr_timer_min_remaining_is_smallest() {
assert_corresponds::<8>(
&[0, 1, 1, 1],
&[
Op::Start { state: 1, trigger: 1, ns: 9_999 },
Op::Start { state: 2, trigger: 2, ns: 100 },
Op::Start { state: 3, trigger: 3, ns: 5_000 },
Op::MinRemaining, // 100
],
);
}
#[test]
fn corr_timer_complex_sequence() {
assert_corresponds::<8>(
&[0, 1, 1, 2, 2, 3],
&[
Op::Start { state: 1, trigger: 1, ns: 1_000 },
Op::Start { state: 2, trigger: 1, ns: 2_000 },
Op::Start { state: 3, trigger: 1, ns: 3_000 },
Op::Decrement(1_500),
Op::MinRemaining, // 0 (state 1 hit zero)
Op::PopExpired, // (1, 1) — only one expired
Op::Decrement(600),
Op::PopExpired, // (2, 1) — now expired
Op::Len, // 1
Op::CancelState(3),
Op::Len, // 0
],
);
fn corr_default_is_empty() {
let real: RealTable<8> = RealTable::default();
let mirror: MirrorTable = MirrorTable::default();
assert_eq!(real.entries.len(), mirror.len());
assert!(mirror.is_empty());
assert!(real.entries.is_empty());
}