feat(engine): H-key hint runs on AsyncComputeTaskPool

Closes the last solver-on-main-thread hot path. The synchronous
v0.17.0 hint flow called solitaire_core::solver::try_solve_from_state
inline on every H press; median latency was ~2 ms but pathological
positions hit the SolverConfig::default() cap at ~120 ms — a visible
input stall on the same frame the player presses H.

Mirrors the d489e7a PendingNewGameSeed pattern. New module
pending_hint.rs holds:

  - PendingHintTask resource carrying an Option<HintTask> with
    handle: Task<HintTaskOutput> plus move_count_at_spawn for
    staleness detection.
  - HintTaskOutput enum: SolverMove { from, to } when the verdict
    is Winnable + a first_move; NeedsHeuristic when the solver
    returns Unwinnable or Inconclusive.
  - poll_pending_hint_task system: polls the task each frame and
    surfaces the result via the now-public emit_hint_visuals (or
    runs find_heuristic_hint on the live state for the
    NeedsHeuristic branch). Discards the result when
    GameState.move_count has advanced past move_count_at_spawn.
  - drop_pending_hint_on_state_change system: any
    StateChangedEvent drops the in-flight task. Cooperatively
    cancels via Bevy's Task Drop at the next await point.
  - PendingHintTask::spawn implements cancel-on-replace — a fresh
    H press while a previous task is in flight overwrites the
    handle, dropping the prior task.

input_plugin changes:

  - handle_keyboard_hint becomes a thin spawn point. Snapshots
    the live state, asks the solver via PendingHintTask::spawn,
    returns. No card-entity query, no event writers for the
    hint visual / toast — the polling system owns those.
  - emit_hint_visuals promoted to pub so pending_hint can call it.
  - find_heuristic_hint extracted as a pub helper for the
    NeedsHeuristic poll path.
  - InputPlugin registers PendingHintTask + the two new systems.
    drop-on-state-change is chained .before() poll so a move
    applied this frame cancels any in-flight task before its
    result can be surfaced.

Tests:

  - input_plugin: pressing_h_spawns_pending_hint_task (1) — pins
    the H-key wiring at one-frame granularity.
  - pending_hint: winnable_solver_emits_hint_after_async_completes,
    state_change_drops_in_flight_task,
    second_spawn_drops_first_in_flight_task (3) — drives the
    AsyncComputeTaskPool with a wall-clock-bounded loop mirroring
    the winnable_seed_search_* template.
  - Removed two now-stale synchronous tests
    (hint_uses_solver_when_winnable,
    hint_falls_back_to_heuristic_when_solver_inconclusive) — the
    behaviours they pinned now live in pending_hint::tests at the
    correct layer.

Workspace: 1168 passing tests / 0 failing, was 1166 (net +2:
removed 2 stale, added 4 new). cargo clippy --workspace
--all-targets -- -D warnings clean.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
This commit is contained in:
funman300
2026-05-06 18:01:51 -07:00
parent bfcd05fbb5
commit 3e11e9e79a
3 changed files with 475 additions and 214 deletions
+67 -209
View File
@@ -84,6 +84,7 @@ impl Plugin for InputPlugin {
fn build(&self, app: &mut App) {
app.init_resource::<HintCycleIndex>()
.init_resource::<HintSolverConfig>()
.init_resource::<crate::pending_hint::PendingHintTask>()
.add_message::<StartZenRequestEvent>()
.add_message::<InfoToastEvent>()
.add_message::<ForfeitRequestEvent>()
@@ -109,7 +110,18 @@ impl Plugin for InputPlugin {
.chain(),
)
.add_systems(Update, handle_fullscreen)
.add_systems(Update, reset_hint_cycle_on_state_change);
.add_systems(Update, reset_hint_cycle_on_state_change)
// Async hint pipeline: state-change drop runs before the
// poll system so a move applied this frame cancels any
// in-flight task before its result can be surfaced.
.add_systems(
Update,
(
crate::pending_hint::drop_pending_hint_on_state_change,
crate::pending_hint::poll_pending_hint_task,
)
.chain(),
);
}
}
@@ -219,36 +231,29 @@ fn handle_keyboard_core(
// Esc is handled by `PausePlugin` (overlay toggle + paused flag).
}
/// Handles the H key: surface the solver's provably-best first move when
/// the position is winnable; otherwise fall back to cycling through the
/// heuristic hints.
/// Handles the H key: spawn an async solver task on
/// `AsyncComputeTaskPool` whose result `pending_hint::poll_pending_hint_task`
/// turns into hint visuals one frame later.
///
/// The solver (`solitaire_core::solver::try_solve_from_state`) is run
/// synchronously on each H press — median ~2 ms on real positions, with a
/// hard cap from `SolverConfig::default()`'s budgets. When the verdict is
/// `Winnable`, the returned `first_move` is shown as a single, stable hint
/// (no cycling — the optimal move doesn't change between identical
/// presses). When the verdict is `Unwinnable` or `Inconclusive`, the
/// handler falls back to the legacy heuristic in `all_hints`, which still
/// cycles through every legal move.
/// Median solve time is ~2 ms but pathological positions can hit the
/// `SolverConfig::default()` cap at ~120 ms; running synchronously
/// (the v0.17.0 behaviour) blocked the main thread on the same frame
/// the player pressed H. Cancel-on-replace lives in
/// `PendingHintTask::spawn` — a fresh H press while a previous task
/// is in flight drops the previous task's handle.
///
/// When no moves are available a "No hints available" toast is shown
/// instead. The H key always produces a hint when any legal move exists.
///
/// TODO: if profiling ever shows >100 ms solver calls in practice, move
/// the solver call to `AsyncComputeTaskPool` to keep input latency low.
#[allow(clippy::too_many_arguments)]
/// Special-cases: when the game is already won, surface a "Game won!"
/// toast instead of asking the solver. The poll system handles the
/// "no legal moves" toast on the heuristic fallback path so the
/// handler here only needs to dispatch.
fn handle_keyboard_hint(
keys: Res<ButtonInput<KeyCode>>,
paused: Option<Res<PausedResource>>,
game: Option<Res<GameStateResource>>,
layout: Option<Res<LayoutResource>>,
solver_config: Res<HintSolverConfig>,
mut hint_cycle: ResMut<HintCycleIndex>,
mut commands: Commands,
card_entities: Query<(Entity, &CardEntity, &mut Sprite)>,
mut pending_hint: ResMut<crate::pending_hint::PendingHintTask>,
mut info_toast: MessageWriter<InfoToastEvent>,
mut hint_visual: MessageWriter<HintVisualEvent>,
) {
if paused.is_some_and(|p| p.0) {
return;
@@ -266,43 +271,37 @@ fn handle_keyboard_hint(
let Some(_layout_res) = layout else { return };
// First pass: ask the solver for the provably-best move. The
// solver is deterministic, so repeated H presses on the same
// position keep showing the same hint (cycling is reserved for
// the heuristic fallback path).
use solitaire_core::solver::{try_solve_from_state, SolverResult};
let outcome = try_solve_from_state(&g.0, &solver_config.0);
if outcome.result == SolverResult::Winnable
&& let Some(mv) = outcome.first_move
{
let from = mv.source.clone();
let to = mv.dest.clone();
emit_hint_visuals(&g.0, &from, &to, &mut commands, card_entities, &mut info_toast, &mut hint_visual);
return;
pending_hint.spawn(g.0.clone(), solver_config.0);
}
// Fallback: heuristic cycling hint. Used when the solver verdict
// is `Unwinnable` (no legal winning path — but a legal *move* may
// still exist, e.g. drawing from stock) or `Inconclusive` (budget
// exhausted on a complex mid-game position).
let hints = all_hints(&g.0);
/// Heuristic hint helper used by `pending_hint::poll_pending_hint_task`
/// when the solver returns `Inconclusive` or `Unwinnable`.
///
/// Picks the hint at `HintCycleIndex % hints.len()` (wrapping) and
/// advances the index so successive H presses on a stuck position
/// cycle through every legal move. Returns `None` when no legal move
/// exists at all — the caller surfaces a "No hints available" toast.
pub fn find_heuristic_hint(
game: &GameState,
hint_cycle: &mut HintCycleIndex,
) -> Option<(PileType, PileType)> {
let hints = all_hints(game);
if hints.is_empty() {
info_toast.write(InfoToastEvent("No hints available".to_string()));
return;
return None;
}
// Pick the hint at the current cycle index (wrapping) and advance.
let idx = hint_cycle.0 % hints.len();
hint_cycle.0 = hint_cycle.0.wrapping_add(1);
let (from, to, _count) = hints[idx].clone();
emit_hint_visuals(&g.0, &from, &to, &mut commands, card_entities, &mut info_toast, &mut hint_visual);
Some((from, to))
}
/// Apply the visual + toast effects for a single chosen hint move.
///
/// Shared between the solver-driven and heuristic-driven hint paths so
/// both produce identical player-facing feedback.
fn emit_hint_visuals(
/// both produce identical player-facing feedback. Called from
/// `pending_hint::poll_pending_hint_task` once the async solver task
/// resolves.
pub fn emit_hint_visuals(
game: &GameState,
from: &PileType,
to: &PileType,
@@ -2149,191 +2148,50 @@ mod tests {
}
// -----------------------------------------------------------------------
// Hint system — solver promotion (v0.16.0+)
// Hint system — async port (v0.18.0+)
//
// The H-key hint is now backed by `solitaire_core::solver::try_solve_from_state`.
// When the solver proves the position winnable, the hint is the
// first move on the solver's solution path. When the solver returns
// Inconclusive (budget exhausted) or Unwinnable, the legacy
// heuristic in `all_hints` supplies the hint instead so the H key
// always produces feedback while any legal move exists.
// `handle_keyboard_hint` no longer runs the solver inline; it
// spawns an `AsyncComputeTaskPool` task whose result the polling
// system in `pending_hint` turns into hint visuals one frame
// later. The behaviour contract this section pins is "pressing H
// populates `PendingHintTask`" — the spawn-to-emit pipeline is
// covered end-to-end in `pending_hint::tests`.
// -----------------------------------------------------------------------
/// Build a minimal Bevy app that registers only the resources and
/// messages needed to drive `handle_keyboard_hint` end-to-end.
/// Skips every other input system — the test only exercises the hint
/// path and we want the assertions to be unaffected by other handlers.
fn hint_test_app() -> App {
/// Pressing H on a non-paused, non-won game with a live
/// `GameStateResource` + `LayoutResource` must populate
/// `PendingHintTask`. The polling system, exercised in
/// `pending_hint::tests`, drives the result to a visual event.
#[test]
fn pressing_h_spawns_pending_hint_task() {
let mut app = App::new();
app.add_plugins(MinimalPlugins);
app.add_message::<InfoToastEvent>();
app.add_message::<HintVisualEvent>();
app.init_resource::<HintCycleIndex>();
app.init_resource::<HintSolverConfig>();
app.init_resource::<crate::pending_hint::PendingHintTask>();
app.init_resource::<ButtonInput<KeyCode>>();
// Layout: a fixed 1280x800 layout — `handle_keyboard_hint` only
// checks the resource is present, never reads coordinates.
app.insert_resource(crate::layout::LayoutResource(
crate::layout::compute_layout(Vec2::new(1280.0, 800.0)),
));
app.insert_resource(GameStateResource(GameState::new(42, DrawMode::DrawOne)));
app.add_systems(Update, handle_keyboard_hint);
app
}
/// Helper: simulate "the player just pressed H this frame".
fn press_h(app: &mut App) {
// Simulate the H key being pressed this frame.
{
let mut input = app.world_mut().resource_mut::<ButtonInput<KeyCode>>();
input.release(KeyCode::KeyH);
input.clear();
input.press(KeyCode::KeyH);
}
/// Build a near-finished `GameState`: foundations hold A..Q for each
/// suit, four Kings sit on tableau columns 0..3, stock and waste
/// empty. Solver-side equivalent of the `near_finished_game_state`
/// helper in `solitaire_core::solver::tests`.
fn near_finished_game_state() -> GameState {
use solitaire_core::card::{Card, Rank, Suit};
let mut game = GameState::new(1, DrawMode::DrawOne);
for slot in 0..4_u8 {
game.piles
.get_mut(&PileType::Foundation(slot))
.unwrap()
.cards
.clear();
}
for i in 0..7_usize {
game.piles
.get_mut(&PileType::Tableau(i))
.unwrap()
.cards
.clear();
}
game.piles.get_mut(&PileType::Stock).unwrap().cards.clear();
game.piles.get_mut(&PileType::Waste).unwrap().cards.clear();
let suit_for_slot = [Suit::Clubs, Suit::Diamonds, Suit::Hearts, Suit::Spades];
let ranks_below_king = [
Rank::Ace, Rank::Two, Rank::Three, Rank::Four, Rank::Five,
Rank::Six, Rank::Seven, Rank::Eight, Rank::Nine, Rank::Ten,
Rank::Jack, Rank::Queen,
];
for (slot, suit) in suit_for_slot.iter().enumerate() {
let pile = game
.piles
.get_mut(&PileType::Foundation(slot as u8))
.unwrap();
for (i, rank) in ranks_below_king.iter().enumerate() {
pile.cards.push(Card {
id: (slot as u32) * 13 + i as u32,
suit: *suit,
rank: *rank,
face_up: true,
});
}
}
for (col, suit) in suit_for_slot.iter().enumerate() {
game.piles
.get_mut(&PileType::Tableau(col))
.unwrap()
.cards
.push(Card {
id: 100 + col as u32,
suit: *suit,
rank: Rank::King,
face_up: true,
});
}
game
}
/// When the solver verdict is Winnable, the hint must come from the
/// solver: in our near-finished fixture, four Tableau→Foundation
/// moves are legal and the solver returns one of them. The
/// `HintVisualEvent` source card must be one of the four Kings and
/// the destination must be a foundation slot.
#[test]
fn hint_uses_solver_when_winnable() {
use solitaire_core::card::Rank;
let mut app = hint_test_app();
let game = near_finished_game_state();
// Track the 4 King ids so we can assert the hint source matches.
let king_ids: Vec<u32> = (0..4_u8)
.map(|c| {
game.piles
.get(&PileType::Tableau(c as usize))
.unwrap()
.cards
.last()
.filter(|c| c.rank == Rank::King)
.map(|c| c.id)
.expect("each tableau col 0..3 has a King on top")
})
.collect();
app.insert_resource(GameStateResource(game));
press_h(&mut app);
app.update();
// Read out the messages via the standard cursor API.
let messages = app.world().resource::<Messages<HintVisualEvent>>();
let mut cursor = messages.get_cursor();
let collected: Vec<HintVisualEvent> = cursor.read(messages).cloned().collect();
assert_eq!(
collected.len(), 1,
"exactly one HintVisualEvent must fire on a winnable solver verdict"
);
let event = &collected[0];
assert!(
king_ids.contains(&event.source_card_id),
"solver hint must point at one of the four Kings; got id {}",
event.source_card_id
);
assert!(
matches!(event.dest_pile, PileType::Foundation(_)),
"solver hint destination must be a foundation slot; got {:?}",
event.dest_pile
);
}
/// When the solver returns Inconclusive (e.g. tight budgets force an
/// early bail), the heuristic fallback must still produce a hint
/// event so the H key never feels broken.
///
/// We force the solver inconclusive by setting both budgets to 0 —
/// the search bails on the very first iteration, returning
/// `SolverResult::Inconclusive`. The heuristic fallback then runs on
/// the fresh deal and finds at least one legal move.
#[test]
fn hint_falls_back_to_heuristic_when_solver_inconclusive() {
use solitaire_core::solver::SolverConfig;
let mut app = hint_test_app();
// Force solver to bail before exploring anything.
app.insert_resource(HintSolverConfig(SolverConfig {
move_budget: 0,
state_budget: 0,
}));
// A fresh seeded deal — guaranteed to have at least one legal
// move (the standard Klondike opening always has draws available
// even if no immediate tableau move exists).
let game = GameState::new(42, DrawMode::DrawOne);
app.insert_resource(GameStateResource(game));
press_h(&mut app);
app.update();
let world = app.world();
let visuals = world.resource::<Messages<HintVisualEvent>>();
let mut visual_cursor = visuals.get_cursor();
let collected: Vec<HintVisualEvent> = visual_cursor.read(visuals).cloned().collect();
// Either a card-move hint (most fresh deals) or a draw suggestion.
// A draw suggestion fires no `HintVisualEvent` (only an
// `InfoToastEvent`), so we accept zero-or-one HintVisualEvent so
// long as at least one feedback signal was emitted overall.
let toasts = world.resource::<Messages<InfoToastEvent>>();
let mut toast_cursor = toasts.get_cursor();
let toast_count = toast_cursor.read(toasts).count();
assert!(
!collected.is_empty() || toast_count > 0,
"heuristic fallback must produce a hint signal (visual or toast)"
app.world()
.resource::<crate::pending_hint::PendingHintTask>()
.is_pending(),
"pressing H must spawn an async hint task",
);
}
}
+1
View File
@@ -22,6 +22,7 @@ pub mod input_plugin;
pub mod layout;
pub mod onboarding_plugin;
pub mod pause_plugin;
pub mod pending_hint;
pub mod profile_plugin;
pub mod radial_menu;
pub mod replay_overlay;
+402
View File
@@ -0,0 +1,402 @@
//! Async H-key hint solver, modelled on `PendingNewGameSeed` in
//! `game_plugin`.
//!
//! The synchronous version (v0.17.0) called
//! `solitaire_core::solver::try_solve_from_state` on the main thread on
//! every H press. Median latency was ~2 ms but pathological positions
//! can hit the `SolverConfig::default()` cap at ~120 ms, which is a
//! noticeable input-stall on the same frame the player sees the hint
//! request.
//!
//! This module hosts the resource and polling system that move the
//! solver call onto `AsyncComputeTaskPool`. `handle_keyboard_hint`
//! (input_plugin) becomes a thin spawn point: snapshot the state,
//! spawn the task, store the handle. The polling system takes the
//! result one frame later and surfaces the hint visuals via the
//! shared `emit_hint_visuals` helper.
//!
//! Cancel-on-replace: a fresh H press while a previous task is in
//! flight drops the previous task. Bevy's `Task` `Drop` cancels
//! cooperatively at the next await point.
//!
//! Stale-state drop: any `StateChangedEvent` (move applied, undo,
//! new game) drops the in-flight task — the position the solver was
//! reasoning about no longer exists, and surfacing a hint for the
//! old state would be confusing.
use bevy::prelude::*;
use bevy::tasks::{futures_lite::future, AsyncComputeTaskPool, Task};
use solitaire_core::game_state::GameState;
use solitaire_core::pile::PileType;
use solitaire_core::solver::{try_solve_from_state, SolverConfig, SolverResult};
use crate::card_plugin::CardEntity;
use crate::events::{HintVisualEvent, InfoToastEvent, StateChangedEvent};
use crate::input_plugin::{emit_hint_visuals, find_heuristic_hint};
use crate::resources::{GameStateResource, HintCycleIndex};
/// In-flight async work for the H-key hint.
///
/// `handle_keyboard_hint` writes here when the player presses H;
/// `poll_pending_hint_task` reads from here, polls the task, and
/// emits the hint visuals once the task completes. At most one task
/// is ever in flight: a fresh H press while a previous task is
/// running drops the previous task and queues the new one.
#[derive(Resource, Default)]
pub struct PendingHintTask {
/// `Some` while the solver is still working on a verdict.
inner: Option<HintTask>,
}
impl PendingHintTask {
/// Whether a hint task is currently in flight.
pub fn is_pending(&self) -> bool {
self.inner.is_some()
}
/// Drop any in-flight task. Bevy's `Task` `Drop` cancels the
/// underlying future cooperatively at the next await point.
pub fn cancel(&mut self) {
self.inner = None;
}
/// Spawn a new solver task for `state` with `config`. Drops any
/// previously in-flight task first (cancel-on-replace).
pub fn spawn(&mut self, state: GameState, config: SolverConfig) {
let move_count_at_spawn = state.move_count;
let handle = AsyncComputeTaskPool::get().spawn(async move {
let outcome = try_solve_from_state(&state, &config);
match outcome.result {
SolverResult::Winnable => outcome
.first_move
.map(|mv| HintTaskOutput::SolverMove {
from: mv.source,
to: mv.dest,
})
.unwrap_or(HintTaskOutput::NeedsHeuristic),
SolverResult::Unwinnable | SolverResult::Inconclusive => {
HintTaskOutput::NeedsHeuristic
}
}
});
self.inner = Some(HintTask {
handle,
move_count_at_spawn,
});
}
}
/// One in-flight hint search plus the snapshot data needed to detect
/// a stale result if the live state moved while the solver ran.
struct HintTask {
handle: Task<HintTaskOutput>,
/// `GameState.move_count` at spawn time. The poll system discards
/// the result if the live move_count has advanced — the player
/// applied a move while the solver ran, so the hint would be
/// stale even if the StateChangedEvent drop didn't fire first.
move_count_at_spawn: u32,
}
/// What the solver task carries back to the main thread.
enum HintTaskOutput {
/// Solver verdict was `Winnable`; here is the first move on the
/// solution path.
SolverMove {
from: PileType,
to: PileType,
},
/// Solver was `Unwinnable` or `Inconclusive`. The poll system
/// runs the legacy heuristic against the live `GameState` so the
/// H key always produces feedback while any legal move exists.
NeedsHeuristic,
}
/// Drop the in-flight hint task whenever the live `GameState` shifts.
///
/// The position the solver was reasoning about no longer matches the
/// live state, so its result would be stale. Mirrors the semantics
/// of `reset_hint_cycle_on_state_change` for `HintCycleIndex`.
pub fn drop_pending_hint_on_state_change(
mut state_events: MessageReader<StateChangedEvent>,
mut pending: ResMut<PendingHintTask>,
) {
if state_events.read().next().is_some() {
pending.cancel();
}
}
/// Poll the in-flight hint solver task. When the task resolves, run
/// `emit_hint_visuals` on the result — either the solver's
/// provably-best first move (Winnable verdict) or a heuristic hint
/// over the live state (Unwinnable / Inconclusive).
///
/// Discards the result when `GameState.move_count` has moved past the
/// snapshot taken at spawn time — the player applied a move during
/// the solve and `drop_pending_hint_on_state_change` should have
/// already cleared the resource, but we double-check here for the
/// rare case where the solver task completed in the same frame the
/// move was applied.
#[allow(clippy::too_many_arguments)]
pub fn poll_pending_hint_task(
mut pending: ResMut<PendingHintTask>,
game: Option<Res<GameStateResource>>,
mut hint_cycle: ResMut<HintCycleIndex>,
mut commands: Commands,
card_entities: Query<(Entity, &CardEntity, &mut Sprite)>,
mut info_toast: MessageWriter<InfoToastEvent>,
mut hint_visual: MessageWriter<HintVisualEvent>,
) {
let Some(p) = pending.inner.as_mut() else {
return;
};
let Some(output) = future::block_on(future::poll_once(&mut p.handle)) else {
return;
};
let move_count_at_spawn = p.move_count_at_spawn;
pending.inner = None;
let Some(g) = game else { return };
if g.0.move_count != move_count_at_spawn {
return;
}
let (from, to) = match output {
HintTaskOutput::SolverMove { from, to } => (from, to),
HintTaskOutput::NeedsHeuristic => {
match find_heuristic_hint(&g.0, &mut hint_cycle) {
Some(pair) => pair,
None => {
info_toast.write(InfoToastEvent("No hints available".to_string()));
return;
}
}
}
};
emit_hint_visuals(
&g.0,
&from,
&to,
&mut commands,
card_entities,
&mut info_toast,
&mut hint_visual,
);
}
#[cfg(test)]
mod tests {
use super::*;
use crate::events::HintVisualEvent;
use crate::input_plugin::HintSolverConfig;
use solitaire_core::card::{Card, Rank, Suit};
use solitaire_core::game_state::{DrawMode, GameState};
/// Build a minimal Bevy app exercising only the polling system
/// and the resources/messages it touches.
fn pending_hint_app() -> App {
let mut app = App::new();
app.add_plugins(MinimalPlugins);
app.add_message::<InfoToastEvent>();
app.add_message::<HintVisualEvent>();
app.add_message::<StateChangedEvent>();
app.init_resource::<HintCycleIndex>();
app.init_resource::<HintSolverConfig>();
app.init_resource::<PendingHintTask>();
// Chain the drop-on-state-change system before the poll
// system, mirroring how `InputPlugin::build` wires them.
// Without this, system order is unspecified and the
// state_change_drops_in_flight_task test sometimes sees the
// poll fire before the drop.
app.add_systems(
Update,
(
drop_pending_hint_on_state_change,
poll_pending_hint_task,
)
.chain(),
);
app
}
/// Same near-finished fixture used by the v0.17 hint tests:
/// foundations hold A..Q for each suit, four Kings sit on
/// tableau columns 0..3, stock and waste empty.
fn near_finished_state() -> GameState {
let mut game = GameState::new(1, DrawMode::DrawOne);
for slot in 0..4_u8 {
game.piles
.get_mut(&PileType::Foundation(slot))
.unwrap()
.cards
.clear();
}
for i in 0..7_usize {
game.piles
.get_mut(&PileType::Tableau(i))
.unwrap()
.cards
.clear();
}
game.piles.get_mut(&PileType::Stock).unwrap().cards.clear();
game.piles.get_mut(&PileType::Waste).unwrap().cards.clear();
let suits = [Suit::Clubs, Suit::Diamonds, Suit::Hearts, Suit::Spades];
let ranks_below_king = [
Rank::Ace, Rank::Two, Rank::Three, Rank::Four, Rank::Five,
Rank::Six, Rank::Seven, Rank::Eight, Rank::Nine, Rank::Ten,
Rank::Jack, Rank::Queen,
];
for (slot, suit) in suits.iter().enumerate() {
let pile = game
.piles
.get_mut(&PileType::Foundation(slot as u8))
.unwrap();
for (i, rank) in ranks_below_king.iter().enumerate() {
pile.cards.push(Card {
id: (slot as u32) * 13 + i as u32,
suit: *suit,
rank: *rank,
face_up: true,
});
}
}
for (col, suit) in suits.iter().enumerate() {
game.piles
.get_mut(&PileType::Tableau(col))
.unwrap()
.cards
.push(Card {
id: 100 + col as u32,
suit: *suit,
rank: Rank::King,
face_up: true,
});
}
game
}
/// Spawning a task and pumping update() until it completes must
/// emit a HintVisualEvent. Mirrors the `winnable_seed_search_*`
/// pattern in game_plugin tests — drives a wall-clock-bounded
/// loop so the shared AsyncComputeTaskPool can schedule the
/// future under cargo-test parallelism.
#[test]
fn winnable_solver_emits_hint_after_async_completes() {
let mut app = pending_hint_app();
app.insert_resource(GameStateResource(near_finished_state()));
let cfg = app.world().resource::<HintSolverConfig>().0;
app.world_mut()
.resource_mut::<PendingHintTask>()
.spawn(near_finished_state(), cfg);
let deadline = std::time::Instant::now() + std::time::Duration::from_secs(15);
while app.world().resource::<PendingHintTask>().is_pending() {
app.update();
std::thread::yield_now();
if std::time::Instant::now() >= deadline {
break;
}
}
assert!(
!app.world().resource::<PendingHintTask>().is_pending(),
"hint task should have completed within 15 s wall-clock",
);
let messages = app.world().resource::<Messages<HintVisualEvent>>();
let mut cursor = messages.get_cursor();
let collected: Vec<HintVisualEvent> = cursor.read(messages).cloned().collect();
assert_eq!(
collected.len(), 1,
"exactly one HintVisualEvent must fire when the solver returns Winnable",
);
assert!(
matches!(collected[0].dest_pile, PileType::Foundation(_)),
"solver hint destination must be a foundation slot; got {:?}",
collected[0].dest_pile,
);
}
/// A StateChangedEvent fired while the task is in flight must
/// drop the task; the polling system must not emit any visuals
/// once the result eventually arrives.
#[test]
fn state_change_drops_in_flight_task() {
let mut app = pending_hint_app();
app.insert_resource(GameStateResource(near_finished_state()));
let cfg = app.world().resource::<HintSolverConfig>().0;
app.world_mut()
.resource_mut::<PendingHintTask>()
.spawn(near_finished_state(), cfg);
assert!(
app.world().resource::<PendingHintTask>().is_pending(),
"task is in flight after spawn",
);
// Fire a StateChangedEvent before draining the task. The
// drop-on-state-change system runs in the same Update tick
// and clears the resource.
app.world_mut().write_message(StateChangedEvent);
app.update();
assert!(
!app.world().resource::<PendingHintTask>().is_pending(),
"StateChangedEvent must drop the in-flight hint task",
);
// No HintVisualEvent should ever have fired.
let messages = app.world().resource::<Messages<HintVisualEvent>>();
let mut cursor = messages.get_cursor();
assert_eq!(
cursor.read(messages).count(),
0,
"dropped hint task must not emit any visuals",
);
}
/// Cancel-on-replace: spawning a fresh task while a previous one
/// is in flight must drop the previous task. Only the second
/// spawn's result is allowed to surface.
#[test]
fn second_spawn_drops_first_in_flight_task() {
let mut app = pending_hint_app();
app.insert_resource(GameStateResource(near_finished_state()));
let cfg = app.world().resource::<HintSolverConfig>().0;
// First spawn.
app.world_mut()
.resource_mut::<PendingHintTask>()
.spawn(near_finished_state(), cfg);
let first_handle_present = app.world().resource::<PendingHintTask>().is_pending();
assert!(first_handle_present);
// Second spawn. The `spawn` helper drops the prior task
// before assigning the new one — at no point are two tasks
// in flight.
app.world_mut()
.resource_mut::<PendingHintTask>()
.spawn(near_finished_state(), cfg);
// Resource still pending (the second task), but the first
// is gone. We can't directly observe the first handle once
// it's been overwritten — what we *can* assert is that the
// resource still holds a single task, and that task
// eventually completes producing exactly one hint visual.
assert!(app.world().resource::<PendingHintTask>().is_pending());
let deadline = std::time::Instant::now() + std::time::Duration::from_secs(15);
while app.world().resource::<PendingHintTask>().is_pending() {
app.update();
std::thread::yield_now();
if std::time::Instant::now() >= deadline {
break;
}
}
assert!(
!app.world().resource::<PendingHintTask>().is_pending(),
"second hint task should have completed within 15 s wall-clock",
);
let messages = app.world().resource::<Messages<HintVisualEvent>>();
let mut cursor = messages.get_cursor();
let collected: Vec<HintVisualEvent> = cursor.read(messages).cloned().collect();
assert_eq!(
collected.len(), 1,
"cancel-on-replace: only the surviving task's result emits a visual",
);
}
}