turbo_tasks/
lib.rs

1#![doc = include_str!("../README.md")]
2#![feature(trivial_bounds)]
3#![feature(min_specialization)]
4#![deny(unsafe_op_in_unsafe_fn)]
5#![feature(error_generic_member_access)]
6#![feature(arbitrary_self_types)]
7#![feature(arbitrary_self_types_pointers)]
8#![feature(ptr_metadata)]
9#![feature(exclusive_wrapper)]
10#![feature(sync_unsafe_cell)]
11#![feature(async_fn_traits)]
12#![feature(impl_trait_in_assoc_type)]
13#![feature(const_type_name)]
14#![feature(mpmc_channel)]
15
16pub mod backend;
17mod capture_future;
18mod collectibles;
19mod completion;
20pub mod debug;
21#[doc = include_str!("../FORMATTING.md")]
22pub mod display;
23pub mod duration_span;
24mod dyn_task_inputs;
25mod effect;
26mod error;
27pub mod event;
28pub mod graph;
29mod id;
30mod id_factory;
31mod invalidation;
32mod join_iter_ext;
33pub mod keyed;
34mod local_task_tracker;
35#[doc(hidden)]
36pub mod macro_helpers;
37mod manager;
38pub mod mapped_read_ref;
39mod marker_trait;
40pub mod message_queue;
41mod native_function;
42mod once_map;
43mod output;
44pub mod panic_hooks;
45pub mod parallel;
46pub mod primitives;
47mod priority_runner;
48mod read_options;
49mod read_ref;
50pub mod registry;
51pub mod scope_bounded;
52pub mod scope_unbounded;
53mod serialization_invalidation;
54pub mod small_duration;
55mod spawn;
56mod state;
57pub mod task;
58#[cfg(feature = "task_dirty_cause")]
59mod task_dirty_cause;
60mod task_execution_reason;
61pub mod task_statistics;
62pub mod trace;
63mod trait_ref;
64mod triomphe_utils;
65pub mod util;
66mod value;
67mod value_type;
68mod vc;
69
70use std::hash::BuildHasherDefault;
71
72pub use anyhow::{Error, Result};
73use auto_hash_map::AutoSet;
74use rustc_hash::FxHasher;
75pub use shrink_to_fit::ShrinkToFit;
76pub use turbo_tasks_macros::{DeterministicHash, turbobail, turbofmt};
77
78#[cfg(feature = "task_dirty_cause")]
79pub use crate::task_dirty_cause::TaskDirtyCause;
80pub use crate::{
81    capture_future::TurboTasksPanic,
82    collectibles::CollectiblesSource,
83    completion::{Completion, Completions},
84    display::{ValueToString, ValueToStringRef},
85    dyn_task_inputs::{
86        DynTaskInputs, DynTaskInputsStorage, HeapDynTaskInputsStorage, StackDynTaskInputsStorage,
87    },
88    effect::{
89        ApplyError, CapturedEffect, Effect, EffectError, EffectExt, EffectStateStorage, Effects,
90        EffectsError, read_strongly_consistent_and_apply_effects,
91        resolve_strongly_consistent_and_take_and_apply_effects, take_effects,
92    },
93    error::PrettyPrintError,
94    id::{
95        ExecutionId, FunctionId, LocalTaskId, TRANSIENT_TASK_BIT, TaskId, TraitTypeId, ValueTypeId,
96    },
97    invalidation::{
98        InvalidationReason, InvalidationReasonKind, InvalidationReasonSet, Invalidator,
99        get_invalidator,
100    },
101    join_iter_ext::{JoinIterExt, TryFlatJoinIterExt, TryJoinIterExt},
102    manager::{
103        CurrentCellRef, InputResolution, ReadCellTracking, ReadConsistency, ReadTracking,
104        TaskPersistence, TaskPriority, TurboTasks, TurboTasksApi, TurboTasksCallApi, Unused,
105        UpdateInfo, dynamic_call, emit, get_serialization_invalidator, mark_finished,
106        mark_stateful, mark_top_level_task, prevent_gc, run, run_once, run_once_with_reason,
107        trait_call, turbo_tasks, turbo_tasks_scope, turbo_tasks_weak,
108        unmark_top_level_task_may_leak_eventually_consistent_state, with_turbo_tasks,
109    },
110    mapped_read_ref::MappedReadRef,
111    output::OutputContent,
112    read_options::{ReadCellOptions, ReadOutputOptions},
113    read_ref::ReadRef,
114    serialization_invalidation::SerializationInvalidator,
115    spawn::{JoinHandle, block_for_future, block_in_place, spawn, spawn_blocking, spawn_thread},
116    state::{State, parking_lot_mutex_bincode},
117    task::{
118        SharedReference, TypedSharedReference,
119        task_input::{EitherTaskInput, TaskInput},
120    },
121    task_execution_reason::TaskExecutionReason,
122    trait_ref::TraitRef,
123    value::{TransientInstance, TransientValue},
124    value_type::{Evictability, TraitMethod, TraitType, ValueType, ValueTypePersistence},
125    vc::{
126        CellId, Dynamic, NonLocalValue, OperationValue, OperationVc, OptionVcExt, OrdResolvedVc,
127        RawVc, RawVcUnpacked, ReadRawVcFuture, ReadVcFuture, ResolveOperationVcFuture,
128        ResolveRawVcFuture, ResolveVcFuture, ResolvedVc, ToResolvedVcFuture, Upcast, UpcastStrict,
129        ValueDefault, Vc, VcCast, VcCellCompareMode, VcCellHashedCompareMode,
130        VcCellKeyedCompareMode, VcCellNewMode, VcDefaultRead, VcRead, VcTransparentRead,
131        VcValueTrait, VcValueTraitCast, VcValueType, VcValueTypeCast,
132    },
133};
134
135pub type FxIndexSet<T> = indexmap::IndexSet<T, BuildHasherDefault<FxHasher>>;
136pub type FxIndexMap<K, V> = indexmap::IndexMap<K, V, BuildHasherDefault<FxHasher>>;
137pub type FxDashMap<K, V> = dashmap::DashMap<K, V, BuildHasherDefault<FxHasher>>;
138
139// Copied from indexmap! and indexset!
140#[macro_export]
141macro_rules! fxindexmap {
142    (@single $($x:tt)*) => (());
143    (@count $($rest:expr),*) => (<[()]>::len(&[$($crate::fxindexmap!(@single $rest)),*]));
144
145    ($($key:expr => $value:expr,)+) => { $crate::fxindexmap!($($key => $value),+) };
146    ($($key:expr => $value:expr),*) => {
147        {
148            let _cap = $crate::fxindexmap!(@count $($key),*);
149            let mut _map = $crate::FxIndexMap::with_capacity_and_hasher(_cap, Default::default());
150            $(
151                _map.insert($key, $value);
152            )*
153            _map
154        }
155    };
156}
157#[macro_export]
158macro_rules! fxindexset {
159    (@single $($x:tt)*) => (());
160    (@count $($rest:expr),*) => (<[()]>::len(&[$($crate::fxindexset!(@single $rest)),*]));
161
162    ($($value:expr,)+) => { $crate::fxindexset!($($value),+) };
163    ($($value:expr),*) => {
164        {
165            let _cap = $crate::fxindexset!(@count $($value),*);
166            let mut _set = $crate::FxIndexSet::with_capacity_and_hasher(_cap, Default::default());
167            $(
168                _set.insert($value);
169            )*
170            _set
171        }
172    };
173}
174
175#[doc = include_str!("../singleton_pattern.md")]
176pub mod _singleton_pattern {}
177
178#[doc = include_str!("../function.md")]
179#[rustfmt::skip]
180pub use turbo_tasks_macros::function;
181
182/// Implements [`VcValueType`] for the given `struct` or `enum`. These value types can be used
183/// inside of a "value cell" as [`Vc<...>`][Vc].
184///
185/// A [`Vc`] represents the result of a computation. Each [`Vc`]'s value is placed into a cell
186/// associated with the current [`TaskId`]. That [`Vc`] object can be `await`ed to get [a read-only
187/// reference to the value contained in the cell][ReadRef].
188///
189/// This macro accepts multiple comma-separated arguments. For example:
190///
191/// ```
192/// # #![feature(arbitrary_self_types)]
193//  # #![feature(arbitrary_self_types_pointers)]
194/// #[turbo_tasks::value(transparent, shared)]
195/// struct Foo(Vec<u32>);
196/// ```
197///
198/// ## `cell = "..."`
199///
200/// Controls when a cell is invalidated upon recomputation of a task. Internally, this is performed
201/// by setting the [`VcValueType::CellMode`] associated type.
202///
203/// - **`"new"`:** Always overrides the value in the cell, invalidating all dependent tasks.
204/// - **`"compare"` *(default)*:** Compares with the existing value in the cell, before overriding it.
205///   Requires the value to implement [`Eq`].
206/// - **`"keyed"`:** Like `"compare"`, but uses per-key invalidation for transparent map types.
207///
208/// Avoiding unnecessary invalidation is important to reduce downstream recomputation of tasks that
209/// depend on this cell's value.
210///
211/// Use `"new"` only if a correct implementation of [`Eq`] is not possible, would be expensive (e.g.
212/// would require comparing a large collection), or if you're implementing a low-level primitive
213/// that intentionally forces recomputation.
214///
215/// ## `eq = "..."`
216///
217/// By default, we `#[derive(PartialEq, Eq)]`. [`Eq`] is required by `cell = "compare"`. This
218/// argument allows overriding that default implementation behavior.
219///
220/// - **`"manual"`:** Prevents deriving [`Eq`] and [`PartialEq`] so you can do it manually.
221///
222/// ## `serialization = "..."`
223///
224/// Affects serialization via [`bincode::Encode`] and [`bincode::Decode`]. Serialization is required
225/// for the filesystem cache of tasks.
226///
227/// - **`"auto"` *(default)*:** Derives the bincode traits and enables serialization.
228/// - **`"custom"`:** Prevents deriving the bincode traits, but still enables serialization
229///   (you must manually implement [`bincode::Encode`] and [`bincode::Decode`]).
230/// - **`"hash"`:** Like `"none"` (no bincode serialization), but instead stores a hash of the cell
231///   value so that changes can be detected even when the transient cell data has been evicted
232///   from memory or was never stored in the cache—avoiding unnecessary downstream invalidation.
233///   Only valid with `cell = "compare"`.
234///   Requires the value to implement both [`Eq`] and [`DeterministicHash`][turbo_tasks_hash::DeterministicHash].
235/// - **`"none"`:** Disables serialization and prevents deriving the traits.
236///
237/// ## `hash = "..."`
238///
239/// By default, when using `serialization = "hash"`, we `#[derive(DeterministicHash)]`. This argument allows
240/// overriding that default implementation behavior.
241///
242/// - **`"manual"`:** Prevents deriving [`DeterministicHash`][turbo_tasks_hash::DeterministicHash] so you can do it manually.
243///   Only valid with `serialization = "hash"`.
244///
245/// ## `shared`
246///
247/// This flag makes the macro-generated `.cell()` method public so everyone can use it.
248///
249/// Non-transparent types are given a `.cell()` method. That method returns a `Vc` of the type.
250///
251/// This option does not apply to wrapper types that use `transparent`. Those use the public
252/// [`Vc::cell`] function for construction.
253///
254/// ## `transparent`
255///
256/// This attribute is only valid on single-element unit structs. When this value is set:
257///
258/// 1. The struct will use [`#[repr(transparent)]`][repr-transparent].
259/// 1. Read operations (`vc.await?`) return a [`ReadRef`] containing the inner type, rather than the
260///    outer struct. Internally, this is accomplished using [`VcTransparentRead`] for the
261///    [`VcValueType::Read`] associated type.
262/// 1. Construction of the type must be performed using [`Vc::cell(inner)`][Vc::cell], rather than
263///    using the `.cell()` method on the outer type (`outer.cell()`).
264/// 1. The [`ValueDebug`][crate::debug::ValueDebug] implementation will defer to the inner type.
265///
266/// This is commonly used to create [`VcValueType`] wrappers for foreign or generic types, such as
267/// [`Vec`] or [`Option`].
268///
269/// [repr-transparent]: https://doc.rust-lang.org/nomicon/other-reprs.html#reprtransparent
270///
271/// ## `local`
272///
273/// Skip the implementation of [`NonLocalValue`] for this type.
274///
275/// If not specified, we apply the [`#[derive(NonLocalValue)]`][macro@NonLocalValue] macro, which
276/// asserts that this struct has no fields containing [`Vc`] by implementing the [`NonLocalValue`]
277/// marker trait. Compile-time assertions are generated on every field, checking that they are also
278/// [`NonLocalValue`]s.
279#[rustfmt::skip]
280pub use turbo_tasks_macros::value;
281
282/// Attribute macro for declaring a [`TaskInput`] type. Emits:
283///
284/// - `unsafe impl NonLocalValue for X {}` (unless `contains_unresolved_vcs` is set).
285/// - `impl TaskInput for X` with a field-walking `is_transient`. By default `is_resolved` and
286///   `resolve_input` use the trait defaults (`true` and a [`CloneReady`] future — 8 bytes, no
287///   async-fn envelope); when `contains_unresolved_vcs` is set, both are emitted as
288///   field-walking implementations as well.
289///
290/// Default form (most types):
291///
292/// ```ignore
293/// #[turbo_tasks::task_input]
294/// #[derive(Clone, Debug, Hash, PartialEq, Eq, TraceRawVcs, Encode, Decode)]
295/// pub struct MyTaskInput { ... }
296/// ```
297///
298/// Opt out of `NonLocalValue` when the type contains `Vc<T>` fields:
299///
300/// ```ignore
301/// #[turbo_tasks::task_input(contains_unresolved_vcs)]
302/// #[derive(Clone, Debug, Hash, PartialEq, Eq, TraceRawVcs, Encode, Decode)]
303/// pub struct VcCarrier { vc: Vc<...> }
304/// ```
305pub use turbo_tasks_macros::task_input;
306
307/// Allows this trait to be used as part of a trait object inside of a value cell, in the form of
308/// `Vc<Box<dyn MyTrait>>`. The annotated trait is made into a subtrait of [`VcValueTrait`].
309///
310/// ```ignore
311/// #[turbo_tasks::value_trait]
312/// pub trait MyTrait {
313///
314///     #[turbo_tasks::function]
315///     fn method(self: Vc<Self>, a: i32) -> Vc<Something>;
316///
317///     // External signature: fn method(self: Vc<Self>, a: i32) -> Vc<Something>
318///     #[turbo_tasks::function]
319///     async fn method2(&self, a: i32) -> Result<Vc<Something>> {
320///         // Default implementation
321///     }
322///
323///     // A normal trait item, not a turbo-task
324///     fn normal(&self) -> SomethingElse;
325/// }
326///
327/// #[turbo_tasks::value_trait]
328/// pub trait OtherTrait: MyTrait + ValueToString {
329///     // ...
330/// }
331///
332/// #[turbo_tasks::value_impl]
333/// impl MyTrait for MyValue {
334///     // only the external signature must match (see the docs for #[turbo_tasks::function])
335///     #[turbo_tasks::function]
336///     fn method(&self, a: i32) -> Vc<Something> {
337///         todo!()
338///     }
339///
340///     fn normal(&self) -> SomethingElse {
341///         todo!()
342///     }
343/// }
344/// ```
345///
346/// The `#[turbo_tasks::value_trait]` annotation derives [`VcValueTrait`] and registers the trait
347/// and its methods.
348///
349/// All methods annotated with [`#[turbo_tasks::function]`][function] are cached, and
350/// the external signature rewriting rules defined on that macro are applied.
351///
352/// Default implementation are supported.
353///
354/// ## Arguments
355///
356/// Example: `#[turbo_tasks::value_trait(no_debug, operation)]`
357///
358/// ### `no_debug`
359///
360/// Disables the automatic implementation of [`ValueDebug`][debug::ValueDebug].
361///
362/// Example: `#[turbo_tasks::value_trait(no_debug)]`
363///
364/// ### `Operation`
365///
366/// Adds [`OperationValue`] as a supertrait of this trait.
367///
368/// Example: `#[turbo_tasks::value_trait(operation)]`
369#[rustfmt::skip]
370pub use turbo_tasks_macros::value_trait;
371
372/// A macro used on any `impl` block for a [`VcValueType`]. This can either be an inherent
373/// implementation or a trait implementation (see [`turbo_tasks::value_trait`][value_trait] and
374/// [`VcValueTrait`]).
375///
376/// Methods should be annotated with the [`#[turbo_tasks::function]`][function] macro.
377///
378/// ```ignore
379/// #[turbo_tasks::value_impl]
380/// impl MyTrait for MyValue {
381///     #[turbo_tasks::function]
382///     fn method(&self, a: i32) -> Vc<Something> {
383///         todo!()
384///     }
385/// }
386/// ```
387#[rustfmt::skip]
388pub use turbo_tasks_macros::value_impl;
389
390/// Derives the TaskStorage struct and generates optimized storage structures.
391///
392/// This macro analyzes `field` annotations and generates:
393/// 1. A unified TaskStorage struct
394/// 2. LazyField enum for lazy_vec fields
395/// 3. Typed accessor methods on TaskStorage
396/// 4. TaskStorageAccessors trait with accessor methods
397/// 5. TaskFlags bitfield for boolean flags
398///
399/// # Field Attributes
400///
401/// All fields require two attributes:
402///
403/// ## `storage = "..."` (required)
404///
405/// Specifies how the field is stored:
406/// - `direct` - Direct field access (e.g., `Option<OutputValue>`)
407/// - `auto_set` - Uses AutoSet for small collections
408/// - `auto_map` - Uses AutoMap for key-value pairs
409/// - `counter_map` - Uses CounterMap for reference counting
410/// - `flag` - Boolean flag stored in a compact TaskFlags bitfield (field type must be `bool`)
411///
412/// ## `category = "..."` (required)
413///
414/// Specifies the data category for persistence and access:
415/// - `data` - Frequently changed, bulk I/O
416/// - `meta` - Rarely changed, small I/O
417/// - `transient` - Field is not serialized (in-memory only)
418///
419/// ## Optional Modifiers
420///
421/// - `inline` - Field is stored inline on TaskStorage (default is lazy). Only use for hot-path
422///   fields that are frequently accessed.
423/// - `default` - Use `Default::default()` semantics instead of `Option` for inline direct fields.
424/// - `filter_transient` - Filter out transient values during serialization.
425/// - Serialization methods
426#[rustfmt::skip]
427pub use turbo_tasks_macros::task_storage;
428
429pub type TaskIdSet = AutoSet<TaskId, BuildHasherDefault<FxHasher>, 2>;
turbo_tasks/lib.rs

turbo_tasks/
lib.rs
