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Diffstat (limited to 'vendor/tracing-subscriber/src/registry/sharded.rs')
| -rw-r--r-- | vendor/tracing-subscriber/src/registry/sharded.rs | 901 |
1 files changed, 0 insertions, 901 deletions
diff --git a/vendor/tracing-subscriber/src/registry/sharded.rs b/vendor/tracing-subscriber/src/registry/sharded.rs deleted file mode 100644 index b81d5fef8..000000000 --- a/vendor/tracing-subscriber/src/registry/sharded.rs +++ /dev/null @@ -1,901 +0,0 @@ -use sharded_slab::{pool::Ref, Clear, Pool}; -use thread_local::ThreadLocal; - -use super::stack::SpanStack; -use crate::{ - filter::{FilterId, FilterMap, FilterState}, - registry::{ - extensions::{Extensions, ExtensionsInner, ExtensionsMut}, - LookupSpan, SpanData, - }, - sync::RwLock, -}; -use std::{ - cell::{self, Cell, RefCell}, - sync::atomic::{fence, AtomicUsize, Ordering}, -}; -use tracing_core::{ - dispatcher::{self, Dispatch}, - span::{self, Current, Id}, - Event, Interest, Metadata, Subscriber, -}; - -/// A shared, reusable store for spans. -/// -/// A `Registry` is a [`Subscriber`] around which multiple [`Layer`]s -/// implementing various behaviors may be [added]. Unlike other types -/// implementing `Subscriber`, `Registry` does not actually record traces itself: -/// instead, it collects and stores span data that is exposed to any [`Layer`]s -/// wrapping it through implementations of the [`LookupSpan`] trait. -/// The `Registry` is responsible for storing span metadata, recording -/// relationships between spans, and tracking which spans are active and which -/// are closed. In addition, it provides a mechanism for [`Layer`]s to store -/// user-defined per-span data, called [extensions], in the registry. This -/// allows [`Layer`]-specific data to benefit from the `Registry`'s -/// high-performance concurrent storage. -/// -/// This registry is implemented using a [lock-free sharded slab][slab], and is -/// highly optimized for concurrent access. -/// -/// # Span ID Generation -/// -/// Span IDs are not globally unique, but the registry ensures that -/// no two currently active spans have the same ID within a process. -/// -/// One of the primary responsibilities of the registry is to generate [span -/// IDs]. Therefore, it's important for other code that interacts with the -/// registry, such as [`Layer`]s, to understand the guarantees of the -/// span IDs that are generated. -/// -/// The registry's span IDs are guaranteed to be unique **at a given point -/// in time**. This means that an active span will never be assigned the -/// same ID as another **currently active** span. However, the registry -/// **will** eventually reuse the IDs of [closed] spans, although an ID -/// will never be reassigned immediately after a span has closed. -/// -/// Spans are not [considered closed] by the `Registry` until *every* -/// [`Span`] reference with that ID has been dropped. -/// -/// Thus: span IDs generated by the registry should be considered unique -/// only at a given point in time, and only relative to other spans -/// generated by the same process. Two spans with the same ID will not exist -/// in the same process concurrently. However, if historical span data is -/// being stored, the same ID may occur for multiple spans times in that -/// data. If spans must be uniquely identified in historical data, the user -/// code storing this data must assign its own unique identifiers to those -/// spans. A counter is generally sufficient for this. -/// -/// Similarly, span IDs generated by the registry are not unique outside of -/// a given process. Distributed tracing systems may require identifiers -/// that are unique across multiple processes on multiple machines (for -/// example, [OpenTelemetry's `SpanId`s and `TraceId`s][ot]). `tracing` span -/// IDs generated by the registry should **not** be used for this purpose. -/// Instead, code which integrates with a distributed tracing system should -/// generate and propagate its own IDs according to the rules specified by -/// the distributed tracing system. These IDs can be associated with -/// `tracing` spans using [fields] and/or [stored span data]. -/// -/// [span IDs]: tracing_core::span::Id -/// [slab]: sharded_slab -/// [`Layer`]: crate::Layer -/// [added]: crate::layer::Layer#composing-layers -/// [extensions]: super::Extensions -/// [closed]: https://docs.rs/tracing/latest/tracing/span/index.html#closing-spans -/// [considered closed]: tracing_core::subscriber::Subscriber::try_close() -/// [`Span`]: https://docs.rs/tracing/latest/tracing/span/struct.Span.html -/// [ot]: https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/trace/api.md#spancontext -/// [fields]: tracing_core::field -/// [stored span data]: crate::registry::SpanData::extensions_mut -#[cfg(feature = "registry")] -#[cfg_attr(docsrs, doc(cfg(all(feature = "registry", feature = "std"))))] -#[derive(Debug)] -pub struct Registry { - spans: Pool<DataInner>, - current_spans: ThreadLocal<RefCell<SpanStack>>, - next_filter_id: u8, -} - -/// Span data stored in a [`Registry`]. -/// -/// The registry stores well-known data defined by tracing: span relationships, -/// metadata and reference counts. Additional user-defined data provided by -/// [`Layer`s], such as formatted fields, metrics, or distributed traces should -/// be stored in the [extensions] typemap. -/// -/// [`Layer`s]: crate::layer::Layer -/// [extensions]: Extensions -#[cfg(feature = "registry")] -#[cfg_attr(docsrs, doc(cfg(all(feature = "registry", feature = "std"))))] -#[derive(Debug)] -pub struct Data<'a> { - /// Immutable reference to the pooled `DataInner` entry. - inner: Ref<'a, DataInner>, -} - -/// Stored data associated with a span. -/// -/// This type is pooled using [`sharded_slab::Pool`]; when a span is -/// dropped, the `DataInner` entry at that span's slab index is cleared -/// in place and reused by a future span. Thus, the `Default` and -/// [`sharded_slab::Clear`] implementations for this type are -/// load-bearing. -#[derive(Debug)] -struct DataInner { - filter_map: FilterMap, - metadata: &'static Metadata<'static>, - parent: Option<Id>, - ref_count: AtomicUsize, - // The span's `Extensions` typemap. Allocations for the `HashMap` backing - // this are pooled and reused in place. - pub(crate) extensions: RwLock<ExtensionsInner>, -} - -// === impl Registry === - -impl Default for Registry { - fn default() -> Self { - Self { - spans: Pool::new(), - current_spans: ThreadLocal::new(), - next_filter_id: 0, - } - } -} - -#[inline] -fn idx_to_id(idx: usize) -> Id { - Id::from_u64(idx as u64 + 1) -} - -#[inline] -fn id_to_idx(id: &Id) -> usize { - id.into_u64() as usize - 1 -} - -/// A guard that tracks how many [`Registry`]-backed `Layer`s have -/// processed an `on_close` event. -/// -/// This is needed to enable a [`Registry`]-backed Layer to access span -/// data after the `Layer` has recieved the `on_close` callback. -/// -/// Once all `Layer`s have processed this event, the [`Registry`] knows -/// that is able to safely remove the span tracked by `id`. `CloseGuard` -/// accomplishes this through a two-step process: -/// 1. Whenever a [`Registry`]-backed `Layer::on_close` method is -/// called, `Registry::start_close` is closed. -/// `Registry::start_close` increments a thread-local `CLOSE_COUNT` -/// by 1 and returns a `CloseGuard`. -/// 2. The `CloseGuard` is dropped at the end of `Layer::on_close`. On -/// drop, `CloseGuard` checks thread-local `CLOSE_COUNT`. If -/// `CLOSE_COUNT` is 0, the `CloseGuard` removes the span with the -/// `id` from the registry, as all `Layers` that might have seen the -/// `on_close` notification have processed it. If `CLOSE_COUNT` is -/// greater than 0, `CloseGuard` decrements the counter by one and -/// _does not_ remove the span from the [`Registry`]. -/// -pub(crate) struct CloseGuard<'a> { - id: Id, - registry: &'a Registry, - is_closing: bool, -} - -impl Registry { - fn get(&self, id: &Id) -> Option<Ref<'_, DataInner>> { - self.spans.get(id_to_idx(id)) - } - - /// Returns a guard which tracks how many `Layer`s have - /// processed an `on_close` notification via the `CLOSE_COUNT` thread-local. - /// For additional details, see [`CloseGuard`]. - /// - pub(crate) fn start_close(&self, id: Id) -> CloseGuard<'_> { - CLOSE_COUNT.with(|count| { - let c = count.get(); - count.set(c + 1); - }); - CloseGuard { - id, - registry: self, - is_closing: false, - } - } - - pub(crate) fn has_per_layer_filters(&self) -> bool { - self.next_filter_id > 0 - } - - pub(crate) fn span_stack(&self) -> cell::Ref<'_, SpanStack> { - self.current_spans.get_or_default().borrow() - } -} - -thread_local! { - /// `CLOSE_COUNT` is the thread-local counter used by `CloseGuard` to - /// track how many layers have processed the close. - /// For additional details, see [`CloseGuard`]. - /// - static CLOSE_COUNT: Cell<usize> = Cell::new(0); -} - -impl Subscriber for Registry { - fn register_callsite(&self, _: &'static Metadata<'static>) -> Interest { - if self.has_per_layer_filters() { - return FilterState::take_interest().unwrap_or_else(Interest::always); - } - - Interest::always() - } - - fn enabled(&self, _: &Metadata<'_>) -> bool { - if self.has_per_layer_filters() { - return FilterState::event_enabled(); - } - true - } - - #[inline] - fn new_span(&self, attrs: &span::Attributes<'_>) -> span::Id { - let parent = if attrs.is_root() { - None - } else if attrs.is_contextual() { - self.current_span().id().map(|id| self.clone_span(id)) - } else { - attrs.parent().map(|id| self.clone_span(id)) - }; - - let id = self - .spans - // Check out a `DataInner` entry from the pool for the new span. If - // there are free entries already allocated in the pool, this will - // preferentially reuse one; otherwise, a new `DataInner` is - // allocated and added to the pool. - .create_with(|data| { - data.metadata = attrs.metadata(); - data.parent = parent; - data.filter_map = crate::filter::FILTERING.with(|filtering| filtering.filter_map()); - #[cfg(debug_assertions)] - { - if data.filter_map != FilterMap::default() { - debug_assert!(self.has_per_layer_filters()); - } - } - - let refs = data.ref_count.get_mut(); - debug_assert_eq!(*refs, 0); - *refs = 1; - }) - .expect("Unable to allocate another span"); - idx_to_id(id) - } - - /// This is intentionally not implemented, as recording fields - /// on a span is the responsibility of layers atop of this registry. - #[inline] - fn record(&self, _: &span::Id, _: &span::Record<'_>) {} - - fn record_follows_from(&self, _span: &span::Id, _follows: &span::Id) {} - - /// This is intentionally not implemented, as recording events - /// is the responsibility of layers atop of this registry. - fn event(&self, _: &Event<'_>) {} - - fn enter(&self, id: &span::Id) { - if self - .current_spans - .get_or_default() - .borrow_mut() - .push(id.clone()) - { - self.clone_span(id); - } - } - - fn exit(&self, id: &span::Id) { - if let Some(spans) = self.current_spans.get() { - if spans.borrow_mut().pop(id) { - dispatcher::get_default(|dispatch| dispatch.try_close(id.clone())); - } - } - } - - fn clone_span(&self, id: &span::Id) -> span::Id { - let span = self - .get(id) - .unwrap_or_else(|| panic!( - "tried to clone {:?}, but no span exists with that ID\n\ - This may be caused by consuming a parent span (`parent: span`) rather than borrowing it (`parent: &span`).", - id, - )); - // Like `std::sync::Arc`, adds to the ref count (on clone) don't require - // a strong ordering; if we call` clone_span`, the reference count must - // always at least 1. The only synchronization necessary is between - // calls to `try_close`: we have to ensure that all threads have - // dropped their refs to the span before the span is closed. - let refs = span.ref_count.fetch_add(1, Ordering::Relaxed); - assert_ne!( - refs, 0, - "tried to clone a span ({:?}) that already closed", - id - ); - id.clone() - } - - fn current_span(&self) -> Current { - self.current_spans - .get() - .and_then(|spans| { - let spans = spans.borrow(); - let id = spans.current()?; - let span = self.get(id)?; - Some(Current::new(id.clone(), span.metadata)) - }) - .unwrap_or_else(Current::none) - } - - /// Decrements the reference count of the span with the given `id`, and - /// removes the span if it is zero. - /// - /// The allocated span slot will be reused when a new span is created. - fn try_close(&self, id: span::Id) -> bool { - let span = match self.get(&id) { - Some(span) => span, - None if std::thread::panicking() => return false, - None => panic!("tried to drop a ref to {:?}, but no such span exists!", id), - }; - - let refs = span.ref_count.fetch_sub(1, Ordering::Release); - if !std::thread::panicking() { - assert!(refs < std::usize::MAX, "reference count overflow!"); - } - if refs > 1 { - return false; - } - - // Synchronize if we are actually removing the span (stolen - // from std::Arc); this ensures that all other `try_close` calls on - // other threads happen-before we actually remove the span. - fence(Ordering::Acquire); - true - } -} - -impl<'a> LookupSpan<'a> for Registry { - type Data = Data<'a>; - - fn span_data(&'a self, id: &Id) -> Option<Self::Data> { - let inner = self.get(id)?; - Some(Data { inner }) - } - - fn register_filter(&mut self) -> FilterId { - let id = FilterId::new(self.next_filter_id); - self.next_filter_id += 1; - id - } -} - -// === impl CloseGuard === - -impl<'a> CloseGuard<'a> { - pub(crate) fn set_closing(&mut self) { - self.is_closing = true; - } -} - -impl<'a> Drop for CloseGuard<'a> { - fn drop(&mut self) { - // If this returns with an error, we are already panicking. At - // this point, there's nothing we can really do to recover - // except by avoiding a double-panic. - let _ = CLOSE_COUNT.try_with(|count| { - let c = count.get(); - // Decrement the count to indicate that _this_ guard's - // `on_close` callback has completed. - // - // Note that we *must* do this before we actually remove the span - // from the registry, since dropping the `DataInner` may trigger a - // new close, if this span is the last reference to a parent span. - count.set(c - 1); - - // If the current close count is 1, this stack frame is the last - // `on_close` call. If the span is closing, it's okay to remove the - // span. - if c == 1 && self.is_closing { - self.registry.spans.clear(id_to_idx(&self.id)); - } - }); - } -} - -// === impl Data === - -impl<'a> SpanData<'a> for Data<'a> { - fn id(&self) -> Id { - idx_to_id(self.inner.key()) - } - - fn metadata(&self) -> &'static Metadata<'static> { - (*self).inner.metadata - } - - fn parent(&self) -> Option<&Id> { - self.inner.parent.as_ref() - } - - fn extensions(&self) -> Extensions<'_> { - Extensions::new(self.inner.extensions.read().expect("Mutex poisoned")) - } - - fn extensions_mut(&self) -> ExtensionsMut<'_> { - ExtensionsMut::new(self.inner.extensions.write().expect("Mutex poisoned")) - } - - #[inline] - fn is_enabled_for(&self, filter: FilterId) -> bool { - self.inner.filter_map.is_enabled(filter) - } -} - -// === impl DataInner === - -impl Default for DataInner { - fn default() -> Self { - // Since `DataInner` owns a `&'static Callsite` pointer, we need - // something to use as the initial default value for that callsite. - // Since we can't access a `DataInner` until it has had actual span data - // inserted into it, the null metadata will never actually be accessed. - struct NullCallsite; - impl tracing_core::callsite::Callsite for NullCallsite { - fn set_interest(&self, _: Interest) { - unreachable!( - "/!\\ Tried to register the null callsite /!\\\n \ - This should never have happened and is definitely a bug. \ - A `tracing` bug report would be appreciated." - ) - } - - fn metadata(&self) -> &Metadata<'_> { - unreachable!( - "/!\\ Tried to access the null callsite's metadata /!\\\n \ - This should never have happened and is definitely a bug. \ - A `tracing` bug report would be appreciated." - ) - } - } - - static NULL_CALLSITE: NullCallsite = NullCallsite; - static NULL_METADATA: Metadata<'static> = tracing_core::metadata! { - name: "", - target: "", - level: tracing_core::Level::TRACE, - fields: &[], - callsite: &NULL_CALLSITE, - kind: tracing_core::metadata::Kind::SPAN, - }; - - Self { - filter_map: FilterMap::default(), - metadata: &NULL_METADATA, - parent: None, - ref_count: AtomicUsize::new(0), - extensions: RwLock::new(ExtensionsInner::new()), - } - } -} - -impl Clear for DataInner { - /// Clears the span's data in place, dropping the parent's reference count. - fn clear(&mut self) { - // A span is not considered closed until all of its children have closed. - // Therefore, each span's `DataInner` holds a "reference" to the parent - // span, keeping the parent span open until all its children have closed. - // When we close a span, we must then decrement the parent's ref count - // (potentially, allowing it to close, if this child is the last reference - // to that span). - // We have to actually unpack the option inside the `get_default` - // closure, since it is a `FnMut`, but testing that there _is_ a value - // here lets us avoid the thread-local access if we don't need the - // dispatcher at all. - if self.parent.is_some() { - // Note that --- because `Layered::try_close` works by calling - // `try_close` on the inner subscriber and using the return value to - // determine whether to call the `Layer`'s `on_close` callback --- - // we must call `try_close` on the entire subscriber stack, rather - // than just on the registry. If the registry called `try_close` on - // itself directly, the layers wouldn't see the close notification. - let subscriber = dispatcher::get_default(Dispatch::clone); - if let Some(parent) = self.parent.take() { - let _ = subscriber.try_close(parent); - } - } - - // Clear (but do not deallocate!) the pooled `HashMap` for the span's extensions. - self.extensions - .get_mut() - .unwrap_or_else(|l| { - // This function can be called in a `Drop` impl, such as while - // panicking, so ignore lock poisoning. - l.into_inner() - }) - .clear(); - - self.filter_map = FilterMap::default(); - } -} - -#[cfg(test)] -mod tests { - use super::*; - use crate::{layer::Context, registry::LookupSpan, Layer}; - use std::{ - collections::HashMap, - sync::{Arc, Mutex, Weak}, - }; - use tracing::{self, subscriber::with_default}; - use tracing_core::{ - dispatcher, - span::{Attributes, Id}, - Subscriber, - }; - - #[derive(Debug)] - struct DoesNothing; - impl<S: Subscriber> Layer<S> for DoesNothing {} - - struct AssertionLayer; - impl<S> Layer<S> for AssertionLayer - where - S: Subscriber + for<'a> LookupSpan<'a>, - { - fn on_close(&self, id: Id, ctx: Context<'_, S>) { - dbg!(format_args!("closing {:?}", id)); - assert!(&ctx.span(&id).is_some()); - } - } - - #[test] - fn single_layer_can_access_closed_span() { - let subscriber = AssertionLayer.with_subscriber(Registry::default()); - - with_default(subscriber, || { - let span = tracing::debug_span!("span"); - drop(span); - }); - } - - #[test] - fn multiple_layers_can_access_closed_span() { - let subscriber = AssertionLayer - .and_then(AssertionLayer) - .with_subscriber(Registry::default()); - - with_default(subscriber, || { - let span = tracing::debug_span!("span"); - drop(span); - }); - } - - struct CloseLayer { - inner: Arc<Mutex<CloseState>>, - } - - struct CloseHandle { - state: Arc<Mutex<CloseState>>, - } - - #[derive(Default)] - struct CloseState { - open: HashMap<&'static str, Weak<()>>, - closed: Vec<(&'static str, Weak<()>)>, - } - - struct SetRemoved(Arc<()>); - - impl<S> Layer<S> for CloseLayer - where - S: Subscriber + for<'a> LookupSpan<'a>, - { - fn on_new_span(&self, _: &Attributes<'_>, id: &Id, ctx: Context<'_, S>) { - let span = ctx.span(id).expect("Missing span; this is a bug"); - let mut lock = self.inner.lock().unwrap(); - let is_removed = Arc::new(()); - assert!( - lock.open - .insert(span.name(), Arc::downgrade(&is_removed)) - .is_none(), - "test layer saw multiple spans with the same name, the test is probably messed up" - ); - let mut extensions = span.extensions_mut(); - extensions.insert(SetRemoved(is_removed)); - } - - fn on_close(&self, id: Id, ctx: Context<'_, S>) { - let span = if let Some(span) = ctx.span(&id) { - span - } else { - println!( - "span {:?} did not exist in `on_close`, are we panicking?", - id - ); - return; - }; - let name = span.name(); - println!("close {} ({:?})", name, id); - if let Ok(mut lock) = self.inner.lock() { - if let Some(is_removed) = lock.open.remove(name) { - assert!(is_removed.upgrade().is_some()); - lock.closed.push((name, is_removed)); - } - } - } - } - - impl CloseLayer { - fn new() -> (Self, CloseHandle) { - let state = Arc::new(Mutex::new(CloseState::default())); - ( - Self { - inner: state.clone(), - }, - CloseHandle { state }, - ) - } - } - - impl CloseState { - fn is_open(&self, span: &str) -> bool { - self.open.contains_key(span) - } - - fn is_closed(&self, span: &str) -> bool { - self.closed.iter().any(|(name, _)| name == &span) - } - } - - impl CloseHandle { - fn assert_closed(&self, span: &str) { - let lock = self.state.lock().unwrap(); - assert!( - lock.is_closed(span), - "expected {} to be closed{}", - span, - if lock.is_open(span) { - " (it was still open)" - } else { - ", but it never existed (is there a problem with the test?)" - } - ) - } - - fn assert_open(&self, span: &str) { - let lock = self.state.lock().unwrap(); - assert!( - lock.is_open(span), - "expected {} to be open{}", - span, - if lock.is_closed(span) { - " (it was still open)" - } else { - ", but it never existed (is there a problem with the test?)" - } - ) - } - - fn assert_removed(&self, span: &str) { - let lock = self.state.lock().unwrap(); - let is_removed = match lock.closed.iter().find(|(name, _)| name == &span) { - Some((_, is_removed)) => is_removed, - None => panic!( - "expected {} to be removed from the registry, but it was not closed {}", - span, - if lock.is_closed(span) { - " (it was still open)" - } else { - ", but it never existed (is there a problem with the test?)" - } - ), - }; - assert!( - is_removed.upgrade().is_none(), - "expected {} to have been removed from the registry", - span - ) - } - - fn assert_not_removed(&self, span: &str) { - let lock = self.state.lock().unwrap(); - let is_removed = match lock.closed.iter().find(|(name, _)| name == &span) { - Some((_, is_removed)) => is_removed, - None if lock.is_open(span) => return, - None => unreachable!(), - }; - assert!( - is_removed.upgrade().is_some(), - "expected {} to have been removed from the registry", - span - ) - } - - #[allow(unused)] // may want this for future tests - fn assert_last_closed(&self, span: Option<&str>) { - let lock = self.state.lock().unwrap(); - let last = lock.closed.last().map(|(span, _)| span); - assert_eq!( - last, - span.as_ref(), - "expected {:?} to have closed last", - span - ); - } - - fn assert_closed_in_order(&self, order: impl AsRef<[&'static str]>) { - let lock = self.state.lock().unwrap(); - let order = order.as_ref(); - for (i, name) in order.iter().enumerate() { - assert_eq!( - lock.closed.get(i).map(|(span, _)| span), - Some(name), - "expected close order: {:?}, actual: {:?}", - order, - lock.closed.iter().map(|(name, _)| name).collect::<Vec<_>>() - ); - } - } - } - - #[test] - fn spans_are_removed_from_registry() { - let (close_layer, state) = CloseLayer::new(); - let subscriber = AssertionLayer - .and_then(close_layer) - .with_subscriber(Registry::default()); - - // Create a `Dispatch` (which is internally reference counted) so that - // the subscriber lives to the end of the test. Otherwise, if we just - // passed the subscriber itself to `with_default`, we could see the span - // be dropped when the subscriber itself is dropped, destroying the - // registry. - let dispatch = dispatcher::Dispatch::new(subscriber); - - dispatcher::with_default(&dispatch, || { - let span = tracing::debug_span!("span1"); - drop(span); - let span = tracing::info_span!("span2"); - drop(span); - }); - - state.assert_removed("span1"); - state.assert_removed("span2"); - - // Ensure the registry itself outlives the span. - drop(dispatch); - } - - #[test] - fn spans_are_only_closed_when_the_last_ref_drops() { - let (close_layer, state) = CloseLayer::new(); - let subscriber = AssertionLayer - .and_then(close_layer) - .with_subscriber(Registry::default()); - - // Create a `Dispatch` (which is internally reference counted) so that - // the subscriber lives to the end of the test. Otherwise, if we just - // passed the subscriber itself to `with_default`, we could see the span - // be dropped when the subscriber itself is dropped, destroying the - // registry. - let dispatch = dispatcher::Dispatch::new(subscriber); - - let span2 = dispatcher::with_default(&dispatch, || { - let span = tracing::debug_span!("span1"); - drop(span); - let span2 = tracing::info_span!("span2"); - let span2_clone = span2.clone(); - drop(span2); - span2_clone - }); - - state.assert_removed("span1"); - state.assert_not_removed("span2"); - - drop(span2); - state.assert_removed("span1"); - - // Ensure the registry itself outlives the span. - drop(dispatch); - } - - #[test] - fn span_enter_guards_are_dropped_out_of_order() { - let (close_layer, state) = CloseLayer::new(); - let subscriber = AssertionLayer - .and_then(close_layer) - .with_subscriber(Registry::default()); - - // Create a `Dispatch` (which is internally reference counted) so that - // the subscriber lives to the end of the test. Otherwise, if we just - // passed the subscriber itself to `with_default`, we could see the span - // be dropped when the subscriber itself is dropped, destroying the - // registry. - let dispatch = dispatcher::Dispatch::new(subscriber); - - dispatcher::with_default(&dispatch, || { - let span1 = tracing::debug_span!("span1"); - let span2 = tracing::info_span!("span2"); - - let enter1 = span1.enter(); - let enter2 = span2.enter(); - - drop(enter1); - drop(span1); - - state.assert_removed("span1"); - state.assert_not_removed("span2"); - - drop(enter2); - state.assert_not_removed("span2"); - - drop(span2); - state.assert_removed("span1"); - state.assert_removed("span2"); - }); - } - - #[test] - fn child_closes_parent() { - // This test asserts that if a parent span's handle is dropped before - // a child span's handle, the parent will remain open until child - // closes, and will then be closed. - - let (close_layer, state) = CloseLayer::new(); - let subscriber = close_layer.with_subscriber(Registry::default()); - - let dispatch = dispatcher::Dispatch::new(subscriber); - - dispatcher::with_default(&dispatch, || { - let span1 = tracing::info_span!("parent"); - let span2 = tracing::info_span!(parent: &span1, "child"); - - state.assert_open("parent"); - state.assert_open("child"); - - drop(span1); - state.assert_open("parent"); - state.assert_open("child"); - - drop(span2); - state.assert_closed("parent"); - state.assert_closed("child"); - }); - } - - #[test] - fn child_closes_grandparent() { - // This test asserts that, when a span is kept open by a child which - // is *itself* kept open by a child, closing the grandchild will close - // both the parent *and* the grandparent. - let (close_layer, state) = CloseLayer::new(); - let subscriber = close_layer.with_subscriber(Registry::default()); - - let dispatch = dispatcher::Dispatch::new(subscriber); - - dispatcher::with_default(&dispatch, || { - let span1 = tracing::info_span!("grandparent"); - let span2 = tracing::info_span!(parent: &span1, "parent"); - let span3 = tracing::info_span!(parent: &span2, "child"); - - state.assert_open("grandparent"); - state.assert_open("parent"); - state.assert_open("child"); - - drop(span1); - drop(span2); - state.assert_open("grandparent"); - state.assert_open("parent"); - state.assert_open("child"); - - drop(span3); - - state.assert_closed_in_order(&["child", "parent", "grandparent"]); - }); - } -} |