1#![cfg(feature = "registry")]
2
3use std::sync::{Arc, Mutex};
4use tracing::{subscriber::with_default, Event, Metadata, Subscriber};
5use tracing_subscriber::{layer::Context, prelude::*, registry, Layer};
6
7struct TrackingLayer {
8 enabled: bool,
9 event_enabled_count: Arc<Mutex<usize>>,
10 event_enabled: bool,
11 on_event_count: Arc<Mutex<usize>>,
12}
13
14impl<C> Layer<C> for TrackingLayer
15where
16 C: Subscriber + Send + Sync + 'static,
17{
18 fn enabled(&self, _metadata: &Metadata<'_>, _ctx: Context<'_, C>) -> bool {
19 self.enabled
20 }
21
22 fn event_enabled(&self, _event: &Event<'_>, _ctx: Context<'_, C>) -> bool {
23 *self.event_enabled_count.lock().unwrap() += 1;
24 self.event_enabled
25 }
26
27 fn on_event(&self, _event: &Event<'_>, _ctx: Context<'_, C>) {
28 *self.on_event_count.lock().unwrap() += 1;
29 }
30}
31
32#[test]
33fn event_enabled_is_only_called_once() {
34 let event_enabled_count = Arc::new(Mutex::default());
35 let count = event_enabled_count.clone();
36 let subscriber = registry().with(TrackingLayer {
37 enabled: true,
38 event_enabled_count,
39 event_enabled: true,
40 on_event_count: Arc::new(Mutex::default()),
41 });
42 with_default(subscriber, || {
43 tracing::error!("hiya!");
44 });
45
46 assert_eq!(1, *count.lock().unwrap());
47}
48
49#[test]
50fn event_enabled_not_called_when_not_enabled() {
51 let event_enabled_count = Arc::new(Mutex::default());
52 let count = event_enabled_count.clone();
53 let subscriber = registry().with(TrackingLayer {
54 enabled: false,
55 event_enabled_count,
56 event_enabled: true,
57 on_event_count: Arc::new(Mutex::default()),
58 });
59 with_default(subscriber, || {
60 tracing::error!("hiya!");
61 });
62
63 assert_eq!(0, *count.lock().unwrap());
64}
65
66#[test]
67fn event_disabled_does_disable_event() {
68 let on_event_count = Arc::new(Mutex::default());
69 let count = on_event_count.clone();
70 let subscriber = registry().with(TrackingLayer {
71 enabled: true,
72 event_enabled_count: Arc::new(Mutex::default()),
73 event_enabled: false,
74 on_event_count,
75 });
76 with_default(subscriber, || {
77 tracing::error!("hiya!");
78 });
79
80 assert_eq!(0, *count.lock().unwrap());
81}
82