1 files changed, 69 insertions, 0 deletions
diff --git a/tests/multiple_max_level_hints.rs b/tests/multiple_max_level_hints.rs
new file mode 100644
index 0000000..dd50a19
--- /dev/null
+++ b/tests/multiple_max_level_hints.rs
@@ -0,0 +1,69 @@
+#![cfg(feature = "std")]
+
+use tracing::Level;
+use tracing_mock::*;
+
+#[cfg_attr(target_arch = "wasm32", wasm_bindgen_test::wasm_bindgen_test)]
+#[test]
+fn multiple_max_level_hints() {
+    // This test ensures that when multiple subscribers are active, their max
+    // level hints are handled correctly. The global max level should be the
+    // maximum of the level filters returned by the two `Subscriber`'s
+    // `max_level_hint` method.
+    //
+    // In this test, we create a subscriber whose max level is `INFO`, and
+    // another whose max level is `DEBUG`. We then add an assertion to both of
+    // those subscribers' `enabled` method that no metadata for `TRACE` spans or
+    // events are filtered, since they are disabled by the global max filter.
+
+    fn do_events() {
+        tracing::info!("doing a thing that you might care about");
+        tracing::debug!("charging turboencabulator with interocitor");
+        tracing::warn!("extremely serious warning, pay attention");
+        tracing::trace!("interocitor charge level is 10%");
+        tracing::error!("everything is on fire");
+    }
+
+    let (subscriber1, handle1) = subscriber::mock()
+        .named("subscriber1")
+        .with_max_level_hint(Level::INFO)
+        .with_filter(|meta| {
+            let level = dbg!(meta.level());
+            assert!(
+                level <= &Level::DEBUG,
+                "a TRACE event was dynamically filtered by subscriber1"
+            );
+            level <= &Level::INFO
+        })
+        .event(event::mock().at_level(Level::INFO))
+        .event(event::mock().at_level(Level::WARN))
+        .event(event::mock().at_level(Level::ERROR))
+        .done()
+        .run_with_handle();
+    let (subscriber2, handle2) = subscriber::mock()
+        .named("subscriber2")
+        .with_max_level_hint(Level::DEBUG)
+        .with_filter(|meta| {
+            let level = dbg!(meta.level());
+            assert!(
+                level <= &Level::DEBUG,
+                "a TRACE event was dynamically filtered by subscriber2"
+            );
+            level <= &Level::DEBUG
+        })
+        .event(event::mock().at_level(Level::INFO))
+        .event(event::mock().at_level(Level::DEBUG))
+        .event(event::mock().at_level(Level::WARN))
+        .event(event::mock().at_level(Level::ERROR))
+        .done()
+        .run_with_handle();
+
+    let dispatch1 = tracing::Dispatch::new(subscriber1);
+
+    tracing::dispatcher::with_default(&dispatch1, do_events);
+    handle1.assert_finished();
+
+    let dispatch2 = tracing::Dispatch::new(subscriber2);
+    tracing::dispatcher::with_default(&dispatch2, do_events);
+    handle2.assert_finished();
+}