Vendor dependencies for 0.3.0 release

vendor/tracing-subscriber/tests/duplicate_spans.rs

@@ -0,0 +1,47 @@
+#![cfg(all(feature = "env-filter", feature = "fmt"))]
+use tracing::{self, subscriber::with_default, Span};
+use tracing_subscriber::{filter::EnvFilter, FmtSubscriber};
+
+#[test]
+fn duplicate_spans() {
+    let subscriber = FmtSubscriber::builder()
+        .with_env_filter(EnvFilter::new("[root]=debug"))
+        .finish();
+
+    with_default(subscriber, || {
+        let root = tracing::debug_span!("root");
+        root.in_scope(|| {
+            // root:
+            assert_eq!(root, Span::current(), "Current span must be 'root'");
+            let leaf = tracing::debug_span!("leaf");
+            leaf.in_scope(|| {
+                // root:leaf:
+                assert_eq!(leaf, Span::current(), "Current span must be 'leaf'");
+                root.in_scope(|| {
+                    // root:leaf:
+                    assert_eq!(
+                        leaf,
+                        Span::current(),
+                        "Current span must be 'leaf' after entering twice the 'root' span"
+                    );
+                })
+            });
+            // root:
+            assert_eq!(
+                root,
+                Span::current(),
+                "Current span must be root ('leaf' exited, nested 'root' exited)"
+            );
+
+            root.in_scope(|| {
+                assert_eq!(root, Span::current(), "Current span must be root");
+            });
+            // root:
+            assert_eq!(
+                root,
+                Span::current(),
+                "Current span must still be root after exiting nested 'root'"
+            );
+        });
+    });
+}