1 files changed, 49 insertions, 0 deletions
diff --git a/vendor/tracing-log/src/env_logger.rs b/vendor/tracing-log/src/env_logger.rs
new file mode 100644
index 000000000..74922d1dc
--- /dev/null
+++ b/vendor/tracing-log/src/env_logger.rs
@@ -0,0 +1,49 @@
+//! Utilities for configuring the `env_logger` crate to emit `tracing` events.
+
+/// Extension trait to configure an `env_logger::Builder` to emit traces.
+pub trait BuilderExt: crate::sealed::Sealed {
+    /// Configure the built `env_logger::Logger` to emit `tracing` events for
+    /// all consumed `log` records, rather than printing them to standard out.
+    ///
+    /// Note that this replaces any previously configured formatting.
+    fn emit_traces(&mut self) -> &mut Self;
+}
+
+impl crate::sealed::Sealed for env_logger::Builder {}
+
+impl BuilderExt for env_logger::Builder {
+    fn emit_traces(&mut self) -> &mut Self {
+        self.format(|_, record| super::format_trace(record))
+    }
+}
+
+/// Attempts to initialize the global logger with an env logger configured to
+/// emit `tracing` events.
+///
+/// This should be called early in the execution of a Rust program. Any log
+/// events that occur before initialization will be ignored.
+///
+/// # Errors
+///
+/// This function will fail if it is called more than once, or if another
+/// library has already initialized a global logger.
+pub fn try_init() -> Result<(), log::SetLoggerError> {
+    env_logger::Builder::from_default_env()
+        .emit_traces()
+        .try_init()
+}
+
+/// Initializes the global logger with an env logger configured to
+/// emit `tracing` events.
+///
+/// This should be called early in the execution of a Rust program. Any log
+/// events that occur before initialization will be ignored.
+///
+/// # Panics
+///
+/// This function will panic if it is called more than once, or if another
+/// library has already initialized a global logger.
+pub fn init() {
+    try_init()
+        .expect("tracing_log::env_logger::init should not be called after logger initialized");
+}