From e0f4bef69ae65fb8e16e0f7fc96cd9f3c19aab52 Mon Sep 17 00:00:00 2001 From: Chris Burgess Date: Sat, 16 Jul 2022 14:12:29 -0400 Subject: [PATCH] tracing-subscriber: correct fmt::init() documentation Previously the documentation for `fmt::init()` was misleading. It stated that it was shorthand for `fmt().init()`. This lead to confusion as users would expect the same behavior from both. However `fmt::init()` would, whether you used the env-filter feature or not, rely on RUST_LOG to set the tracing level. `fmt().init()` does not do this and it must be set with a specific configuration via `with_env_filter`. The documentation has been updated to no longer state that it is 1:1 shorthand for the other. The documentation now specifically points out that you must be using the `env-filter` feature and gives a correct example to mimic the `fmt::init()` behavior using `fmt().init()`. fixes: #2217 #1329 --- tracing-subscriber/src/fmt/mod.rs | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/tracing-subscriber/src/fmt/mod.rs b/tracing-subscriber/src/fmt/mod.rs index 3c6a6ac40e..989bc8375f 100644 --- a/tracing-subscriber/src/fmt/mod.rs +++ b/tracing-subscriber/src/fmt/mod.rs @@ -1188,10 +1188,13 @@ pub fn try_init() -> Result<(), Box> { /// If the `tracing-log` feature is enabled, this will also install /// the LogTracer to convert `Log` records into `tracing` `Event`s. /// -/// This is shorthand for +/// If the `env-filter` feature is enabled, this is shorthand for /// /// ```rust -/// tracing_subscriber::fmt().init() +/// # use tracing_subscriber::EnvFilter; +/// tracing_subscriber::fmt() +/// .with_env_filter(EnvFilter::from_default_env()) +/// .init(); /// ``` /// /// # Panics