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https://github.com/tokio-rs/tracing.git
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240d11a7ef
Backports #1648 from `master`. Depends on #1649 ## Motivation Presently, the `tracing-subscriber` crate requires the Rust standard library and doesn't build with `#![no_std]` targets. For the most part, this is fine, as much of `tracing-subscriber` inherently depends on `std` APIs. However, `tracing-subscriber` also contains some key abstractions that are necessary for interoperability: the `Layer` and `LookupSpan` traits. Since these traits are in `tracing-subscriber`, `no-std` users cannot currently access them. Some of the other utilities in this crate, such as the field visitor combinators, may also be useful for `#![no_std]` projects. ## Solution This branch adds "std" and "alloc" feature flags to `tracing-subscriber`, for conditionally enabling `libstd` and `liballoc`, respectively. The `registry`, `fmt`, `EnvFilter`, and `reload` APIs all require libstd, and cannot be implemented without it, but the core `Layer` and `LookupSpan` traits are now available with `#![no_std]`. Fixes #999 Signed-off-by: Eliza Weisman <eliza@buoyant.io>
40 lines
976 B
Rust
40 lines
976 B
Rust
#![cfg(feature = "std")]
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mod support;
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use self::support::*;
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use tracing_subscriber::prelude::*;
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#[test]
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fn init_ext_works() {
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let (subscriber, finished) = subscriber::mock()
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.event(
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event::mock()
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.at_level(tracing::Level::INFO)
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.with_target("init_works"),
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)
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.done()
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.run_with_handle();
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let _guard = subscriber.set_default();
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tracing::info!(target: "init_works", "it worked!");
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finished.assert_finished();
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}
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#[test]
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#[cfg(feature = "fmt")]
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fn builders_are_init_ext() {
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tracing_subscriber::fmt().set_default();
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let _ = tracing_subscriber::fmt()
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.with_target(false)
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.compact()
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.try_init();
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}
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#[test]
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#[cfg(all(feature = "fmt", feature = "env-filter"))]
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fn layered_is_init_ext() {
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tracing_subscriber::registry()
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.with(tracing_subscriber::fmt::layer())
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.with(tracing_subscriber::EnvFilter::new("foo=info"))
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.set_default();
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}
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