Set all crates to 2021 edition

.github/workflows/main.yml

@@ -61,7 +61,11 @@ jobs:
         rustup update stable --no-self-update
         rustup default stable
         rustup component add rustfmt
+      # log repo does not use Cargo workspaces, so `cargo fmt` will not check all the code
+      # perhaps this should be changed in the future
     - run: cargo fmt -- --check
+    - run: cargo fmt --manifest-path test_max_level_features/Cargo.toml -- --check
+    - run: cargo fmt --manifest-path tests/Cargo.toml -- --check
 
   clippy:
     name: Clippy
@@ -74,6 +78,8 @@ jobs:
         rustup default stable
         rustup component add clippy
     - run: cargo clippy --verbose
+    - run: cargo clippy --verbose --manifest-path test_max_level_features/Cargo.toml
+    - run: cargo clippy --verbose --manifest-path tests/Cargo.toml
 
   doc:
     name: Check Documentation

Cargo.toml

@@ -14,6 +14,7 @@ categories = ["development-tools::debugging"]
 keywords = ["logging"]
 exclude = ["rfcs/**/*"]
 rust-version = "1.60.0"
+edition = "2021"
 
 [package.metadata.docs.rs]
 features = ["std", "serde", "kv_unstable_std", "kv_unstable_sval", "kv_unstable_serde"]

benches/value.rs

@@ -1,9 +1,6 @@
 #![cfg(feature = "kv_unstable")]
 #![feature(test)]
 
-extern crate log;
-extern crate test;
-
 use log::kv::Value;
 
 #[bench]

rfcs/0296-structured-logging.md

@@ -1203,7 +1203,7 @@ Some useful adapters exist as provided methods on the `Source` trait. They're si
 
 - `by_ref` to get a reference to a `Source` within a method chain.
 - `chain` to concatenate one source with another. This is useful for composing implementations of `Log` together for contextual logging.
-- `get` to try find the value associated with a key. This is useful for well-defined key-value pairs that a framework built over `log` might want to provide, like timestamps or message templates.
+- `get` to try finding the value associated with a key. This is useful for well-defined key-value pairs that a framework built over `log` might want to provide, like timestamps or message templates.
 - `for_each` to execute some closure over all key-value pairs. This is a convenient way to do something with each key-value pair without having to create and implement a `Visitor`. One potential downside of `for_each` is the `Result` return value, which seems surprising when the closure itself can't fail. The `Source::for_each` call might itself fail if the underlying `visit` call fails when iterating over its key-value pairs. This shouldn't be common though, so when paired with `try_for_each`, it might be reasonable to make `for_each` return a `()` and rely on `try_for_each` for surfacing any fallibility.
 - `try_for_each` is like `for_each`, but takes a fallible closure.
 - `as_map` to get a serializable map. This is a convenient way to serialize key-value pairs without having to create and implement a `Visitor`.

src/kv/key.rs

@@ -103,11 +103,8 @@ mod std_support {
 mod sval_support {
     use super::*;
 
-    extern crate sval;
-    extern crate sval_ref;
-
-    use self::sval::Value;
-    use self::sval_ref::ValueRef;
+    use sval::Value;
+    use sval_ref::ValueRef;
 
     impl<'a> Value for Key<'a> {
         fn stream<'sval, S: sval::Stream<'sval> + ?Sized>(
@@ -119,10 +116,7 @@ mod sval_support {
     }
 
     impl<'a> ValueRef<'a> for Key<'a> {
-        fn stream_ref<S: self::sval::Stream<'a> + ?Sized>(
-            &self,
-            stream: &mut S,
-        ) -> self::sval::Result {
+        fn stream_ref<S: sval::Stream<'a> + ?Sized>(&self, stream: &mut S) -> sval::Result {
             self.key.stream(stream)
         }
     }
@@ -132,9 +126,7 @@ mod sval_support {
 mod serde_support {
     use super::*;
 
-    extern crate serde;
-
-    use self::serde::{Serialize, Serializer};
+    use serde::{Serialize, Serializer};
 
     impl<'a> Serialize for Key<'a> {
         fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>