feat: add display UI with splash screen, dashboard, and RSSI sparkline

Implement full SSD1306 OLED display support:
- Splash screen on boot (1.5s) with project name, version, board
- Dashboard showing radio state, config, counters, RSSI/SNR
- RSSI history sparkline (64-sample ring buffer, 2px-wide bars)
- DisplayOn/DisplayOff host commands routed via dedicated channel
- Pure render functions against generic DrawTarget (no hardware coupling)
- Display on/off control bypasses radio task entirely

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

vendor/mutex-trait/.cargo-checksum.json

@@ -0,0 +1 @@
+{"files":{".cargo_vcs_info.json":"57266bd9c8f86f8f8b5dfdfc6de4721e0c441fc546405a34df9851c6aab9bf26",".github/CODEOWNERS":"4c941d2793c0360c653073d3532cf1ec80d34133ecc877525b62245fc6c3f340",".github/bors.toml":"6bb84926537bf827cd53db7fb60d2b5fa09b81c2e80e3c7de59442fbbeb0999f",".travis.yml":"e6e6ea28b105d40fe6ce22a105cbca5a8728e6a095321927b7205645cde05755","CHANGELOG.md":"989eaab000aebf7b56fe1e3d158cfd480d82931d9a27f72cbb498bb329c304d4","CODE_OF_CONDUCT.md":"3746a267d008534cec6d7242f09ca6284c5d37e48306531b878461e6c4d33fee","Cargo.toml":"0f59595b6a2e6f034e8211877fd7f1185c204dc48b39d0475a2568ddd1c45286","Cargo.toml.orig":"0a70326e2a6040b1236facf8fc875c4f658afff297e0c4fbcc85d05a076a3518","LICENSE-APACHE":"a60eea817514531668d7e00765731449fe14d059d3249e0bc93b36de45f759f2","LICENSE-MIT":"0a633406531735659d570e7903394ec52f7707195a3c4af10279f06eec7acc76","README.md":"988c012445d6b29cf91baf16ca85aaf7f5f9d270d98a09987cea4b1e0e48ebf5","ci/install.sh":"818cf567e442d1afba6e446692c24de8b9005835970ab3c6e65744bb7715f9f4","ci/script.sh":"f9aab63e656731a6bbc3752654fe76f385e9178abb4b15c96461e635be288582","src/lib.rs":"eef466e78b9a4c678621ba06932096601d5d68c73dc1087a700666ccb6825616"},"package":"b4bb1638d419e12f8b1c43d9e639abd0d1424285bdea2f76aa231e233c63cd3a"}

vendor/mutex-trait/.cargo_vcs_info.json

@@ -0,0 +1,5 @@
+{
+  "git": {
+    "sha1": "753b9e71c4527e3f7b193e6c66711b2509ad37a2"
+  }
+}

vendor/mutex-trait/.github/CODEOWNERS

@@ -0,0 +1 @@
+* @rust-embedded/cortex-m

vendor/mutex-trait/.github/bors.toml

@@ -0,0 +1,4 @@
+block_labels = ["needs-decision"]
+delete_merged_branches = true
+required_approvals = 1
+status = ["continuous-integration/travis-ci/push"]

vendor/mutex-trait/.travis.yml

@@ -0,0 +1,68 @@
+language: rust
+
+matrix:
+  include:
+    - env: TARGET=x86_64-unknown-linux-gnu
+      rust: stable
+      if: (branch = staging OR branch = trying) OR (type = pull_request AND branch = master)
+
+    - env: TARGET=thumbv6m-none-eabi
+      rust: stable
+      if: (branch = staging OR branch = trying) OR (type = pull_request AND branch = master)
+
+    - env: TARGET=thumbv7m-none-eabi
+      rust: stable
+      if: (branch = staging OR branch = trying) OR (type = pull_request AND branch = master)
+
+    - env: TARGET=thumbv7em-none-eabi
+      rust: stable
+      if: (branch = staging OR branch = trying) OR (type = pull_request AND branch = master)
+
+    - env: TARGET=thumbv7em-none-eabihf
+      rust: stable
+      if: (branch = staging OR branch = trying) OR (type = pull_request AND branch = master)
+
+    # MSRV
+    - env: TARGET=thumbv6m-none-eabi
+      rust: 1.31.0
+      if: (branch = staging OR branch = trying) OR (type = pull_request AND branch = master)
+
+    # MSRV
+    - env: TARGET=thumbv7m-none-eabi
+      rust: 1.31.0
+      if: (branch = staging OR branch = trying) OR (type = pull_request AND branch = master)
+
+    # MSRV
+    - env: TARGET=thumbv7em-none-eabi
+      rust: 1.31.0
+      if: (branch = staging OR branch = trying) OR (type = pull_request AND branch = master)
+
+    # MSRV
+    - env: TARGET=thumbv7em-none-eabihf
+      rust: 1.31.0
+      if: (branch = staging OR branch = trying) OR (type = pull_request AND branch = master)
+
+before_install: set -e
+
+install:
+  - bash ci/install.sh
+
+script:
+  - bash ci/script.sh
+
+after_script: set +e
+
+cache: cargo
+
+before_cache:
+  - chmod -R a+r $HOME/.cargo;
+
+branches:
+  only:
+    - master
+    - staging
+    - trying
+
+notifications:
+  email:
+    on_success: never

vendor/mutex-trait/CHANGELOG.md

@@ -0,0 +1,21 @@
+# Change Log
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](http://keepachangelog.com/)
+and this project adheres to [Semantic Versioning](http://semver.org/).
+
+## [Unreleased]
+
+## [0.2.0]
+
+### Changes
+
+- [breaking-change] `Exclusive` was changed to be a reference wrapper to work with external resources
+
+## [0.1.0]
+
+- First release
+
+[Unreleased]: https://github.com/rust-embedded/mutex-trait/compare/v0.2.0...HEAD
+[v0.2.0]: https://github.com/rust-embedded/mutex-trait/compare/v0.1.0...v0.2.0

vendor/mutex-trait/CODE_OF_CONDUCT.md

@@ -0,0 +1,37 @@
+# The Rust Code of Conduct
+
+## Conduct
+
+**Contact**: [Cortex-M team](https://github.com/rust-embedded/wg#the-cortex-m-team)
+
+* We are committed to providing a friendly, safe and welcoming environment for all, regardless of level of experience, gender identity and expression, sexual orientation, disability, personal appearance, body size, race, ethnicity, age, religion, nationality, or other similar characteristic.
+* On IRC, please avoid using overtly sexual nicknames or other nicknames that might detract from a friendly, safe and welcoming environment for all.
+* Please be kind and courteous. There's no need to be mean or rude.
+* Respect that people have differences of opinion and that every design or implementation choice carries a trade-off and numerous costs. There is seldom a right answer.
+* Please keep unstructured critique to a minimum. If you have solid ideas you want to experiment with, make a fork and see how it works.
+* We will exclude you from interaction if you insult, demean or harass anyone. That is not welcome behavior. We interpret the term "harassment" as including the definition in the [Citizen Code of Conduct](http://citizencodeofconduct.org/); if you have any lack of clarity about what might be included in that concept, please read their definition. In particular, we don't tolerate behavior that excludes people in socially marginalized groups.
+* Private harassment is also unacceptable. No matter who you are, if you feel you have been or are being harassed or made uncomfortable by a community member, please contact one of the channel ops or any of the [Cortex-M team][team] immediately. Whether you're a regular contributor or a newcomer, we care about making this community a safe place for you and we've got your back.
+* Likewise any spamming, trolling, flaming, baiting or other attention-stealing behavior is not welcome.
+
+## Moderation
+
+These are the policies for upholding our community's standards of conduct.
+
+1. Remarks that violate the Rust standards of conduct, including hateful, hurtful, oppressive, or exclusionary remarks, are not allowed. (Cursing is allowed, but never targeting another user, and never in a hateful manner.)
+2. Remarks that moderators find inappropriate, whether listed in the code of conduct or not, are also not allowed.
+3. Moderators will first respond to such remarks with a warning.
+4. If the warning is unheeded, the user will be "kicked," i.e., kicked out of the communication channel to cool off.
+5. If the user comes back and continues to make trouble, they will be banned, i.e., indefinitely excluded.
+6. Moderators may choose at their discretion to un-ban the user if it was a first offense and they offer the offended party a genuine apology.
+7. If a moderator bans someone and you think it was unjustified, please take it up with that moderator, or with a different moderator, **in private**. Complaints about bans in-channel are not allowed.
+8. Moderators are held to a higher standard than other community members. If a moderator creates an inappropriate situation, they should expect less leeway than others.
+
+In the Rust community we strive to go the extra step to look out for each other. Don't just aim to be technically unimpeachable, try to be your best self. In particular, avoid flirting with offensive or sensitive issues, particularly if they're off-topic; this all too often leads to unnecessary fights, hurt feelings, and damaged trust; worse, it can drive people away from the community entirely.
+
+And if someone takes issue with something you said or did, resist the urge to be defensive. Just stop doing what it was they complained about and apologize. Even if you feel you were misinterpreted or unfairly accused, chances are good there was something you could've communicated better — remember that it's your responsibility to make your fellow Rustaceans comfortable. Everyone wants to get along and we are all here first and foremost because we want to talk about cool technology. You will find that people will be eager to assume good intent and forgive as long as you earn their trust.
+
+The enforcement policies listed above apply to all official embedded WG venues; including official IRC channels (#rust-embedded); GitHub repositories under rust-embedded; and all forums under rust-embedded.org (forum.rust-embedded.org).
+
+*Adapted from the [Node.js Policy on Trolling](http://blog.izs.me/post/30036893703/policy-on-trolling) as well as the [Contributor Covenant v1.3.0](https://www.contributor-covenant.org/version/1/3/0/).*
+
+[team]: https://github.com/rust-embedded/wg#the-cortex-m-team

vendor/mutex-trait/Cargo.toml

@@ -0,0 +1,24 @@
+# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
+#
+# When uploading crates to the registry Cargo will automatically
+# "normalize" Cargo.toml files for maximal compatibility
+# with all versions of Cargo and also rewrite `path` dependencies
+# to registry (e.g., crates.io) dependencies
+#
+# If you believe there's an error in this file please file an
+# issue against the rust-lang/cargo repository. If you're
+# editing this file be aware that the upstream Cargo.toml
+# will likely look very different (and much more reasonable)
+
+[package]
+edition = "2018"
+name = "mutex-trait"
+version = "0.2.0"
+authors = ["The Cortex-M Team <cortex-m@teams.rust-embedded.org>"]
+description = "Foundational mutex trait and helpers"
+documentation = "https://docs.rs/mutex-trait"
+readme = "README.md"
+keywords = ["mutex"]
+categories = ["embedded", "no-std"]
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/rust-embedded/mutex-trait"

vendor/mutex-trait/LICENSE-APACHE

@@ -0,0 +1,201 @@
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+
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vendor/mutex-trait/LICENSE-MIT

@@ -0,0 +1,25 @@
+Copyright (c) 2016 Jorge Aparicio
+
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
+publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.

vendor/mutex-trait/README.md

@@ -0,0 +1,36 @@
+[![crates.io](https://img.shields.io/crates/d/mutex-trait.svg)](https://crates.io/crates/mutex-trait)
+[![crates.io](https://img.shields.io/crates/v/mutex-trait.svg)](https://crates.io/crates/mutex-trait)
+
+# `mutex-trait`
+
+> Low level API definition of a Mutex
+
+This project is developed and maintained by the [Resources team][team].
+
+## [Documentation](https://docs.rs/mutex-trait)
+
+## License
+
+Licensed under either of
+
+- Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or
+  http://www.apache.org/licenses/LICENSE-2.0)
+- MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
+
+at your option.
+
+### Contribution
+
+Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the
+work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any
+additional terms or conditions.
+
+## Code of Conduct
+
+Contribution to this crate is organized under the terms of the [Rust Code of
+Conduct][CoC], the maintainer of this crate, the [Resources team][team], promises
+to intervene to uphold that code of conduct.
+
+[CoC]: CODE_OF_CONDUCT.md
+[team]: https://github.com/rust-embedded/wg#the-resources-team
+

vendor/mutex-trait/ci/install.sh

@@ -0,0 +1,11 @@
+set -euxo pipefail
+
+main() {
+    case $TARGET in
+        thumbv*-none-eabi*)
+            rustup target add $TARGET
+            ;;
+    esac
+}
+
+main

vendor/mutex-trait/ci/script.sh

@@ -0,0 +1,29 @@
+set -euxo pipefail
+
+main() {
+    if [ $TRAVIS_RUST_VERSION = nightly ]; then
+        export RUSTFLAGS="-D warnings"
+    fi
+
+    cargo check --target $TARGET
+
+    case $TARGET in
+        thumbv*-none-eabi*)
+            ;;
+
+        x86_64-unknown-linux-gnu)
+            cargo test --target $TARGET
+            ;;
+    esac
+
+    if [ $TRAVIS_RUST_VERSION = nightly ]; then
+        # Get the latest nightly with a working clippy
+        rustup toolchain uninstall nightly
+        rustup set profile default
+        rustup default nightly
+        rustup target add $TARGET
+        cargo clippy --target $TARGET -- -D warnings
+    fi
+}
+
+main

vendor/mutex-trait/src/lib.rs

@@ -0,0 +1,326 @@
+//! Low level definition of a Mutex.
+//!
+//! This crate provides:
+//!
+//! - A `Mutex` trait that is to be used as the foundation of exclusive access to the data
+//!   contained within it.
+//! - Helper traits and implementations which allows for multiple locks to be taken at once.
+//!
+//! RFC that added this trait: [RFC #377](https://github.com/rust-embedded/wg/blob/master/rfcs/0377-mutex-trait.md)
+//!
+//! # Example
+//!
+//! ```
+//! use mutex_trait::prelude::*;
+//!
+//! // A function taking 2 mutexes
+//! fn normal_lock(
+//!     a: &mut impl Mutex<Data = i32>,
+//!     b: &mut impl Mutex<Data = i32>,
+//! ) {
+//!     // Taking each lock separately
+//!     a.lock(|a| {
+//!         b.lock(|b| {
+//!             *a += 1;
+//!             *b += 1;
+//!         });
+//!     });
+//!
+//!     // Or both at once
+//!     (a, b).lock(|a, b| {
+//!         *a += 1;
+//!         *b += 1;
+//!     });
+//! }
+//! ```
+//!
+//! # Minimum Supported Rust Version (MSRV)
+//!
+//! This crate is guaranteed to compile on stable Rust 1.31 and up. It *might*
+//! compile with older versions but that may change in any new patch release.
+
+#![no_std]
+#![deny(missing_docs)]
+
+use core::cell::RefCell;
+use core::ops::{Deref, DerefMut};
+
+/// Makes locks work on N-tuples, locks the mutexes from left-to-right in the tuple. These are
+/// used to reduce rightward drift in code and to help make intentions clearer.
+///
+/// # Example
+///
+/// ```
+/// use mutex_trait::prelude::*;
+///
+/// fn normal_lock(
+///     a: &mut impl Mutex<Data = i32>,
+///     b: &mut impl Mutex<Data = i32>,
+///     c: &mut impl Mutex<Data = i32>
+/// ) {
+///     // A lot of rightward drift...
+///     a.lock(|a| {
+///         b.lock(|b| {
+///             c.lock(|c| {
+///                 *a += 1;
+///                 *b += 1;
+///                 *c += 1;
+///             });
+///         });
+///     });
+/// }
+/// ```
+///
+/// Has a shorthand as:
+///
+/// ```
+/// use mutex_trait::prelude::*;
+///
+/// fn tuple_lock(
+///     a: &mut impl Mutex<Data = i32>,
+///     b: &mut impl Mutex<Data = i32>,
+///     c: &mut impl Mutex<Data = i32>
+/// ) {
+///     // Look! Single indent and less to write
+///     (a, b, c).lock(|a, b, c| {
+///         *a += 1;
+///         *b += 1;
+///         *c += 1;
+///     });
+/// }
+/// ```
+pub mod prelude {
+    pub use crate::Mutex;
+
+    macro_rules! lock {
+        ($e:ident, $fun:block) => {
+            $e.lock(|$e| $fun )
+        };
+        ($e:ident, $($es:ident),+, $fun:block) => {
+            $e.lock(|$e| lock!($($es),*, $fun))
+        };
+    }
+
+    macro_rules! make_tuple_impl {
+        ($name:ident, $($es:ident),+) => {
+            /// Auto-generated tuple implementation, see [`Mutex`](../trait.Mutex.html) for details.
+            pub trait $name {
+                $(
+                    /// Data protected by the mutex.
+                    type $es;
+                )*
+
+                /// Creates a critical section and grants temporary access to the protected data.
+                fn lock<R>(&mut self, f: impl FnOnce($(&mut Self::$es),*) -> R) -> R;
+            }
+
+            impl<$($es),+> $name for ($($es,)+)
+            where
+                $($es: crate::Mutex),*
+            {
+                $(
+                    type $es = $es::Data;
+                )*
+
+                #[allow(non_snake_case)]
+                fn lock<R>(&mut self, f: impl FnOnce($(&mut Self::$es),*) -> R) -> R {
+                    let ($(
+                        $es,
+                    )*) = self;
+
+                    lock!($($es),*, { f($($es),*) })
+                }
+            }
+        };
+    }
+
+    // Generate tuple lock impls
+    make_tuple_impl!(TupleExt01, T1);
+    make_tuple_impl!(TupleExt02, T1, T2);
+    make_tuple_impl!(TupleExt03, T1, T2, T3);
+    make_tuple_impl!(TupleExt04, T1, T2, T3, T4);
+    make_tuple_impl!(TupleExt05, T1, T2, T3, T4, T5);
+    make_tuple_impl!(TupleExt06, T1, T2, T3, T4, T5, T6);
+    make_tuple_impl!(TupleExt07, T1, T2, T3, T4, T5, T6, T7);
+    make_tuple_impl!(TupleExt08, T1, T2, T3, T4, T5, T6, T7, T8);
+    make_tuple_impl!(TupleExt09, T1, T2, T3, T4, T5, T6, T7, T8, T9);
+    make_tuple_impl!(TupleExt10, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10);
+    make_tuple_impl!(TupleExt11, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11);
+    make_tuple_impl!(TupleExt12, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12);
+}
+
+/// Any object implementing this trait guarantees exclusive access to the data contained
+/// within the mutex for the duration of the lock.
+pub trait Mutex {
+    /// Data protected by the mutex.
+    type Data;
+
+    /// Creates a critical section and grants temporary access to the protected data.
+    fn lock<R>(&mut self, f: impl FnOnce(&mut Self::Data) -> R) -> R;
+}
+
+// `lock` will now work on any mutable reference to a lock
+impl<L> Mutex for &'_ mut L
+where
+    L: Mutex,
+{
+    type Data = L::Data;
+
+    fn lock<R>(&mut self, f: impl FnOnce(&mut Self::Data) -> R) -> R {
+        L::lock(self, f)
+    }
+}
+
+// A RefCell is a lock in single threaded applications
+impl<T> Mutex for &'_ RefCell<T> {
+    type Data = T;
+
+    fn lock<R>(&mut self, f: impl FnOnce(&mut T) -> R) -> R {
+        f(&mut self.borrow_mut())
+    }
+}
+
+/// Wraps a `T` and provides exclusive access via a `Mutex` impl.
+///
+/// This provides an no-op `Mutex` implementation for data that does not need a real mutex.
+#[derive(Debug)]
+pub struct Exclusive<'a, T>(&'a mut T);
+
+impl<'a, T> Exclusive<'a, T> {
+    /// Creates a new `Exclusive` object wrapping `data`.
+    pub fn new(data: &'a mut T) -> Self {
+        Exclusive(data)
+    }
+
+    /// Consumes this `Exclusive` instance and returns the wrapped value.
+    pub fn into_inner(self) -> &'a mut T {
+        self.0
+    }
+}
+
+impl<'a, T> From<&'a mut T> for Exclusive<'a, T> {
+    fn from(data: &'a mut T) -> Self {
+        Exclusive(data)
+    }
+}
+
+impl<'a, T> Deref for Exclusive<'a, T> {
+    type Target = T;
+
+    fn deref(&self) -> &T {
+        self.0
+    }
+}
+
+impl<'a, T> DerefMut for Exclusive<'a, T> {
+    fn deref_mut(&mut self) -> &mut T {
+        self.0
+    }
+}
+
+impl<'a, T> Mutex for Exclusive<'a, T> {
+    type Data = T;
+
+    fn lock<R>(&mut self, f: impl FnOnce(&mut T) -> R) -> R {
+        f(self.0)
+    }
+}
+
+#[cfg(test)]
+#[allow(dead_code)]
+mod tests {
+    use crate::prelude::*;
+    use crate::Exclusive;
+
+    fn compile_test_single_move(mut a: impl Mutex<Data = i32>) {
+        a.lock(|a| {
+            *a += 1;
+        });
+    }
+
+    fn compile_test_single_reference(a: &mut impl Mutex<Data = i32>) {
+        a.lock(|a| {
+            *a += 1;
+        });
+    }
+
+    fn compile_test_double_move(mut a: impl Mutex<Data = i32>, mut b: impl Mutex<Data = i32>) {
+        a.lock(|a| {
+            *a += 1;
+        });
+
+        b.lock(|b| {
+            *b += 1;
+        });
+
+        (a, b).lock(|a, b| {
+            *a += 1;
+            *b += 1;
+        });
+    }
+
+    fn compile_test_double_reference(
+        a: &mut impl Mutex<Data = i32>,
+        b: &mut impl Mutex<Data = i32>,
+    ) {
+        a.lock(|a| {
+            *a += 1;
+        });
+
+        b.lock(|b| {
+            *b += 1;
+        });
+
+        (a, b).lock(|a, b| {
+            *a += 1;
+            *b += 1;
+        });
+    }
+
+    fn compile_test_move_and_reference(
+        mut a: impl Mutex<Data = i32>,
+        b: &mut impl Mutex<Data = i32>,
+    ) {
+        a.lock(|a| {
+            *a += 1;
+        });
+
+        b.lock(|b| {
+            *b += 1;
+        });
+
+        (a, b).lock(|a, b| {
+            *a += 1;
+            *b += 1;
+        });
+    }
+
+    #[test]
+    fn refcell_lock() {
+        let a = core::cell::RefCell::new(0);
+        let b = core::cell::RefCell::new(0);
+
+        (&a).lock(|a| {
+            *a += 1;
+        });
+
+        (&b).lock(|b| {
+            *b += 1;
+        });
+
+        (&a, &b).lock(|a, b| {
+            *a += 1;
+            *b += 1;
+        });
+    }
+
+    #[test]
+    fn exclusive() {
+        let mut var = 0;
+        let mut excl = Exclusive(&mut var);
+
+        excl.lock(|val| *val += 1);
+
+        assert_eq!(*excl.into_inner(), 1);
+    }
+}