Put timer module behind Cargo feature

.github/workflows/ci.yml

@@ -35,19 +35,20 @@ jobs:
           rustc --version
           cargo --version
 
-      # Build main crate
-      - name: Build
-        run: cargo build
-      - name: Build (all features)
-        if: ${{ matrix.toolchain == 'nightly' }}
-        run: cargo build --all-features
+      # Check crate
+      - name: Check
+        run: cargo check
+      - name: Check (no default features)
+        run: cargo check --no-default-features
+      - name: Check (all features)
+        run: cargo check --all-features
 
-      # Test main crate
+      # Test crate
       - name: Test
-        if: ${{ matrix.toolchain != 'nightly' }} 
         run: cargo test
+      - name: Test (no default features)
+        run: cargo test --no-default-features
       - name: Test (all features)
-        if: ${{ matrix.toolchain == 'nightly' }}
         run: cargo test --all-features
 
   # Check code formatting

Cargo.toml

@@ -21,6 +21,10 @@ edition = "2021"
 
 [dependencies]
 embedded-hal = { version = "0.2.7", features = ["unproven"] }
-embedded-time = "0.12"
-void = "^1.0"
+embedded-time = { version = "0.12", optional = true }
+void = { version = "^1.0", optional = true }
 nb = "0.1.1"
+
+[features]
+default = ["embedded-time"]
+embedded-time = ["dep:embedded-time", "dep:void"]

README.md

@@ -32,7 +32,7 @@ This crate requires Rust 1.56+!
 - [ ] RNG
 - [x] I/O pins (including PWM)
 - [x] ADC
-- [x] Timers
+- [x] Timers (with `embedded-time` Cargo feature)
 - [ ] ...
 
 Pull requests for more mock implementations are welcome! :)

src/lib.rs

@@ -10,6 +10,12 @@
 //!
 //! See module-level docs for more information.
 //!
+//! ## Cargo Features
+//!
+//! There are currently the following cargo features:
+//!
+//! - `embedded-time`: Enable the `timer` module (enabled by default)
+//!
 //! ## no\_std
 //!
 //! Currently this crate is not `no_std`. If you think this is important, let
@@ -27,4 +33,5 @@ pub mod i2c;
 pub mod pin;
 pub mod serial;
 pub mod spi;
+#[cfg(feature = "embedded-time")]
 pub mod timer;