Add support for macos-14-arm64

.github/workflows/ci.yml

@@ -10,11 +10,13 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [ubuntu-latest, windows-latest, macos-13]
+        os: [ubuntu-latest, windows-latest, macos-13, macos-latest]
         link: [static, dynamic]
         exclude:
           - os: macos-13
             link: static
+          - os: macos-latest
+            link: static
 
     steps:
       - uses: actions/checkout@v4
@@ -57,11 +59,17 @@ jobs:
           cmake ..
           make -j4
 
-      - name: Install LightGBM (macos - dynamic)
+      - name: Install LightGBM (macos-13 - dynamic)
         if: matrix.os == 'macos-13' && matrix.link == 'dynamic'
         run: |
           brew install lightgbm
 
+      - name: Install LightGBM (macos - dynamic)
+        if: matrix.os == 'macos-latest' && matrix.link == 'dynamic'
+        run: |
+          brew install lightgbm
+          echo "LIGHTGBM_LIB_DIR=/opt/homebrew/Cellar/lightgbm/4.3.0/lib/" >> $GITHUB_ENV
+
       - name: Rustup update stable
         run: rustup update stable
       - name: Show cargo version

README.md

@@ -15,10 +15,12 @@ Unofficial Rust bindings for [LightGBM](https://lightgbm.readthedocs.io/en/lates
 
 ### MacOS
 
-Run the following command to install LightGBM on your system.
+1. Run `brew install lightgbm` and install LightGBM on your system.
+2. Set the environment variable `LIGHTGBM_LIB_PATH` to the directory containing `lib_lightgbm.dylib`.
 
 ```sh
 brew install lightgbm
+export LIGHTGBM_LIB_PATH=/opt/homebrew/Cellar/lightgbm/4.3.0/lib/
 ```
 
 ## Example

lgbm-sys/build.rs

@@ -50,13 +50,20 @@ fn build_linux() {
     }
 }
 fn build_macos() {
+    if let Some(dir) = try_env_var("LIGHTGBM_LIB_DIR") {
+        println!("cargo:rustc-link-search={dir}");
+    }
     println!("cargo:rustc-link-lib=dylib=_lightgbm");
 }
 
 fn env_var(key: &str) -> String {
+    try_env_var(key).unwrap_or_else(|| panic!("environment variable `{key}` is not set"))
+}
+fn try_env_var(key: &str) -> Option<String> {
     println!("cargo:rerun-if-env-changed={key}");
-    env::var(key).unwrap_or_else(|_| panic!("environment variable `{key}` is not set"))
+    env::var(key).ok()
 }
+
 fn rerun_if_changed(path: &Path) {
     println!("cargo:rerun-if-changed={}", path.display());
 }