Fix non-default feature build: Feature gate unpack_ffmpeg with `dow…

…nload_ffmpeg` (#56)

* Feature gate `unpack_ffmpeg` with `download_ffmpeg`
* add cargo check without default features to ci

.github/workflows/mac.yml

@@ -19,6 +19,8 @@ jobs:
       - uses: FedericoCarboni/setup-ffmpeg@v3
       - name: Build
         run: cargo build --verbose
+      - name: Check without default features
+        run: cargo check --no-default-features
       - name: Run tests
         run: cargo test --all-targets --all-features --verbose
       - name: Try auto-download

.github/workflows/ubuntu.yml

@@ -19,6 +19,8 @@ jobs:
       - uses: FedericoCarboni/setup-ffmpeg@v3
       - name: Build
         run: cargo build --verbose
+      - name: Check without default features
+        run: cargo check --no-default-features
       - name: Run tests
         run: cargo test --all-targets --all-features --verbose
       - name: Try auto-download

src/download.rs

@@ -171,6 +171,7 @@ pub fn download_ffmpeg_package(url: &str, download_dir: &Path) -> anyhow::Result
 
 /// After downloading, unpacks the archive to a folder, moves the binaries to
 /// their final location, and deletes the archive and temporary folder.
+#[cfg(feature = "download_ffmpeg")]
 pub fn unpack_ffmpeg(from_archive: &PathBuf, binary_folder: &Path) -> anyhow::Result<()> {
   let temp_dirname = UNPACK_DIRNAME;
   let temp_folder = binary_folder.join(temp_dirname);