Add conditional compilation for CI

.github/workflows/rust.yml

@@ -19,35 +19,41 @@ jobs:
 #   - name: Ninja Install
 #     run: pip install ninja
     - uses: actions/checkout@v3
+    - name: Set up environment
+      run: |
+        New-Item '.cargo' -ItemType 'directory'
+        'build.rustflags = [''--cfg'', ''CI'']' | Out-File .cargo/config.toml -Encoding 'utf8'
     - name: Build tests
       run: cargo build --tests --verbose
     - name: Run tests
       run: cargo test --verbose
     - name: Build examples
-      run: |
-        cd examples
-        cargo build --bins --verbose
+      run: cargo build --bins --verbose
   linux_stable:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v3
+    - name: Set up environment
+      run: |
+        mkdir .cargo
+        echo 'build.rustflags = ["--cfg", "CI"]' > .cargo/config.toml
     - name: Build tests
       run: cargo build --tests --verbose
     - name: Run tests
       run: cargo test --verbose
     - name: Build examples
-      run: |
-        cd examples
-        cargo build --bins --verbose
+      run: cargo build --bins --verbose
   macos_stable:
     runs-on: macos-latest
     steps:
     - uses: actions/checkout@v3
+    - name: Set up environment
+      run: |
+        mkdir .cargo
+        echo 'build.rustflags = ["--cfg", "CI"]' > .cargo/config.toml
     - name: Build tests
       run: cargo build --tests --verbose
     - name: Run tests
       run: cargo test --verbose
     - name: Build examples
-      run: |
-        cd examples
-        cargo build --bins --verbose
+      run: cargo build --bins --verbose

vulkano/src/swapchain/surface.rs

@@ -61,9 +61,17 @@ pub struct Surface {
 impl Surface {
     /// Returns the instance extensions required to create a surface from a window of the given
     /// event loop.
+    #[cfg_attr(CI, allow(unreachable_code, unused))]
     pub fn required_extensions(
         event_loop: &impl HasDisplayHandle,
     ) -> Result<InstanceExtensions, HandleError> {
+        #[cfg(CI)]
+        return Ok(InstanceExtensions {
+            khr_surface: true,
+            ext_headless_surface: true,
+            ..InstanceExtensions::empty()
+        });
+
         let mut extensions = InstanceExtensions {
             khr_surface: true,
             ..InstanceExtensions::empty()
@@ -100,10 +108,14 @@ impl Surface {
     /// # Safety
     ///
     /// - The given `window` must outlive the created surface.
+    #[cfg_attr(CI, allow(unreachable_code, unused))]
     pub unsafe fn from_window_ref(
         instance: Arc<Instance>,
         window: &(impl HasWindowHandle + HasDisplayHandle),
     ) -> Result<Arc<Self>, FromWindowError> {
+        #[cfg(CI)]
+        return Self::headless(instance, None).map_err(FromWindowError::CreateSurface);
+
         let window_handle = window
             .window_handle()
             .map_err(FromWindowError::RetrieveHandle)?;