Add static classes

.github/workflows/ci.yml

@@ -206,7 +206,10 @@ jobs:
     - name: Setup SDK environment
       if: matrix.sdk
       # This changes a variable, so is only set when a custom SDK is used
-      run: echo "SDKROOT=$HOME/extern/sdk" >> $GITHUB_ENV
+      run: |
+        echo "SDKROOT=$HOME/extern/sdk" >> $GITHUB_ENV
+        # Temporary
+        echo "RUSTFLAGS=$RUSTFLAGS --cfg=macos_10_7" >> $GITHUB_ENV
 
     - name: Install Clang & Valgrind
       if: contains(matrix.os, 'ubuntu')
@@ -395,12 +398,12 @@ jobs:
         # Not using --all-features because that would enable e.g. gnustep
         args: ${{ env.ARGS }} ${{ env.TESTARGS }} --features ${{ env.FEATURES }},${{ env.UNSTABLE_FEATURES }}
 
-    - name: Test static selectors
+    - name: Test static class and selectors
       if: ${{ !matrix.dinghy && (matrix.runtime || 'apple') == 'apple' }}
       uses: actions-rs/cargo@v1
       with:
         command: test
-        args: ${{ env.ARGS }} ${{ env.TESTARGS }} --features unstable-static-sel
+        args: ${{ env.ARGS }} ${{ env.TESTARGS }} --features unstable-static-sel,unstable-static-class
 
     - name: Run assembly tests
       if: ${{ !contains(matrix.runtime, 'compiler-rt') }}

helper-scripts/test-local.fish

@@ -34,5 +34,5 @@ rm -d .cargo
 export SDKROOT=(pwd)/ideas/MacOSX10.13.sdk
 export CARGO_BUILD_TARGET=i686-apple-darwin
 cargo +nightly test -Zbuild-std
-cargo +nightly test -Zbuild-std --features malloc,block,exception,catch-all,verify_message
+cargo +nightly test -Zbuild-std --features malloc,block,exception,catch-all,verify_message,unstable-static-class,unstable-static-sel
 cargo +nightly test -Zbuild-std --release

objc2-foundation/examples/declaration.rs

@@ -1,18 +1,22 @@
+#[cfg(all(feature = "apple", target_os = "macos"))]
 use objc2::{
     msg_send, msg_send_id,
     rc::{Id, Shared},
     runtime::{Bool, Object},
 };
+#[cfg(all(feature = "apple", target_os = "macos"))]
 use objc2_foundation::{declare_class, extern_class, NSObject};
 
 #[cfg(all(feature = "apple", target_os = "macos"))]
 #[link(name = "AppKit", kind = "framework")]
 extern "C" {}
 
+#[cfg(all(feature = "apple", target_os = "macos"))]
 extern_class! {
     unsafe struct NSResponder: NSObject;
 }
 
+#[cfg(all(feature = "apple", target_os = "macos"))]
 declare_class! {
     unsafe struct CustomAppDelegate: NSResponder, NSObject {
         pub ivar: u8,
@@ -66,6 +70,7 @@ declare_class! {
     }
 }
 
+#[cfg(all(feature = "apple", target_os = "macos"))]
 impl CustomAppDelegate {
     pub fn new(ivar: u8, another_ivar: bool) -> Id<Self, Shared> {
         let cls = Self::class();
@@ -80,9 +85,15 @@ impl CustomAppDelegate {
     }
 }
 
+#[cfg(all(feature = "apple", target_os = "macos"))]
 fn main() {
     let delegate = CustomAppDelegate::new(42, true);
 
     println!("{}", delegate.ivar);
     println!("{}", delegate.another_ivar.as_bool());
 }
+
+#[cfg(not(all(feature = "apple", target_os = "macos")))]
+fn main() {
+    panic!("This example uses AppKit, which is only present on macOS");
+}

objc2-foundation/examples/nspasteboard.rs

@@ -7,7 +7,7 @@ use std::ops::{Deref, DerefMut};
 
 use objc2::rc::{Id, Shared};
 use objc2::runtime::{Class, Object};
-use objc2::{class, msg_send, msg_send_bool, msg_send_id};
+use objc2::{msg_send, msg_send_bool, msg_send_id};
 use objc2::{Encoding, Message, RefEncode};
 
 use objc2_foundation::{NSArray, NSDictionary, NSInteger, NSObject, NSString};
@@ -59,7 +59,14 @@ impl DerefMut for NSPasteboard {
 impl NSPasteboard {
     /// Common convenience method.
     pub fn class() -> &'static Class {
-        class!(NSPasteboard)
+        #[cfg(all(feature = "apple", target_os = "macos"))]
+        {
+            objc2::class!(NSPasteboard)
+        }
+        #[cfg(not(all(feature = "apple", target_os = "macos")))]
+        {
+            panic!("this example only works on macOS")
+        }
     }
 
     /// We return a `Shared` `Id` because `general` can easily be called

objc2-foundation/examples/nsspeechsynthesizer.rs

@@ -8,7 +8,7 @@ use std::time::Duration;
 
 use objc2::rc::{Id, Owned};
 use objc2::runtime::Class;
-use objc2::{class, msg_send, msg_send_bool, msg_send_id};
+use objc2::{msg_send, msg_send_bool, msg_send_id};
 use objc2::{Encoding, Message, RefEncode};
 
 use objc2_foundation::{NSObject, NSString};
@@ -47,7 +47,14 @@ impl DerefMut for NSSpeechSynthesizer {
 // TODO: Unsure about when to use `&mut` here?
 impl NSSpeechSynthesizer {
     pub fn class() -> &'static Class {
-        class!(NSSpeechSynthesizer)
+        #[cfg(all(feature = "apple", target_os = "macos"))]
+        {
+            objc2::class!(NSSpeechSynthesizer)
+        }
+        #[cfg(not(all(feature = "apple", target_os = "macos")))]
+        {
+            panic!("this example only works on macOS")
+        }
     }
 
     // Uses default voice

objc2-foundation/src/declare_macro.rs

@@ -515,7 +515,7 @@ macro_rules! declare_class {
                 use $crate::__std::sync::Once;
 
                 use $crate::objc2::declare::ClassBuilder;
-                use $crate::objc2::runtime::Protocol;
+                use $crate::objc2::runtime::{Class, Protocol};
                 static REGISTER_CLASS: Once = Once::new();
 
                 REGISTER_CLASS.call_once(|| {
@@ -555,7 +555,8 @@ macro_rules! declare_class {
                     let _cls = builder.register();
                 });
 
-                $crate::objc2::class!($name)
+                // We just registered the class, so it should be available
+                Class::get(stringify!($name)).unwrap()
             }
         }
 

objc2-foundation/src/lib.rs

@@ -66,6 +66,7 @@ pub use self::process_info::NSProcessInfo;
 pub use self::range::NSRange;
 pub use self::string::NSString;
 pub use self::thread::{is_main_thread, is_multi_threaded, MainThreadMarker, NSThread};
+#[cfg(not(macos_10_7))] // Temporary
 pub use self::uuid::NSUUID;
 pub use self::value::NSValue;
 pub use self::zone::NSZone;
@@ -112,6 +113,8 @@ mod process_info;
 mod range;
 mod string;
 mod thread;
+// Temporarily disable testing UUID on macOS 10.7 until
+#[cfg(not(macos_10_7))]
 mod uuid;
 mod value;
 mod zone;
@@ -175,6 +178,7 @@ mod tests {
         assert_auto_traits::<NSString>();
         assert_unwindsafe::<MainThreadMarker>(); // Intentional
         assert_auto_traits::<NSThread>();
+        #[cfg(not(macos_10_7))]
         assert_auto_traits::<NSUUID>();
         assert_auto_traits::<NSValue<i32>>();
         assert_unwindsafe::<NSZone>(); // Intentional

objc2-foundation/src/uuid.rs

@@ -15,6 +15,8 @@ extern_class! {
     /// Conversion methods to/from UUIDs from the `uuid` crate can be
     /// enabled with the `uuid` crate feature.
     ///
+    /// macOS: This is only available on 10.8 and above.
+    ///
     /// See [Apple's documentation](https://developer.apple.com/documentation/foundation/nsuuid?language=objc).
     #[derive(PartialEq, Eq, Hash)]
     unsafe pub struct NSUUID: NSObject;

objc2/CHANGELOG.md

@@ -6,6 +6,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ## Unreleased - YYYY-MM-DD
 
+### Added
+* Added the `"unstable-static-class"` and `"unstable-static-class-inlined"`
+  feature flags to make the `class!` macro zero cost.
+
 
 ## 0.3.0-beta.1 - 2022-07-19
 

objc2/Cargo.toml

@@ -51,6 +51,8 @@ malloc = ["malloc_buf"]
 # https://github.com/madsmtm/objc2/issues/new
 unstable-static-sel = ["objc2-proc-macros"]
 unstable-static-sel-inlined = ["unstable-static-sel"]
+unstable-static-class = ["objc2-proc-macros"]
+unstable-static-class-inlined = ["unstable-static-class"]
 
 # Uses nightly features to make AutoreleasePool zero-cost even in debug mode
 unstable-autoreleasesafe = []

objc2/examples/introspection.rs

@@ -4,6 +4,10 @@ use objc2::{class, msg_send, msg_send_id};
 #[cfg(feature = "malloc")]
 use objc2::{sel, Encode};
 
+#[cfg(feature = "apple")]
+#[link(name = "Foundation", kind = "framework")]
+extern "C" {}
+
 fn main() {
     // Get a class
     let cls = class!(NSObject);

objc2/examples/talk_to_me.rs

@@ -3,19 +3,29 @@
 //! **Untested**!
 //!
 //! Works on macOS >= 10.15 or iOS > 7.0!
-use objc2::ffi::NSUInteger;
-use objc2::rc::{Id, Owned, Shared};
-use objc2::runtime::Object;
-use objc2::{class, msg_send, msg_send_bool, msg_send_id};
-use std::ffi::c_void;
 
-#[cfg(feature = "apple")]
-#[link(name = "AVFoundation", kind = "framework")]
-extern "C" {}
-
-const UTF8_ENCODING: NSUInteger = 4;
+#[cfg(not(talk_to_me_example))]
+fn main() {
+    panic!("pass the `--cfg talk_to_me_example` flag to run this example!");
+}
 
+#[cfg(talk_to_me_example)]
 fn main() {
+    use objc2::ffi::NSUInteger;
+    use objc2::rc::{Id, Owned, Shared};
+    use objc2::runtime::Object;
+    use objc2::{class, msg_send, msg_send_bool, msg_send_id};
+    use std::ffi::c_void;
+
+    #[cfg(feature = "apple")]
+    #[link(name = "AVFoundation", kind = "framework")]
+    extern "C" {}
+    #[cfg(feature = "apple")]
+    #[link(name = "Foundation", kind = "framework")]
+    extern "C" {}
+
+    const UTF8_ENCODING: NSUInteger = 4;
+
     let text = "Hello from Rust!";
 
     // Note: objc2-foundation has functionality to do this safely!

objc2/src/__macro_helpers.rs

@@ -211,6 +211,35 @@ pub const fn in_selector_family(mut selector: &[u8], mut family: &[u8]) -> bool
     }
 }
 
+/// Helper struct for emitting the module info that macOS 32-bit requires.
+///
+/// <https://github.com/llvm/llvm-project/blob/release/13.x/clang/lib/CodeGen/CGObjCMac.cpp#L5211-L5234>
+#[repr(C)]
+pub struct ModuleInfo {
+    version: usize,
+    size: usize,
+    name: *const u8,
+    symtab: *const (),
+}
+
+// SAFETY: ModuleInfo is immutable.
+unsafe impl Sync for ModuleInfo {}
+
+impl ModuleInfo {
+    /// This is hardcoded in clang as 7.
+    const VERSION: usize = 7;
+
+    pub const fn new(name: *const u8) -> Self {
+        Self {
+            version: Self::VERSION,
+            size: core::mem::size_of::<Self>(),
+            name,
+            // We don't expose any symbols
+            symtab: core::ptr::null(),
+        }
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -441,4 +470,13 @@ mod tests {
         // to be different!
         assert_eq!(ident1, ident2);
     }
+
+    #[test]
+    #[cfg_attr(
+        not(all(feature = "apple", target_os = "macos", target_arch = "x86")),
+        ignore = "Only relevant on macOS 32-bit"
+    )]
+    fn ensure_size_of_module_info() {
+        assert_eq!(core::mem::size_of::<ModuleInfo>(), 16);
+    }
 }

objc2/src/lib.rs

@@ -218,6 +218,11 @@ mod test_utils;
 #[cfg(feature = "malloc")]
 mod verify;
 
+// Hack to make doctests work
+#[cfg(all(feature = "apple", feature = "unstable-static-class"))]
+#[link(name = "Foundation", kind = "framework")]
+extern "C" {}
+
 /// Hacky way to make GNUStep link properly to Foundation while testing.
 ///
 /// This is a temporary solution to make our CI work for now!