glib: Make Object::new() generic

This avoids the explicit downcast in the common usage of the function. The previous function is available as `Object::with_type()`. Also requires a gir update and regenerating with it.
gtk-rs · Dec 17, 2020 · 7e1f8b0 · 7e1f8b0
1 parent 8347965
commit 7e1f8b0
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Showing 11 changed files with 44 additions and 77 deletions.
diff --git a/examples/src/bin/basic_subclass.rs b/examples/src/bin/basic_subclass.rs
@@ -113,10 +113,7 @@ glib_wrapper! {
 
 impl SimpleWindow {
     pub fn new(app: &SimpleApplication) -> Self {
-        glib::Object::new(Self::static_type(), &[("application", app)])
-            .expect("Failed to create SimpleWindow")
-            .downcast::<SimpleWindow>()
-            .expect("Created SimpleWindow is of wrong type")
+        glib::Object::new(&[("application", app)]).expect("Failed to create SimpleWindow")
     }
 }
 
@@ -196,16 +193,11 @@ glib_wrapper! {
 impl SimpleApplication {
     #[allow(clippy::new_without_default)]
     pub fn new() -> Self {
-        glib::Object::new(
-            Self::static_type(),
-            &[
-                ("application-id", &"org.gtk-rs.SimpleApplication"),
-                ("flags", &ApplicationFlags::empty()),
-            ],
-        )
+        glib::Object::new(&[
+            ("application-id", &"org.gtk-rs.SimpleApplication"),
+            ("flags", &ApplicationFlags::empty()),
+        ])
         .expect("Failed to create SimpleApp")
-        .downcast()
-        .expect("Created simpleapp is of wrong type")
     }
 }
 

diff --git a/examples/src/bin/composite_template.rs b/examples/src/bin/composite_template.rs
@@ -78,10 +78,7 @@ glib_wrapper! {
 
 impl ExApplicationWindow {
     pub fn new<P: glib::IsA<gtk::Application>>(app: &P) -> Self {
-        glib::Object::new(Self::static_type(), &[("application", app)])
-            .expect("Failed to create ExApplicationWindow")
-            .downcast::<ExApplicationWindow>()
-            .expect("Created object is of wrong type")
+        glib::Object::new(&[("application", app)]).expect("Failed to create ExApplicationWindow")
     }
 
     pub fn init_label(&self) {

diff --git a/examples/src/bin/listbox_model.rs b/examples/src/bin/listbox_model.rs
@@ -81,10 +81,7 @@ mod model {
     impl Model {
         #[allow(clippy::new_without_default)]
         pub fn new() -> Model {
-            glib::Object::new(Self::static_type(), &[])
-                .expect("Failed to create Model")
-                .downcast()
-                .expect("Created Model is of wrong type")
+            glib::Object::new(&[]).expect("Failed to create Model")
         }
 
         pub fn append(&self, obj: &RowData) {
@@ -413,10 +410,8 @@ mod row_data {
     // initial values for our two properties and then returns the new instance
     impl RowData {
         pub fn new(name: &str, count: u32) -> RowData {
-            glib::Object::new(Self::static_type(), &[("name", &name), ("count", &count)])
+            glib::Object::new(&[("name", &name), ("count", &count)])
                 .expect("Failed to create row data")
-                .downcast()
-                .expect("Created row data is of wrong type")
         }
     }
 }
diff --git a/gio/src/read_input_stream.rs b/gio/src/read_input_stream.rs
@@ -164,10 +164,7 @@ glib::glib_wrapper! {
 
 impl ReadInputStream {
     pub fn new<R: Read + Send + 'static>(read: R) -> ReadInputStream {
-        let obj = glib::Object::new(Self::static_type(), &[])
-            .expect("Failed to create read input stream")
-            .downcast()
-            .expect("Created read input stream is of wrong type");
+        let obj = glib::Object::new(&[]).expect("Failed to create read input stream");
 
         let imp = imp::ReadInputStream::from_instance(&obj);
         *imp.read.borrow_mut() = Some(imp::Reader::Read(AnyReader::new(read)));
@@ -176,10 +173,7 @@ impl ReadInputStream {
     }
 
     pub fn new_seekable<R: Read + Seek + Send + 'static>(read: R) -> ReadInputStream {
-        let obj = glib::Object::new(Self::static_type(), &[])
-            .expect("Failed to create read input stream")
-            .downcast()
-            .expect("Created read input stream is of wrong type");
+        let obj = glib::Object::new(&[]).expect("Failed to create read input stream");
 
         let imp = imp::ReadInputStream::from_instance(&obj);
         *imp.read.borrow_mut() = Some(imp::Reader::ReadSeek(AnyReader::new_seekable(read)));

diff --git a/gio/src/subclass/application.rs b/gio/src/subclass/application.rs
@@ -549,21 +549,18 @@ mod tests {
     }
 
     glib::glib_wrapper! {
-        pub struct SimpleApplication(ObjectSubclass<imp::SimpleApplication>);
+        pub struct SimpleApplication(ObjectSubclass<imp::SimpleApplication>)
+        @implements crate::Application;
     }
 
     #[test]
     fn test_simple_application() {
-        let app = glib::Object::new(
-            SimpleApplication::static_type(),
-            &[
-                ("application-id", &"org.gtk-rs.SimpleApplication"),
-                ("flags", &crate::ApplicationFlags::empty()),
-            ],
-        )
+        let app = glib::Object::new::<SimpleApplication>(&[
+            ("application-id", &"org.gtk-rs.SimpleApplication"),
+            ("flags", &crate::ApplicationFlags::empty()),
+        ])
         .unwrap()
-        .downcast::<crate::Application>()
-        .unwrap();
+        .upcast::<crate::Application>();
 
         app.set_inactivity_timeout(10000);
 

diff --git a/gio/src/subclass/input_stream.rs b/gio/src/subclass/input_stream.rs
@@ -363,10 +363,7 @@ mod tests {
 
     #[test]
     fn test_simple_stream() {
-        let stream = glib::Object::new(SimpleInputStream::static_type(), &[])
-            .unwrap()
-            .downcast::<SimpleInputStream>()
-            .unwrap();
+        let stream = glib::Object::new::<SimpleInputStream>(&[]).unwrap();
 
         let mut buf = [0; 16];
         assert_eq!(stream.read(&mut buf, crate::NONE_CANCELLABLE), Ok(16));

diff --git a/gio/src/subclass/output_stream.rs b/gio/src/subclass/output_stream.rs
@@ -369,10 +369,7 @@ mod tests {
 
     #[test]
     fn test_simple_stream() {
-        let stream = glib::Object::new(SimpleOutputStream::static_type(), &[])
-            .unwrap()
-            .downcast::<SimpleOutputStream>()
-            .unwrap();
+        let stream = glib::Object::new::<SimpleOutputStream>(&[]).unwrap();
 
         assert_eq!(
             *imp::SimpleOutputStream::from_instance(&stream).sum.borrow(),

diff --git a/gio/src/write_output_stream.rs b/gio/src/write_output_stream.rs
@@ -191,21 +191,15 @@ glib::glib_wrapper! {
 
 impl WriteOutputStream {
     pub fn new<W: Write + Send + Any + 'static>(write: W) -> WriteOutputStream {
-        let obj = glib::Object::new(Self::static_type(), &[])
-            .expect("Failed to create write input stream")
-            .downcast()
-            .expect("Created write input stream is of wrong type");
+        let obj = glib::Object::new(&[]).expect("Failed to create write input stream");
 
         let imp = imp::WriteOutputStream::from_instance(&obj);
         *imp.write.borrow_mut() = Some(imp::Writer::Write(AnyWriter::new(write)));
         obj
     }
 
     pub fn new_seekable<W: Write + Seek + Send + Any + 'static>(write: W) -> WriteOutputStream {
-        let obj = glib::Object::new(Self::static_type(), &[])
-            .expect("Failed to create write input stream")
-            .downcast()
-            .expect("Created write input stream is of wrong type");
+        let obj = glib::Object::new(&[]).expect("Failed to create write input stream");
 
         let imp = imp::WriteOutputStream::from_instance(&obj);
         *imp.write.borrow_mut() = Some(imp::Writer::WriteSeek(AnyWriter::new_seekable(write)));

diff --git a/glib/src/object.rs b/glib/src/object.rs
@@ -1069,7 +1069,17 @@ glib_object_wrapper!(@object
 pub type ObjectClass = Class<Object>;
 
 impl Object {
-    pub fn new(type_: Type, properties: &[(&str, &dyn ToValue)]) -> Result<Object, BoolError> {
+    #[allow(clippy::new_ret_no_self)]
+    pub fn new<T: IsA<Object>>(properties: &[(&str, &dyn ToValue)]) -> Result<T, BoolError> {
+        Ok(Object::with_type(T::static_type(), properties)?
+            .downcast()
+            .unwrap())
+    }
+
+    pub fn with_type(
+        type_: Type,
+        properties: &[(&str, &dyn ToValue)],
+    ) -> Result<Object, BoolError> {
         use std::ffi::CString;
 
         let klass = ObjectClass::from_type(type_)

diff --git a/glib/src/subclass/mod.rs b/glib/src/subclass/mod.rs
@@ -200,10 +200,7 @@
 //! impl SimpleObject {
 //!     // Create an object instance of the new type.
 //!     pub fn new() -> Self {
-//!         glib::Object::new(Self::static_type(), &[])
-//!             .unwrap()
-//!             .downcast()
-//!             .unwrap()
+//!         glib::Object::new(&[]).unwrap()
 //!     }
 //! }
 //!

diff --git a/glib/src/subclass/object.rs b/glib/src/subclass/object.rs
@@ -572,7 +572,7 @@ mod test {
     #[test]
     fn test_create() {
         let type_ = SimpleObject::static_type();
-        let obj = Object::new(type_, &[]).expect("Object::new failed");
+        let obj = Object::with_type(type_, &[]).expect("Object::new failed");
 
         assert!(obj.get_type().is_a(&DummyInterface::static_type()));
 
@@ -591,11 +591,7 @@ mod test {
 
     #[test]
     fn test_create_child_object() {
-        let type_ = ChildObject::static_type();
-        let obj = Object::new(type_, &[])
-            .expect("Object::new failed")
-            .downcast::<ChildObject>()
-            .unwrap();
+        let obj: ChildObject = Object::new(&[]).expect("Object::new failed");
 
         // ChildObject is a zero-sized type and we map that to the same pointer as the object
         // itself. No private/impl data is allocated for zero-sized types.
@@ -606,7 +602,7 @@ mod test {
 
     #[test]
     fn test_set_properties() {
-        let obj = Object::new(
+        let obj = Object::with_type(
             SimpleObject::static_type(),
             &[("construct-name", &"meh"), ("name", &"initial")],
         )
@@ -674,7 +670,8 @@ mod test {
             "property 'name' of type 'SimpleObject' can't be set from the given type (expected: 'gchararray', got: 'gboolean')",
         );
 
-        let other_obj = Object::new(SimpleObject::static_type(), &[]).expect("Object::new failed");
+        let other_obj =
+            Object::with_type(SimpleObject::static_type(), &[]).expect("Object::new failed");
         assert_eq!(
             obj.set_property("child", &other_obj)
                 .err()
@@ -683,7 +680,7 @@ mod test {
             "property 'child' of type 'SimpleObject' can't be set from the given object type (expected: 'ChildObject', got: 'SimpleObject')",
         );
 
-        let child = Object::new(ChildObject::static_type(), &[]).expect("Object::new failed");
+        let child = Object::with_type(ChildObject::static_type(), &[]).expect("Object::new failed");
         assert!(obj.set_property("child", &child).is_ok());
     }
 
@@ -693,7 +690,7 @@ mod test {
         use std::sync::Arc;
 
         let type_ = SimpleObject::static_type();
-        let obj = Object::new(type_, &[("name", &"old-name")]).expect("Object::new failed");
+        let obj = Object::with_type(type_, &[("name", &"old-name")]).expect("Object::new failed");
 
         let name_changed_triggered = Arc::new(AtomicBool::new(false));
         let name_changed_clone = name_changed_triggered.clone();
@@ -735,7 +732,7 @@ mod test {
 
     #[test]
     fn test_signal_return_expected_type() {
-        let obj = Object::new(SimpleObject::static_type(), &[]).expect("Object::new failed");
+        let obj = Object::with_type(SimpleObject::static_type(), &[]).expect("Object::new failed");
 
         obj.connect("create-string", false, move |_args| {
             Some("return value".to_value())
@@ -755,7 +752,7 @@ mod test {
         use std::sync::Arc;
 
         let type_ = SimpleObject::static_type();
-        let obj = Object::new(type_, &[("name", &"old-name")]).expect("Object::new failed");
+        let obj = Object::with_type(type_, &[("name", &"old-name")]).expect("Object::new failed");
 
         let name_changed_triggered = Arc::new(AtomicBool::new(false));
         let name_changed_clone = name_changed_triggered.clone();
@@ -772,11 +769,11 @@ mod test {
 
     #[test]
     fn test_signal_return_expected_object_type() {
-        let obj = Object::new(SimpleObject::static_type(), &[]).expect("Object::new failed");
+        let obj = Object::with_type(SimpleObject::static_type(), &[]).expect("Object::new failed");
 
         obj.connect("create-child-object", false, move |_args| {
             Some(
-                Object::new(ChildObject::static_type(), &[])
+                Object::with_type(ChildObject::static_type(), &[])
                     .expect("Object::new failed")
                     .to_value(),
             )