ThreadGuard: Implement ToValue, Fromvalue and Default traits

This will also allow ThreadGuard to be used with the new property
macro.

Author: alatiera

glib-macros/tests/properties.rs

@@ -87,6 +87,7 @@ mod foo {
     }
 
     pub mod imp {
+        use glib::thread_guard::ThreadGuard;
         use glib::{ParamSpec, Value};
         use std::rc::Rc;
 
@@ -145,6 +146,8 @@ mod foo {
             cell: Cell<u8>,
             #[property(get = Self::overridden, override_class = Base)]
             overridden: PhantomData<u32>,
+            #[property(get, set)]
+            thread_guard: ThreadGuard<Mutex<String>>,
         }
 
         impl ObjectImpl for Foo {
@@ -195,6 +198,12 @@ fn props() {
     let bar: String = myfoo.property("bar");
     assert_eq!(bar, "".to_string());
 
+    // Set the thread guard
+    myfoo.set_property("thread-guard", "foobar".to_value());
+    // And grab directly the string from the guard after
+    let bar: String = myfoo.property("thread-guard");
+    assert_eq!(bar, "foobar".to_string());
+
     // Set bar
     myfoo.set_property("bar", "epic".to_value());
     let bar: String = myfoo.property("bar");

glib/src/property.rs

@@ -9,6 +9,7 @@ use std::sync::Arc;
 use std::sync::Mutex;
 use std::sync::RwLock;
 
+use crate::thread_guard::ThreadGuard;
 use crate::HasParamSpec;
 
 // rustdoc-stripper-ignore-next
@@ -37,6 +38,9 @@ impl<T: Property> Property for Mutex<T> {
 impl<T: Property> Property for RwLock<T> {
     type Value = T::Value;
 }
+impl<T: Property> Property for ThreadGuard<T> {
+    type Value = T::Value;
+}
 impl<T: Property> Property for once_cell::sync::OnceCell<T> {
     type Value = T::Value;
 }
@@ -131,6 +135,19 @@ impl<T> PropertySetNested for RwLock<T> {
     }
 }
 
+impl<T: PropertyGet> PropertyGet for ThreadGuard<T> {
+    type Value = T::Value;
+    fn get<R, F: Fn(&Self::Value) -> R>(&self, f: F) -> R {
+        self.get_ref().get(f)
+    }
+}
+impl<T: PropertySetNested> PropertySetNested for ThreadGuard<T> {
+    type SetNestedValue = T::SetNestedValue;
+    fn set_nested<F: FnOnce(&mut Self::SetNestedValue)>(&self, f: F) {
+        self.get_ref().set_nested(f)
+    }
+}
+
 impl<T> PropertyGet for once_cell::sync::OnceCell<T> {
     type Value = T;
     fn get<R, F: Fn(&Self::Value) -> R>(&self, f: F) -> R {

glib/src/thread_guard.rs

@@ -4,6 +4,7 @@ use std::{
     mem, ptr,
     sync::atomic::{AtomicUsize, Ordering},
 };
+
 fn next_thread_id() -> usize {
     static COUNTER: AtomicUsize = AtomicUsize::new(0);
     COUNTER.fetch_add(1, Ordering::SeqCst)
@@ -111,4 +112,10 @@ impl<T> Drop for ThreadGuard<T> {
     }
 }
 
+impl<T: Default> Default for ThreadGuard<T> {
+    fn default() -> Self {
+        Self::new(T::default())
+    }
+}
+
 unsafe impl<T> Send for ThreadGuard<T> {}