Auto merge of #187 - jrmuizel:dict, r=jdm

Give CFDictionary type parameters for keys and values

There's more to be done to clean up the interface now that we have
type parameters but this is a good place to start.

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core-foundation/src/dictionary.rs

@@ -11,23 +11,29 @@
 
 pub use core_foundation_sys::dictionary::*;
 
-use core_foundation_sys::base::{CFTypeRef, kCFAllocatorDefault};
+use core_foundation_sys::base::{CFTypeRef, CFRelease, kCFAllocatorDefault};
 use std::mem;
 use std::os::raw::c_void;
 use std::ptr;
+use std::marker::PhantomData;
+
 
 use base::{CFType, CFIndexConvertible, TCFType, TCFTypeRef};
 
+// consume the type parameters with PhantomDatas
+pub struct CFDictionary<K = *const c_void, V = *const c_void>(CFDictionaryRef, PhantomData<K>, PhantomData<V>);
 
-declare_TCFType!{
-    /// An immutable dictionary of key-value pairs.
-    CFDictionary, CFDictionaryRef
+impl<K, V> Drop for CFDictionary<K, V> {
+    fn drop(&mut self) {
+        unsafe { CFRelease(self.as_CFTypeRef()) }
+    }
 }
-impl_TCFType!(CFDictionary, CFDictionaryRef, CFDictionaryGetTypeID);
+
+impl_TCFType!(CFDictionary<K, V>, CFDictionaryRef, CFDictionaryGetTypeID);
 impl_CFTypeDescription!(CFDictionary);
 
-impl CFDictionary {
-    pub fn from_CFType_pairs<K: TCFType, V: TCFType>(pairs: &[(K, V)]) -> CFDictionary {
+impl<K, V> CFDictionary<K, V> {
+    pub fn from_CFType_pairs(pairs: &[(K, V)]) -> CFDictionary<K, V> where K: TCFType, V: TCFType {
         let (keys, values): (Vec<CFTypeRef>, Vec<CFTypeRef>) = pairs
             .iter()
             .map(|&(ref key, ref value)| (key.as_CFTypeRef(), value.as_CFTypeRef()))
@@ -64,7 +70,7 @@ impl CFDictionary {
     /// Similar to `contains_key` but acts on a higher level, automatically converting from any
     /// `TCFType` to the raw pointer of its concrete TypeRef.
     #[inline]
-    pub fn contains_key2<K: TCFType>(&self, key: &K) -> bool {
+    pub fn contains_key2(&self, key: &K) -> bool where K: TCFType {
         self.contains_key(key.as_concrete_TypeRef().as_void_ptr())
     }
 
@@ -83,7 +89,7 @@ impl CFDictionary {
     /// Similar to `find` but acts on a higher level, automatically converting from any `TCFType`
     /// to the raw pointer of its concrete TypeRef.
     #[inline]
-    pub fn find2<K: TCFType>(&self, key: &K) -> Option<*const c_void> {
+    pub fn find2(&self, key: &K) -> Option<*const c_void> where K: TCFType {
         self.find(key.as_concrete_TypeRef().as_void_ptr())
     }
 

core-graphics/src/font.rs

@@ -8,7 +8,7 @@
 // except according to those terms.
 
 use std::ptr;
-use core_foundation::base::{CFRelease, CFRetain, CFTypeID, TCFType};
+use core_foundation::base::{CFRelease, CFRetain, CFTypeID, TCFType, CFType};
 use core_foundation::array::{CFArray, CFArrayRef};
 use core_foundation::data::{CFData, CFDataRef};
 use core_foundation::string::{CFString, CFStringRef};
@@ -63,7 +63,7 @@ impl CGFont {
         }
     }
 
-    pub fn create_copy_from_variations(&self, vars: &CFDictionary) -> Result<CGFont, ()> {
+    pub fn create_copy_from_variations(&self, vars: &CFDictionary<CFType, CFType>) -> Result<CGFont, ()> {
         unsafe {
             let font_ref = CGFontCreateCopyWithVariations(self.as_ptr(),
                                                           vars.as_concrete_TypeRef());

core-text/src/font_descriptor.rs

@@ -114,7 +114,7 @@ impl StylisticClassAccessors for CTFontStylisticClass {
 
 pub type CTFontAttributes = CFDictionary;
 
-pub type CTFontTraits = CFDictionary;
+pub type CTFontTraits = CFDictionary<CFType, CFType>;
 
 pub trait TraitAccessors {
     fn symbolic_traits(&self) -> CTFontSymbolicTraits;
@@ -130,8 +130,7 @@ trait TraitAccessorPrivate {
 impl TraitAccessorPrivate for CTFontTraits {
     unsafe fn extract_number_for_key(&self, key: CFStringRef) -> CFNumber {
         let cftype = self.get_CFType(mem::transmute(key));
-        assert!(cftype.instance_of::<CFNumber>());
-        CFNumber::wrap_under_get_rule(mem::transmute(cftype.as_CFTypeRef()))
+        cftype.downcast::<CFNumber>().unwrap()
     }
 
 }
@@ -269,7 +268,7 @@ impl CTFontDescriptor {
     }
 }
 
-pub fn new_from_attributes(attributes: &CFDictionary) -> CTFontDescriptor {
+pub fn new_from_attributes(attributes: &CFDictionary<CFType, CFType>) -> CTFontDescriptor {
     unsafe {
         let result: CTFontDescriptorRef =
             CTFontDescriptorCreateWithAttributes(attributes.as_concrete_TypeRef());