Auto merge of #89 - cjhowe:feature-dictionary-keys-values, r=jdm

Add CFDictionary function to get keys and values

Tests included. No formatting issues this time!

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core-foundation-sys/src/dictionary.rs

@@ -72,4 +72,8 @@ extern {
     pub fn CFDictionarySetValue(theDict: CFMutableDictionaryRef,
                                 key: *const c_void,
                                 value: *const c_void);
+    pub fn CFDictionaryGetKeysAndValues(theDict: CFDictionaryRef,
+                                        keys: *mut *const c_void,
+                                        values: *mut *const c_void);
+
 }

core-foundation/src/dictionary.rs

@@ -101,4 +101,18 @@ impl CFDictionary {
     pub unsafe fn set_value(&self, key: *const c_void, value: *const c_void) {
         CFDictionarySetValue(self.0, key, value)
     }
+
+    pub fn get_keys_and_values(&self) -> (Vec<*const c_void>, Vec<*const c_void>) {
+        let length = self.len();
+        let mut keys = Vec::with_capacity(length);
+        let mut values = Vec::with_capacity(length);
+
+        unsafe {
+            CFDictionaryGetKeysAndValues(self.0, keys.as_mut_ptr(), values.as_mut_ptr());
+            keys.set_len(length);
+            values.set_len(length);
+        }
+
+        (keys, values)
+    }
 }

core-foundation/src/lib.rs

@@ -84,10 +84,15 @@ pub mod test {
         let tru = CFBoolean::true_value();
         let n42 = number(42);
 
-        let _d = CFDictionary::from_CFType_pairs(&[
+        let d = CFDictionary::from_CFType_pairs(&[
             (bar.as_CFType(), boo.as_CFType()),
             (baz.as_CFType(), tru.as_CFType()),
             (foo.as_CFType(), n42.as_CFType()),
         ]);
+
+        let (v1, v2) = d.get_keys_and_values();
+
+        assert!(v1 == &[bar.as_CFTypeRef(), baz.as_CFTypeRef(), foo.as_CFTypeRef()]);
+        assert!(v2 == &[boo.as_CFTypeRef(), tru.as_CFTypeRef(), n42.as_CFTypeRef()]);
     }
 }