Merge pull request #482 from Flying-Toast/append-cow

implement Append for Cow<'a, str> and Cow<'a, [T]>

dbus/src/arg/array_impl.rs

@@ -8,6 +8,7 @@ use std::ffi::{CString};
 use std::os::raw::{c_void, c_int};
 use std::collections::{HashMap, BTreeMap};
 use std::hash::{Hash, BuildHasher};
+use std::borrow::Cow;
 
 // Map DBus-Type -> Alignment. Copied from _dbus_marshal_write_fixed_multi in
 // http://dbus.freedesktop.org/doc/api/html/dbus-marshal-basic_8c_source.html#l01020
@@ -53,6 +54,12 @@ impl<'a, T: Arg + Append + Clone> Append for &'a [T] {
     }
 }
 
+impl<'a, T: Arg + Append + Clone> Append for Cow<'a, [T]> {
+    fn append_by_ref(&self, i: &mut IterAppend) {
+        (&*self).append_by_ref(i)
+    }
+}
+
 impl<'a, T: Arg + RefArg> RefArg for &'a [T] {
     fn arg_type(&self) -> ArgType { ArgType::Array }
     fn signature(&self) -> Signature<'static> { Signature::from(format!("a{}", <T as Arg>::signature())) }

dbus/src/arg/basic_impl.rs

@@ -6,6 +6,7 @@ use std::{ptr, any, mem};
 use std::ffi::CStr;
 use std::os::raw::{c_void, c_char, c_int};
 use std::fs::File;
+use std::borrow::Cow;
 
 
 fn arg_append_basic<T>(i: *mut ffi::DBusMessageIter, arg_type: ArgType, v: T) {
@@ -184,6 +185,12 @@ impl<'a> Get<'a> for &'a str {
         .and_then(|s| s.to_str().ok()) }
 }
 
+impl<'a> Append for Cow<'a, str> {
+    fn append_by_ref(&self, i: &mut IterAppend) {
+        (&*self).append_by_ref(i)
+    }
+}
+
 impl<'a> Arg for String {
     const ARG_TYPE: ArgType = ArgType::String;
     fn signature() -> Signature<'static> { unsafe { Signature::from_slice_unchecked("s\0") } }