libproc_macro: Implement Extend for TokenStream

Implement extension from TokenTree and TokenStream iterators on
TokenStream rust type.

ChangeLog:

	* librust/proc_macro/rust/bridge/token_stream.rs: Add internal
	implementation for TokenStream extension.
	* librust/proc_macro/rust/lib.rs: Add call to internal.

Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

2 files changed, 22 insertions, 4 deletions

diff --git a/librust/proc_macro/rust/bridge/token_stream.rs b/librust/proc_macro/rust/bridge/token_stream.rs
index 7135a0f..027f450 100644
--- a/librust/proc_macro/rust/bridge/token_stream.rs
+++ b/librust/proc_macro/rust/bridge/token_stream.rs
@@ -85,3 +85,21 @@ impl TokenStream {
         result
     }
 }
+
+impl Extend<ExternalTokenTree> for TokenStream {
+    fn extend<I: IntoIterator<Item = ExternalTokenTree>>(&mut self, trees: I) {
+        for tt in trees {
+            self.push(tt.into())
+        }
+    }
+}
+
+impl Extend<ExternalTokenStream> for TokenStream {
+    fn extend<I: IntoIterator<Item = ExternalTokenStream>>(&mut self, streams: I) {
+        for stream in streams {
+            for tt in stream {
+                self.push(tt.into());
+            }
+        }
+    }
+}
diff --git a/librust/proc_macro/rust/lib.rs b/librust/proc_macro/rust/lib.rs
index 4888edb..31676f1 100644
--- a/librust/proc_macro/rust/lib.rs
+++ b/librust/proc_macro/rust/lib.rs
@@ -186,13 +186,13 @@ impl iter::FromIterator<TokenStream> for TokenStream {
 }
 
 impl Extend<TokenTree> for TokenStream {
-    fn extend<I: IntoIterator<Item = TokenTree>>(&mut self, _trees: I) {
-        todo!("Implement this function")
+    fn extend<I: IntoIterator<Item = TokenTree>>(&mut self, trees: I) {
+        self.0.extend(trees);
     }
 }
 
 impl Extend<TokenStream> for TokenStream {
-    fn extend<I: IntoIterator<Item = TokenStream>>(&mut self, _streams: I) {
-        todo!("Implement this function")
+    fn extend<I: IntoIterator<Item = TokenStream>>(&mut self, streams: I) {
+        self.0.extend(streams)
     }
 }