auto merge of #15427 : aochagavia/rust/parse, r=pcwalton

Author: bors

src/libsyntax/parse/mod.rs

@@ -278,11 +278,7 @@ pub fn maybe_aborted<T>(result: T, mut p: Parser) -> T {
 #[cfg(test)]
 mod test {
     use super::*;
-    use serialize::{json, Encodable};
-    use std::io;
-    use std::io::MemWriter;
-    use std::mem::transmute;
-    use std::str;
+    use serialize::json;
     use std::gc::GC;
     use codemap::{Span, BytePos, Spanned};
     use owned_slice::OwnedSlice;
@@ -296,16 +292,6 @@ mod test {
     use util::parser_testing::{string_to_expr, string_to_item};
     use util::parser_testing::string_to_stmt;
 
-    fn to_json_str<'a, E: Encodable<json::Encoder<'a>, io::IoError>>(val: &E) -> String {
-        let mut writer = MemWriter::new();
-        // FIXME(14302) remove the transmute and unsafe block.
-        unsafe {
-            let mut encoder = json::Encoder::new(&mut writer as &mut io::Writer);
-            let _ = val.encode(transmute(&mut encoder));
-        }
-        str::from_utf8(writer.unwrap().as_slice()).unwrap().to_string()
-    }
-
     // produce a codemap::span
     fn sp(a: u32, b: u32) -> Span {
         Span{lo:BytePos(a),hi:BytePos(b),expn_info:None}
@@ -415,7 +401,7 @@ mod test {
 
     #[test] fn string_to_tts_1 () {
         let tts = string_to_tts("fn a (b : int) { b; }".to_string());
-        assert_eq!(to_json_str(&tts),
+        assert_eq!(json::encode(&tts),
         "[\
     {\
         \"variant\":\"TTTok\",\