librand: Remove all uses of ~str from librand

Author: pcwalton

src/librand/lib.rs

@@ -260,15 +260,15 @@ pub trait Rng {
     ///
     /// println!("{}", task_rng().gen_ascii_str(10));
     /// ```
-    fn gen_ascii_str(&mut self, len: uint) -> ~str {
+    fn gen_ascii_str(&mut self, len: uint) -> StrBuf {
         static GEN_ASCII_STR_CHARSET: &'static [u8] = bytes!("ABCDEFGHIJKLMNOPQRSTUVWXYZ\
                                                              abcdefghijklmnopqrstuvwxyz\
                                                              0123456789");
         let mut s = StrBuf::with_capacity(len);
         for _ in range(0, len) {
             s.push_char(self.choose(GEN_ASCII_STR_CHARSET) as char)
         }
-        s.into_owned()
+        s
     }
 
     /// Choose an item randomly, failing if `values` is empty.

src/libregex/test/bench.rs

@@ -159,7 +159,7 @@ fn gen_text(n: uint) -> StrBuf {
             *b = '\n' as u8
         }
     }
-    str::from_utf8(bytes).unwrap().to_strbuf()
+    str::from_utf8(bytes.as_slice()).unwrap().to_strbuf()
 }
 
 throughput!(easy0_32, easy0(), 32)

src/libstd/os.rs

@@ -1511,9 +1511,9 @@ mod tests {
 
     fn make_rand_name() -> ~str {
         let mut rng = rand::task_rng();
-        let n = "TEST".to_owned() + rng.gen_ascii_str(10u);
-        assert!(getenv(n).is_none());
-        n
+        let n = format_strbuf!("TEST{}", rng.gen_ascii_str(10u).as_slice());
+        assert!(getenv(n.as_slice()).is_none());
+        n.into_owned()
     }
 
     #[test]