libcore: Remove all uses of `~str` from `libcore`.

[breaking-change]

2 files changed, 8 insertions, 7 deletions

diff --git a/src/libstd/io/fs.rs b/src/libstd/io/fs.rs
index 6feaf10d5c5..d8edd6517d5 100644
--- a/src/libstd/io/fs.rs
+++ b/src/libstd/io/fs.rs
@@ -855,7 +855,7 @@ mod test {
         }
         check!(unlink(filename));
         let read_str = str::from_utf8(read_mem).unwrap();
-        assert!(read_str == final_msg.to_owned());
+        assert!(read_str.as_slice() == final_msg.as_slice());
     })
 
     iotest!(fn file_test_io_seek_shakedown() {
@@ -955,9 +955,8 @@ mod test {
         for n in range(0,3) {
             let f = dir.join(format_strbuf!("{}.txt", n));
             let mut w = check!(File::create(&f));
-            let msg_str =
-                (prefix + n.to_str().into_owned()).to_owned();
-            let msg = msg_str.as_bytes();
+            let msg_str = format!("{}{}", prefix, n.to_str());
+            let msg = msg_str.as_slice().as_bytes();
             check!(w.write(msg));
         }
         let files = check!(readdir(dir));
@@ -969,7 +968,7 @@ mod test {
                 let read_str = str::from_utf8(mem).unwrap();
                 let expected = match n {
                     None|Some("") => fail!("really shouldn't happen.."),
-                    Some(n) => prefix+n
+                    Some(n) => format!("{}{}", prefix, n),
                 };
                 assert_eq!(expected.as_slice(), read_str);
             }
diff --git a/src/libstd/io/process.rs b/src/libstd/io/process.rs
index f1f3e0a468a..7d84530282f 100644
--- a/src/libstd/io/process.rs
+++ b/src/libstd/io/process.rs
@@ -827,10 +827,12 @@ mod tests {
         for &(ref k, ref v) in r.iter() {
             // don't check android RANDOM variables
             if *k != "RANDOM".to_strbuf() {
-                assert!(output.contains(format!("{}={}",
+                assert!(output.as_slice()
+                              .contains(format!("{}={}",
                                                 *k,
                                                 *v).as_slice()) ||
-                        output.contains(format!("{}=\'{}\'",
+                        output.as_slice()
+                              .contains(format!("{}=\'{}\'",
                                                 *k,
                                                 *v).as_slice()));
             }