auto merge of #15493 : brson/rust/tostr, r=pcwalton

This updates https://github.com/rust-lang/rust/pull/15075.

Rename `ToStr::to_str` to `ToString::to_string`. The naive renaming ends up with two `to_string` functions defined on strings in the prelude (the other defined via `collections::str::StrAllocating`). To remedy this I removed `StrAllocating::to_string`, making all conversions from `&str` to `String` go through `Show`. This has a measurable impact on the speed of this conversion, but the sense I get from others is that it's best to go ahead and unify `to_string` and address performance for all `to_string` conversions in `core::fmt`. `String::from_str(...)` still works as a manual fast-path.

Note that the patch was done with a script, and ended up renaming a number of other `*_to_str` functions, particularly inside of rustc. All the ones I saw looked correct, and I didn't notice any additional API breakage.

Closes #15046.

2 files changed, 3 insertions, 3 deletions

diff --git a/src/libdebug/fmt.rs b/src/libdebug/fmt.rs
index 4087cb95271..0b04a07ea88 100644
--- a/src/libdebug/fmt.rs
+++ b/src/libdebug/fmt.rs
@@ -45,7 +45,7 @@ impl<T> Poly for T {
             // If we have a specified width for formatting, then we have to make
             // this allocation of a new string
             _ => {
-                let s = repr::repr_to_str(self);
+                let s = repr::repr_to_string(self);
                 f.pad(s.as_slice())
             }
         }
diff --git a/src/libdebug/repr.rs b/src/libdebug/repr.rs
index 133353ec3d7..3e541929dbf 100644
--- a/src/libdebug/repr.rs
+++ b/src/libdebug/repr.rs
@@ -73,7 +73,7 @@ int_repr!(u64, "u64")
 
 macro_rules! num_repr(($ty:ident, $suffix:expr) => (impl Repr for $ty {
     fn write_repr(&self, writer: &mut io::Writer) -> io::IoResult<()> {
-        let s = self.to_str();
+        let s = self.to_string();
         writer.write(s.as_bytes()).and_then(|()| {
             writer.write($suffix)
         })
@@ -564,7 +564,7 @@ pub fn write_repr<T>(writer: &mut io::Writer, object: &T) -> io::IoResult<()> {
     }
 }
 
-pub fn repr_to_str<T>(t: &T) -> String {
+pub fn repr_to_string<T>(t: &T) -> String {
     let mut result = io::MemWriter::new();
     write_repr(&mut result as &mut io::Writer, t).unwrap();
     String::from_utf8(result.unwrap()).unwrap()