auto merge of #19378 : japaric/rust/no-as-slice, r=alexcrichton

Now that we have an overloaded comparison (`==`) operator, and that `Vec`/`String` deref to `[T]`/`str` on method calls, many `as_slice()`/`as_mut_slice()`/`to_string()` calls have become redundant. This patch removes them. These were the most common patterns:

- `assert_eq(test_output.as_slice(), "ground truth")` -> `assert_eq(test_output, "ground truth")`
- `assert_eq(test_output, "ground truth".to_string())` -> `assert_eq(test_output, "ground truth")`
- `vec.as_mut_slice().sort()` -> `vec.sort()`
- `vec.as_slice().slice(from, to)` -> `vec.slice(from_to)`

---

Note that e.g. `a_string.push_str(b_string.as_slice())` has been left untouched in this PR, since we first need to settle down whether we want to favor the `&*b_string` or the `b_string[]` notation.

This is rebased on top of #19167

cc @alexcrichton @aturon 

1 files changed, 11 insertions, 11 deletions

diff --git a/src/libstd/io/mod.rs b/src/libstd/io/mod.rs
index e0857fd27ff..d43a7a66c5b 100644
--- a/src/libstd/io/mod.rs
+++ b/src/libstd/io/mod.rs
@@ -240,8 +240,8 @@ use boxed::Box;
 use result::Result;
 use result::Result::{Ok, Err};
 use sys;
-use slice::{AsSlice, SlicePrelude};
-use str::{Str, StrPrelude};
+use slice::SlicePrelude;
+use str::StrPrelude;
 use str;
 use string::String;
 use uint;
@@ -318,7 +318,7 @@ impl IoError {
     pub fn from_errno(errno: uint, detail: bool) -> IoError {
         let mut err = sys::decode_error(errno as i32);
         if detail && err.kind == OtherIoError {
-            err.detail = Some(os::error_string(errno).as_slice().chars()
+            err.detail = Some(os::error_string(errno).chars()
                                  .map(|c| c.to_lowercase()).collect())
         }
         err
@@ -2007,14 +2007,14 @@ mod tests {
     fn test_show() {
         use super::*;
 
-        assert_eq!(format!("{}", USER_READ), "0400".to_string());
-        assert_eq!(format!("{}", USER_FILE), "0644".to_string());
-        assert_eq!(format!("{}", USER_EXEC), "0755".to_string());
-        assert_eq!(format!("{}", USER_RWX),  "0700".to_string());
-        assert_eq!(format!("{}", GROUP_RWX), "0070".to_string());
-        assert_eq!(format!("{}", OTHER_RWX), "0007".to_string());
-        assert_eq!(format!("{}", ALL_PERMISSIONS), "0777".to_string());
-        assert_eq!(format!("{}", USER_READ | USER_WRITE | OTHER_WRITE), "0602".to_string());
+        assert_eq!(format!("{}", USER_READ), "0400");
+        assert_eq!(format!("{}", USER_FILE), "0644");
+        assert_eq!(format!("{}", USER_EXEC), "0755");
+        assert_eq!(format!("{}", USER_RWX),  "0700");
+        assert_eq!(format!("{}", GROUP_RWX), "0070");
+        assert_eq!(format!("{}", OTHER_RWX), "0007");
+        assert_eq!(format!("{}", ALL_PERMISSIONS), "0777");
+        assert_eq!(format!("{}", USER_READ | USER_WRITE | OTHER_WRITE), "0602");
     }
 
     fn _ensure_buffer_is_object_safe<T: Buffer>(x: &T) -> &Buffer {