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/time/duration.rs b/src/libstd/time/duration.rs
index 63eb9a98736..86c3a1fdd32 100644
--- a/src/libstd/time/duration.rs
+++ b/src/libstd/time/duration.rs
@@ -540,20 +540,20 @@ mod tests {
 
     #[test]
     fn test_duration_fmt() {
-        assert_eq!(Duration::zero().to_string(), "PT0S".to_string());
-        assert_eq!(Duration::days(42).to_string(), "P42D".to_string());
-        assert_eq!(Duration::days(-42).to_string(), "-P42D".to_string());
-        assert_eq!(Duration::seconds(42).to_string(), "PT42S".to_string());
-        assert_eq!(Duration::milliseconds(42).to_string(), "PT0.042S".to_string());
-        assert_eq!(Duration::microseconds(42).to_string(), "PT0.000042S".to_string());
-        assert_eq!(Duration::nanoseconds(42).to_string(), "PT0.000000042S".to_string());
+        assert_eq!(Duration::zero().to_string(), "PT0S");
+        assert_eq!(Duration::days(42).to_string(), "P42D");
+        assert_eq!(Duration::days(-42).to_string(), "-P42D");
+        assert_eq!(Duration::seconds(42).to_string(), "PT42S");
+        assert_eq!(Duration::milliseconds(42).to_string(), "PT0.042S");
+        assert_eq!(Duration::microseconds(42).to_string(), "PT0.000042S");
+        assert_eq!(Duration::nanoseconds(42).to_string(), "PT0.000000042S");
         assert_eq!((Duration::days(7) + Duration::milliseconds(6543)).to_string(),
-                   "P7DT6.543S".to_string());
-        assert_eq!(Duration::seconds(-86401).to_string(), "-P1DT1S".to_string());
-        assert_eq!(Duration::nanoseconds(-1).to_string(), "-PT0.000000001S".to_string());
+                   "P7DT6.543S");
+        assert_eq!(Duration::seconds(-86401).to_string(), "-P1DT1S");
+        assert_eq!(Duration::nanoseconds(-1).to_string(), "-PT0.000000001S");
 
         // the format specifier should have no effect on `Duration`
         assert_eq!(format!("{:30}", Duration::days(1) + Duration::milliseconds(2345)),
-                   "P1DT2.345S".to_string());
+                   "P1DT2.345S");
     }
 }