Auto merge of #31911 - Manishearth:rollup, r=Manishearth

- Successful merges: #31878, #31880, #31883, #31893, #31894, #31896, #31901, #31904
- Failed merges: #31897

3 files changed, 14 insertions, 11 deletions

diff --git a/src/libstd/env.rs b/src/libstd/env.rs
index aa6a6d548b3..3a543a947b5 100644
--- a/src/libstd/env.rs
+++ b/src/libstd/env.rs
@@ -442,7 +442,7 @@ impl Error for JoinPathsError {
 ///
 /// match env::home_dir() {
 ///     Some(ref p) => println!("{}", p.display()),
-///     None => println!("Impossible to get your home dir!")
+///     None => println!("Impossible to get your home dir!"),
 /// }
 /// ```
 #[stable(feature = "env", since = "1.0.0")]
@@ -482,8 +482,7 @@ pub fn temp_dir() -> PathBuf {
     os_imp::temp_dir()
 }
 
-/// Returns the filesystem path to the current executable which is running but
-/// with the executable name.
+/// Returns the full filesystem path to the current running executable.
 ///
 /// The path returned is not necessarily a "real path" to the executable as
 /// there may be intermediate symlinks.
@@ -492,7 +491,7 @@ pub fn temp_dir() -> PathBuf {
 ///
 /// Acquiring the path to the current executable is a platform-specific operation
 /// that can fail for a good number of reasons. Some errors can include, but not
-/// be limited to filesystem operations failing or general syscall failures.
+/// be limited to, filesystem operations failing or general syscall failures.
 ///
 /// # Examples
 ///
diff --git a/src/libstd/io/mod.rs b/src/libstd/io/mod.rs
index 6bdfdcd364a..61334f30924 100644
--- a/src/libstd/io/mod.rs
+++ b/src/libstd/io/mod.rs
@@ -1055,7 +1055,14 @@ pub trait Write {
         let mut output = Adaptor { inner: self, error: Ok(()) };
         match fmt::write(&mut output, fmt) {
             Ok(()) => Ok(()),
-            Err(..) => output.error
+            Err(..) => {
+                // check if the error came from the underlying `Write` or not
+                if output.error.is_err() {
+                    output.error
+                } else {
+                    Err(Error::new(ErrorKind::Other, "formatter error"))
+                }
+            }
         }
     }
 
diff --git a/src/libstd/path.rs b/src/libstd/path.rs
index 35118bde96b..94967bfb96a 100644
--- a/src/libstd/path.rs
+++ b/src/libstd/path.rs
@@ -226,7 +226,7 @@ mod platform {
                     }
                     _ => (),
                 }
-            } else if path.len() > 1 && path[1] == b':' {
+            } else if path.get(1) == Some(& b':') {
                 // C:
                 let c = path[0];
                 if c.is_ascii() && (c as char).is_alphabetic() {
@@ -393,11 +393,8 @@ fn iter_after<A, I, J>(mut iter: I, mut prefix: J) -> Option<I>
     loop {
         let mut iter_next = iter.clone();
         match (iter_next.next(), prefix.next()) {
-            (Some(x), Some(y)) => {
-                if x != y {
-                    return None;
-                }
-            }
+            (Some(ref x), Some(ref y)) if x == y => (),
+            (Some(_), Some(_)) => return None,
             (Some(_), None) => return Some(iter),
             (None, None) => return Some(iter),
             (None, Some(_)) => return None,