Auto merge of #67540 - Mark-Simulacrum:fmt-the-world, r=Centril

Format the world

This PR modifies the formatting infrastructure a bit in the first commit (to enable the forgotten 2018 edition), as well as removes most directories from the ignore list in rustfmt.toml. It then follows that up with the second commit which runs `x.py fmt` and formats the entire repository.

We continue to not format the test directory (`src/test`) because of interactions with pretty printing and, in part, because re-blessing all of those files is somewhat harder to review, so is best suited for a follow up PR in my opinion.

1 files changed, 12 insertions, 9 deletions

diff --git a/src/libcore/array/mod.rs b/src/libcore/array/mod.rs
index fd80000b6fb..937451274cf 100644
--- a/src/libcore/array/mod.rs
+++ b/src/libcore/array/mod.rs
@@ -10,7 +10,7 @@ use crate::borrow::{Borrow, BorrowMut};
 use crate::cmp::Ordering;
 use crate::convert::{Infallible, TryFrom};
 use crate::fmt;
-use crate::hash::{Hash, self};
+use crate::hash::{self, Hash};
 use crate::marker::Unsize;
 use crate::slice::{Iter, IterMut};
 
@@ -71,10 +71,12 @@ impl fmt::Display for TryFromSliceError {
 }
 
 impl TryFromSliceError {
-    #[unstable(feature = "array_error_internals",
-           reason = "available through Error trait and this method should not \
+    #[unstable(
+        feature = "array_error_internals",
+        reason = "available through Error trait and this method should not \
                      be exposed publicly",
-           issue = "none")]
+        issue = "none"
+    )]
     #[inline]
     #[doc(hidden)]
     pub fn __description(&self) -> &str {
@@ -385,11 +387,12 @@ where
 }
 
 /// Implemented for lengths where trait impls are allowed on arrays in core/std
-#[rustc_on_unimplemented(
-    message="arrays only have std trait implementations for lengths 0..=32",
+#[rustc_on_unimplemented(message = "arrays only have std trait implementations for lengths 0..=32")]
+#[unstable(
+    feature = "const_generic_impls_guard",
+    issue = "none",
+    reason = "will never be stable, just a temporary step until const generics are stable"
 )]
-#[unstable(feature = "const_generic_impls_guard", issue = "none",
-    reason = "will never be stable, just a temporary step until const generics are stable")]
 pub trait LengthAtMost32 {}
 
 macro_rules! array_impls {
@@ -429,4 +432,4 @@ macro_rules! array_impl_default {
     };
 }
 
-array_impl_default!{32, T T T T T T T T T T T T T T T T T T T T T T T T T T T T T T T T}
+array_impl_default! {32, T T T T T T T T T T T T T T T T T T T T T T T T T T T T T T T T}