Remove double spaces after dots in comments

compiler/rustc_data_structures/src/frozen.rs

@@ -36,7 +36,7 @@
 //! ```
 //!
 //! `Frozen` impls `Deref`, so we can ergonomically call methods on `Bar`, but it doesn't `impl
-//! DerefMut`.  Now calling `foo.compute.mutate()` will result in a compile-time error stating that
+//! DerefMut`. Now calling `foo.compute.mutate()` will result in a compile-time error stating that
 //! `mutate` requires a mutable reference but we don't have one.
 //!
 //! # Caveats

compiler/rustc_data_structures/src/graph/scc/tests.rs

@@ -84,7 +84,7 @@ fn test_find_state_2() {
     // 0 -> 1 -> 2 -> 1
     //
     // and at this point detect a cycle. The state of 2 will thus be
-    // `InCycleWith { 1 }`.  We will then visit the 1 -> 3 edge, which
+    // `InCycleWith { 1 }`. We will then visit the 1 -> 3 edge, which
     // will attempt to visit 0 as well, thus going to the state
     // `InCycleWith { 0 }`. Finally, node 1 will complete; the lowest
     // depth of any successor was 3 which had depth 0, and thus it

compiler/rustc_data_structures/src/transitive_relation.rs

@@ -250,7 +250,7 @@ impl<T: Eq + Hash + Copy> TransitiveRelation<T> {
             // values. So here is what we do:
             //
             // 1. Find the vector `[X | a < X && b < X]` of all values
-            //    `X` where `a < X` and `b < X`.  In terms of the
+            //    `X` where `a < X` and `b < X`. In terms of the
             //    graph, this means all values reachable from both `a`
             //    and `b`. Note that this vector is also a set, but we
             //    use the term vector because the order matters