Use Self for recursive enums

Author: nickdrozd

clippy_lints/src/matches/single_match.rs

@@ -225,7 +225,7 @@ enum PatState<'a> {
     /// A std enum we know won't be extended. Tracks the states of each variant separately.
     ///
     /// This is not used for `Option` since it uses the current pattern to track it's state.
-    StdEnum(&'a mut [PatState<'a>]),
+    StdEnum(&'a mut [Self]),
     /// Either the initial state for a pattern or a non-std enum. There is currently no need to
     /// distinguish these cases.
     ///

clippy_utils/src/consts.rs

@@ -54,15 +54,15 @@ pub enum Constant<'tcx> {
     /// `true` or `false`.
     Bool(bool),
     /// An array of constants.
-    Vec(Vec<Constant<'tcx>>),
+    Vec(Vec<Self>),
     /// Also an array, but with only one constant, repeated N times.
-    Repeat(Box<Constant<'tcx>>, u64),
+    Repeat(Box<Self>, u64),
     /// A tuple of constants.
-    Tuple(Vec<Constant<'tcx>>),
+    Tuple(Vec<Self>),
     /// A raw pointer.
     RawPtr(u128),
     /// A reference
-    Ref(Box<Constant<'tcx>>),
+    Ref(Box<Self>),
     /// A literal with syntax error.
     Err,
 }

clippy_utils/src/sugg.rs

@@ -33,7 +33,7 @@ pub enum Sugg<'a> {
     /// or `-`, but only if the type with and without the operator is kept identical.
     /// It means that doubling the operator can be used to remove it instead, in
     /// order to provide better suggestions.
-    UnOp(UnOp, Box<Sugg<'a>>),
+    UnOp(UnOp, Box<Self>),
 }
 
 /// Literal constant `0`, for convenience.