Rename HIR UnOp variants

This renames the variants in HIR UnOp from

    enum UnOp {
        UnDeref,
        UnNot,
        UnNeg,
    }

to

    enum UnOp {
        Deref,
        Not,
        Neg,
    }

Motivations:

- This is more consistent with the rest of the code base where most enum
  variants don't have a prefix.

- These variants are never used without the `UnOp` prefix so the extra
  `Un` prefix doesn't help with readability. E.g. we don't have any
  `UnDeref`s in the code, we only have `UnOp::UnDeref`.

- MIR `UnOp` type variants don't have a prefix so this is more
  consistent with MIR types.

- "un" prefix reads like "inverse" or "reverse", so as a beginner in
  rustc code base when I see "UnDeref" what comes to my mind is
  something like "&*" instead of just "*".

clippy_lints/src/arithmetic.rs

@@ -91,7 +91,7 @@ impl<'tcx> LateLintPass<'tcx> for Arithmetic {
                     match op.node {
                         hir::BinOpKind::Div | hir::BinOpKind::Rem => match &r.kind {
                             hir::ExprKind::Lit(_lit) => (),
-                            hir::ExprKind::Unary(hir::UnOp::UnNeg, expr) => {
+                            hir::ExprKind::Unary(hir::UnOp::Neg, expr) => {
                                 if let hir::ExprKind::Lit(lit) = &expr.kind {
                                     if let rustc_ast::ast::LitKind::Int(1, _) = lit.node {
                                         span_lint(cx, INTEGER_ARITHMETIC, expr.span, "integer arithmetic detected");
@@ -114,7 +114,7 @@ impl<'tcx> LateLintPass<'tcx> for Arithmetic {
                     self.expr_span = Some(expr.span);
                 }
             },
-            hir::ExprKind::Unary(hir::UnOp::UnNeg, arg) => {
+            hir::ExprKind::Unary(hir::UnOp::Neg, arg) => {
                 let ty = cx.typeck_results().expr_ty(arg);
                 if constant_simple(cx, cx.typeck_results(), expr).is_none() {
                     if ty.is_integral() {

clippy_lints/src/assertions_on_constants.rs

@@ -112,7 +112,7 @@ enum AssertKind {
 fn match_assert_with_message<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) -> Option<AssertKind> {
     if_chain! {
         if let ExprKind::If(ref cond, ref then, _) = expr.kind;
-        if let ExprKind::Unary(UnOp::UnNot, ref expr) = cond.kind;
+        if let ExprKind::Unary(UnOp::Not, ref expr) = cond.kind;
         // bind the first argument of the `assert!` macro
         if let Some((Constant::Bool(is_true), _)) = constant(cx, cx.typeck_results(), expr);
         // block

clippy_lints/src/booleans.rs

@@ -110,7 +110,7 @@ impl<'a, 'tcx, 'v> Hir2Qmm<'a, 'tcx, 'v> {
         // prevent folding of `cfg!` macros and the like
         if !e.span.from_expansion() {
             match &e.kind {
-                ExprKind::Unary(UnOp::UnNot, inner) => return Ok(Bool::Not(box self.run(inner)?)),
+                ExprKind::Unary(UnOp::Not, inner) => return Ok(Bool::Not(box self.run(inner)?)),
                 ExprKind::Binary(binop, lhs, rhs) => match &binop.node {
                     BinOpKind::Or => {
                         return Ok(Bool::Or(self.extract(BinOpKind::Or, &[lhs, rhs], Vec::new())?));
@@ -454,7 +454,7 @@ impl<'a, 'tcx> Visitor<'tcx> for NonminimalBoolVisitor<'a, 'tcx> {
             ExprKind::Binary(binop, _, _) if binop.node == BinOpKind::Or || binop.node == BinOpKind::And => {
                 self.bool_expr(e)
             },
-            ExprKind::Unary(UnOp::UnNot, inner) => {
+            ExprKind::Unary(UnOp::Not, inner) => {
                 if self.cx.typeck_results().node_types()[inner.hir_id].is_bool() {
                     self.bool_expr(e);
                 } else {
@@ -482,7 +482,7 @@ impl<'a, 'tcx> Visitor<'tcx> for NotSimplificationVisitor<'a, 'tcx> {
     type Map = Map<'tcx>;
 
     fn visit_expr(&mut self, expr: &'tcx Expr<'_>) {
-        if let ExprKind::Unary(UnOp::UnNot, inner) = &expr.kind {
+        if let ExprKind::Unary(UnOp::Not, inner) = &expr.kind {
             if let Some(suggestion) = simplify_not(self.cx, inner) {
                 span_lint_and_sugg(
                     self.cx,

clippy_lints/src/bytecount.rs

@@ -101,7 +101,7 @@ fn check_arg(name: Symbol, arg: Symbol, needle: &Expr<'_>) -> bool {
 
 fn get_path_name(expr: &Expr<'_>) -> Option<Symbol> {
     match expr.kind {
-        ExprKind::Box(ref e) | ExprKind::AddrOf(BorrowKind::Ref, _, ref e) | ExprKind::Unary(UnOp::UnDeref, ref e) => {
+        ExprKind::Box(ref e) | ExprKind::AddrOf(BorrowKind::Ref, _, ref e) | ExprKind::Unary(UnOp::Deref, ref e) => {
             get_path_name(e)
         },
         ExprKind::Block(ref b, _) => {

clippy_lints/src/collapsible_match.rs

@@ -186,7 +186,7 @@ fn addr_adjusted_binding(mut expr: &Expr<'_>, cx: &LateContext<'_>) -> Option<Hi
                 Res::Local(binding_id) => break Some(binding_id),
                 _ => break None,
             },
-            ExprKind::Unary(UnOp::UnDeref, e) if cx.typeck_results().expr_ty(e).is_ref() => expr = e,
+            ExprKind::Unary(UnOp::Deref, e) if cx.typeck_results().expr_ty(e).is_ref() => expr = e,
             _ => break None,
         }
     }

clippy_lints/src/consts.rs

@@ -242,9 +242,9 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
                 self.expr(value).map(|v| Constant::Repeat(Box::new(v), n))
             },
             ExprKind::Unary(op, ref operand) => self.expr(operand).and_then(|o| match op {
-                UnOp::UnNot => self.constant_not(&o, self.typeck_results.expr_ty(e)),
-                UnOp::UnNeg => self.constant_negate(&o, self.typeck_results.expr_ty(e)),
-                UnOp::UnDeref => Some(if let Constant::Ref(r) = o { *r } else { o }),
+                UnOp::Not => self.constant_not(&o, self.typeck_results.expr_ty(e)),
+                UnOp::Neg => self.constant_negate(&o, self.typeck_results.expr_ty(e)),
+                UnOp::Deref => Some(if let Constant::Ref(r) = o { *r } else { o }),
             }),
             ExprKind::If(ref cond, ref then, ref otherwise) => self.ifthenelse(cond, then, *otherwise),
             ExprKind::Binary(op, ref left, ref right) => self.binop(op, left, right),

clippy_lints/src/entry.rs

@@ -55,7 +55,7 @@ declare_lint_pass!(HashMapPass => [MAP_ENTRY]);
 impl<'tcx> LateLintPass<'tcx> for HashMapPass {
     fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
         if let ExprKind::If(ref check, ref then_block, ref else_block) = expr.kind {
-            if let ExprKind::Unary(UnOp::UnNot, ref check) = check.kind {
+            if let ExprKind::Unary(UnOp::Not, ref check) = check.kind {
                 if let Some((ty, map, key)) = check_cond(cx, check) {
                     // in case of `if !m.contains_key(&k) { m.insert(k, v); }`
                     // we can give a better error message

clippy_lints/src/floating_point_arithmetic.rs

@@ -129,7 +129,7 @@ fn get_specialized_log_method(cx: &LateContext<'_>, base: &Expr<'_>) -> Option<&
 fn prepare_receiver_sugg<'a>(cx: &LateContext<'_>, mut expr: &'a Expr<'a>) -> Sugg<'a> {
     let mut suggestion = Sugg::hir(cx, expr, "..");
 
-    if let ExprKind::Unary(UnOp::UnNeg, inner_expr) = &expr.kind {
+    if let ExprKind::Unary(UnOp::Neg, inner_expr) = &expr.kind {
         expr = &inner_expr;
     }
 
@@ -541,12 +541,12 @@ fn is_zero(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
 /// If the two expressions are not negations of each other, then it
 /// returns None.
 fn are_negated<'a>(cx: &LateContext<'_>, expr1: &'a Expr<'a>, expr2: &'a Expr<'a>) -> Option<(bool, &'a Expr<'a>)> {
-    if let ExprKind::Unary(UnOp::UnNeg, expr1_negated) = &expr1.kind {
+    if let ExprKind::Unary(UnOp::Neg, expr1_negated) = &expr1.kind {
         if eq_expr_value(cx, expr1_negated, expr2) {
             return Some((false, expr2));
         }
     }
-    if let ExprKind::Unary(UnOp::UnNeg, expr2_negated) = &expr2.kind {
+    if let ExprKind::Unary(UnOp::Neg, expr2_negated) = &expr2.kind {
         if eq_expr_value(cx, expr1, expr2_negated) {
             return Some((true, expr1));
         }

clippy_lints/src/functions.rs

@@ -644,7 +644,7 @@ impl<'a, 'tcx> intravisit::Visitor<'tcx> for DerefVisitor<'a, 'tcx> {
                     }
                 }
             },
-            hir::ExprKind::Unary(hir::UnOp::UnDeref, ref ptr) => self.check_arg(ptr),
+            hir::ExprKind::Unary(hir::UnOp::Deref, ref ptr) => self.check_arg(ptr),
             _ => (),
         }
 

clippy_lints/src/map_clone.rs

@@ -70,7 +70,7 @@ impl<'tcx> LateLintPass<'tcx> for MapClone {
                     },
                     hir::PatKind::Binding(hir::BindingAnnotation::Unannotated, .., name, None) => {
                         match closure_expr.kind {
-                            hir::ExprKind::Unary(hir::UnOp::UnDeref, ref inner) => {
+                            hir::ExprKind::Unary(hir::UnOp::Deref, ref inner) => {
                                 if ident_eq(name, inner) {
                                     if let ty::Ref(.., Mutability::Not) = cx.typeck_results().expr_ty(inner).kind() {
                                         lint(cx, e.span, args[0].span, true);

clippy_lints/src/methods/manual_saturating_arithmetic.rs

@@ -148,7 +148,7 @@ fn is_min_or_max<'tcx>(cx: &LateContext<'tcx>, expr: &hir::Expr<'_>) -> Option<M
     }
 
     if ty.is_signed() {
-        if let hir::ExprKind::Unary(hir::UnOp::UnNeg, val) = &expr.kind {
+        if let hir::ExprKind::Unary(hir::UnOp::Neg, val) = &expr.kind {
             return check_lit(val, true);
         }
     }
@@ -163,7 +163,7 @@ enum Sign {
 }
 
 fn lit_sign(expr: &hir::Expr<'_>) -> Option<Sign> {
-    if let hir::ExprKind::Unary(hir::UnOp::UnNeg, inner) = &expr.kind {
+    if let hir::ExprKind::Unary(hir::UnOp::Neg, inner) = &expr.kind {
         if let hir::ExprKind::Lit(..) = &inner.kind {
             return Some(Sign::Neg);
         }

clippy_lints/src/methods/mod.rs

@@ -2619,7 +2619,7 @@ fn lint_get_unwrap<'tcx>(cx: &LateContext<'tcx>, expr: &hir::Expr<'_>, get_args:
     if_chain! {
         if needs_ref;
         if let Some(parent) = get_parent_expr(cx, expr);
-        if let hir::ExprKind::Unary(hir::UnOp::UnDeref, _) = parent.kind;
+        if let hir::ExprKind::Unary(hir::UnOp::Deref, _) = parent.kind;
         then {
             needs_ref = false;
             span = parent.span;
@@ -3063,7 +3063,7 @@ fn lint_filter_map<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>, is_f
             // in `filter(|x| ..)`, replace `*x` with `x`
             let a_path = if_chain! {
                 if !is_filter_param_ref;
-                if let ExprKind::Unary(UnOp::UnDeref, expr_path) = a.kind;
+                if let ExprKind::Unary(UnOp::Deref, expr_path) = a.kind;
                 then { expr_path } else { a }
             };
             // let the filter closure arg and the map closure arg be equal
@@ -3708,8 +3708,8 @@ fn lint_option_as_ref_deref<'tcx>(
                 },
                 hir::ExprKind::AddrOf(hir::BorrowKind::Ref, m, ref inner) if same_mutability(m) => {
                     if_chain! {
-                        if let hir::ExprKind::Unary(hir::UnOp::UnDeref, ref inner1) = inner.kind;
-                        if let hir::ExprKind::Unary(hir::UnOp::UnDeref, ref inner2) = inner1.kind;
+                        if let hir::ExprKind::Unary(hir::UnOp::Deref, ref inner1) = inner.kind;
+                        if let hir::ExprKind::Unary(hir::UnOp::Deref, ref inner2) = inner1.kind;
                         if let hir::ExprKind::Path(ref qpath) = inner2.kind;
                         if let hir::def::Res::Local(local_id) = cx.qpath_res(qpath, inner2.hir_id);
                         then {
@@ -4065,7 +4065,7 @@ fn lint_filetype_is_file(cx: &LateContext<'_>, expr: &hir::Expr<'_>, args: &[hir
     if_chain! {
         if let Some(parent) = get_parent_expr(cx, expr);
         if let hir::ExprKind::Unary(op, _) = parent.kind;
-        if op == hir::UnOp::UnNot;
+        if op == hir::UnOp::Not;
         then {
             lint_unary = "!";
             verb = "denies";

clippy_lints/src/misc.rs

@@ -502,7 +502,7 @@ fn is_allowed<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) -> bool {
 // Return true if `expr` is the result of `signum()` invoked on a float value.
 fn is_signum(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
     // The negation of a signum is still a signum
-    if let ExprKind::Unary(UnOp::UnNeg, ref child_expr) = expr.kind {
+    if let ExprKind::Unary(UnOp::Neg, ref child_expr) = expr.kind {
         return is_signum(cx, &child_expr);
     }
 
@@ -586,7 +586,7 @@ fn check_to_owned(cx: &LateContext<'_>, expr: &Expr<'_>, other: &Expr<'_>, left:
         return;
     }
 
-    let other_gets_derefed = matches!(other.kind, ExprKind::Unary(UnOp::UnDeref, _));
+    let other_gets_derefed = matches!(other.kind, ExprKind::Unary(UnOp::Deref, _));
 
     let lint_span = if other_gets_derefed {
         expr.span.to(other.span)

clippy_lints/src/needless_bool.rs

@@ -195,7 +195,7 @@ struct ExpressionInfoWithSpan {
 }
 
 fn is_unary_not(e: &Expr<'_>) -> (bool, Span) {
-    if let ExprKind::Unary(UnOp::UnNot, operand) = e.kind {
+    if let ExprKind::Unary(UnOp::Not, operand) = e.kind {
         return (true, operand.span);
     }
     (false, e.span)

clippy_lints/src/neg_cmp_op_on_partial_ord.rs

@@ -50,7 +50,7 @@ impl<'tcx> LateLintPass<'tcx> for NoNegCompOpForPartialOrd {
         if_chain! {
 
             if !in_external_macro(cx.sess(), expr.span);
-            if let ExprKind::Unary(UnOp::UnNot, ref inner) = expr.kind;
+            if let ExprKind::Unary(UnOp::Not, ref inner) = expr.kind;
             if let ExprKind::Binary(ref op, ref left, _) = inner.kind;
             if let BinOpKind::Le | BinOpKind::Ge | BinOpKind::Lt | BinOpKind::Gt = op.node;
 

clippy_lints/src/neg_multiply.rs

@@ -32,8 +32,8 @@ impl<'tcx> LateLintPass<'tcx> for NegMultiply {
             if BinOpKind::Mul == op.node {
                 match (&left.kind, &right.kind) {
                     (&ExprKind::Unary(..), &ExprKind::Unary(..)) => {},
-                    (&ExprKind::Unary(UnOp::UnNeg, ref lit), _) => check_mul(cx, e.span, lit, right),
-                    (_, &ExprKind::Unary(UnOp::UnNeg, ref lit)) => check_mul(cx, e.span, lit, left),
+                    (&ExprKind::Unary(UnOp::Neg, ref lit), _) => check_mul(cx, e.span, lit, right),
+                    (_, &ExprKind::Unary(UnOp::Neg, ref lit)) => check_mul(cx, e.span, lit, left),
                     _ => {},
                 }
             }

clippy_lints/src/non_copy_const.rs

@@ -383,7 +383,7 @@ impl<'tcx> LateLintPass<'tcx> for NonCopyConst {
                             needs_check_adjustment = false;
                             break;
                         },
-                        ExprKind::Unary(UnOp::UnDeref, _) => {
+                        ExprKind::Unary(UnOp::Deref, _) => {
                             // `*e` => desugared to `*Deref::deref(&e)`,
                             // meaning `e` must be referenced.
                             // no need to go further up since a method call is involved now.

clippy_lints/src/option_if_let_else.rs

@@ -181,7 +181,7 @@ fn detect_option_if_let_else<'tcx>(
             };
             let cond_expr = match &cond_expr.kind {
                 // Pointer dereferencing happens automatically, so we can omit it in the suggestion
-                ExprKind::Unary(UnOp::UnDeref, expr) | ExprKind::AddrOf(_, _, expr) => expr,
+                ExprKind::Unary(UnOp::Deref, expr) | ExprKind::AddrOf(_, _, expr) => expr,
                 _ => cond_expr,
             };
             Some(OptionIfLetElseOccurence {

clippy_lints/src/shadow.rs

@@ -389,7 +389,7 @@ fn is_self_shadow(name: Symbol, expr: &Expr<'_>) -> bool {
         ExprKind::Block(ref block, _) => {
             block.stmts.is_empty() && block.expr.as_ref().map_or(false, |e| is_self_shadow(name, e))
         },
-        ExprKind::Unary(op, ref inner) => (UnOp::UnDeref == op) && is_self_shadow(name, inner),
+        ExprKind::Unary(op, ref inner) => (UnOp::Deref == op) && is_self_shadow(name, inner),
         ExprKind::Path(QPath::Resolved(_, ref path)) => path_eq_name(name, path),
         _ => false,
     }

clippy_lints/src/suspicious_trait_impl.rs

@@ -194,7 +194,7 @@ impl<'tcx> Visitor<'tcx> for BinaryExprVisitor {
     fn visit_expr(&mut self, expr: &'tcx hir::Expr<'_>) {
         match expr.kind {
             hir::ExprKind::Binary(..)
-            | hir::ExprKind::Unary(hir::UnOp::UnNot | hir::UnOp::UnNeg, _)
+            | hir::ExprKind::Unary(hir::UnOp::Not | hir::UnOp::Neg, _)
             | hir::ExprKind::AssignOp(..) => self.nb_binops += 1,
             _ => {},
         }

clippy_lints/src/transmute.rs

@@ -586,7 +586,7 @@ impl<'tcx> LateLintPass<'tcx> for Transmute {
                             let mut expr = &args[0];
                             let mut arg = sugg::Sugg::hir(cx, expr, "..");
 
-                            if let ExprKind::Unary(UnOp::UnNeg, inner_expr) = &expr.kind {
+                            if let ExprKind::Unary(UnOp::Neg, inner_expr) = &expr.kind {
                                 expr = &inner_expr;
                             }
 

clippy_lints/src/types.rs

@@ -1706,13 +1706,13 @@ impl<'tcx> LateLintPass<'tcx> for Casts {
 }
 
 fn is_unary_neg(expr: &Expr<'_>) -> bool {
-    matches!(expr.kind, ExprKind::Unary(UnOp::UnNeg, _))
+    matches!(expr.kind, ExprKind::Unary(UnOp::Neg, _))
 }
 
 fn get_numeric_literal<'e>(expr: &'e Expr<'e>) -> Option<&'e Lit> {
     match expr.kind {
         ExprKind::Lit(ref lit) => Some(lit),
-        ExprKind::Unary(UnOp::UnNeg, e) => {
+        ExprKind::Unary(UnOp::Neg, e) => {
             if let ExprKind::Lit(ref lit) = e.kind {
                 Some(lit)
             } else {
@@ -2868,7 +2868,7 @@ declare_lint_pass!(RefToMut => [CAST_REF_TO_MUT]);
 impl<'tcx> LateLintPass<'tcx> for RefToMut {
     fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
         if_chain! {
-            if let ExprKind::Unary(UnOp::UnDeref, e) = &expr.kind;
+            if let ExprKind::Unary(UnOp::Deref, e) = &expr.kind;
             if let ExprKind::Cast(e, t) = &e.kind;
             if let TyKind::Ptr(MutTy { mutbl: Mutability::Mut, .. }) = t.kind;
             if let ExprKind::Cast(e, t) = &e.kind;

clippy_lints/src/unwrap.rs

@@ -108,7 +108,7 @@ fn collect_unwrap_info<'tcx>(
             },
             _ => (),
         }
-    } else if let ExprKind::Unary(UnOp::UnNot, expr) = &expr.kind {
+    } else if let ExprKind::Unary(UnOp::Not, expr) = &expr.kind {
         return collect_unwrap_info(cx, expr, branch, !invert);
     } else {
         if_chain! {

clippy_lints/src/utils/higher.rs

@@ -243,7 +243,7 @@ pub fn extract_assert_macro_args<'tcx>(e: &'tcx Expr<'tcx>) -> Option<Vec<&'tcx
                 // macros with unique arg: `{debug_}assert!` (e.g., `debug_assert!(some_condition)`)
                 if_chain! {
                     if let ExprKind::If(ref clause, _, _)  = matchexpr.kind;
-                    if let ExprKind::Unary(UnOp::UnNot, condition) = clause.kind;
+                    if let ExprKind::Unary(UnOp::Not, condition) = clause.kind;
                     then {
                         return Some(vec![condition]);
                     }

clippy_lints/src/utils/internal_lints.rs

@@ -1001,7 +1001,7 @@ impl InterningDefinedSymbol {
         // SymbolStr might be de-referenced: `&*symbol.as_str()`
         let call = if_chain! {
             if let ExprKind::AddrOf(_, _, e) = expr.kind;
-            if let ExprKind::Unary(UnOp::UnDeref, e) = e.kind;
+            if let ExprKind::Unary(UnOp::Deref, e) = e.kind;
             then { e } else { expr }
         };
         if_chain! {

tests/ui/suspicious_arithmetic_impl.rs

@@ -117,7 +117,7 @@ impl Add for Bar {
     type Output = Bar;
 
     fn add(self, other: Self) -> Self {
-        Bar(self.0 & !other.0) // OK: UnNot part of BiExpr as child node
+        Bar(self.0 & !other.0) // OK: Not part of BiExpr as child node
     }
 }
 
@@ -126,7 +126,7 @@ impl Sub for Bar {
 
     fn sub(self, other: Self) -> Self {
         if self.0 <= other.0 {
-            Bar(-(self.0 & other.0)) // OK: UnNeg part of BiExpr as parent node
+            Bar(-(self.0 & other.0)) // OK: Neg part of BiExpr as parent node
         } else {
             Bar(0)
         }