Auto merge of #9148 - arieluy:then_some_unwrap_or, r=Jarcho

[rust.git] / clippy_lints / src / comparison_chain.rs

diff --git a/clippy_lints/src/comparison_chain.rs b/clippy_lints/src/comparison_chain.rs
index d601cb7c22473ca561c059be8d29e1fda99e8735..a05b41eb3ab52f72441b53a75dcadfdfa167b1e6 100644 (file)
--- a/clippy_lints/src/comparison_chain.rs
+++ b/clippy_lints/src/comparison_chain.rs
@@ -1,21 +1,24 @@
 use clippy_utils::diagnostics::span_lint_and_help;
 use clippy_utils::ty::implements_trait;
-use clippy_utils::{get_trait_def_id, if_sequence, parent_node_is_if_expr, paths, SpanlessEq};
+use clippy_utils::{get_trait_def_id, if_sequence, in_constant, is_else_clause, paths, SpanlessEq};
 use rustc_hir::{BinOpKind, Expr, ExprKind};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 
 declare_clippy_lint! {
-    /// **What it does:** Checks comparison chains written with `if` that can be
+    /// ### What it does
+    /// Checks comparison chains written with `if` that can be
     /// rewritten with `match` and `cmp`.
     ///
-    /// **Why is this bad?** `if` is not guaranteed to be exhaustive and conditionals can get
+    /// ### Why is this bad?
+    /// `if` is not guaranteed to be exhaustive and conditionals can get
     /// repetitive
     ///
-    /// **Known problems:** The match statement may be slower due to the compiler
+    /// ### Known problems
+    /// The match statement may be slower due to the compiler
     /// not inlining the call to cmp. See issue [#5354](https://github.com/rust-lang/rust-clippy/issues/5354)
     ///
-    /// **Example:**
+    /// ### Example
     /// ```rust,ignore
     /// # fn a() {}
     /// # fn b() {}
@@ -31,8 +34,7 @@
     /// }
     /// ```
     ///
-    /// Could be written:
-    ///
+    /// Use instead:
     /// ```rust,ignore
     /// use std::cmp::Ordering;
     /// # fn a() {}
@@ -46,6 +48,7 @@
     ///      }
     /// }
     /// ```
+    #[clippy::version = "1.40.0"]
     pub COMPARISON_CHAIN,
     style,
     "`if`s that can be rewritten with `match` and `cmp`"
@@ -60,7 +63,11 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
         }
 
         // We only care about the top-most `if` in the chain
-        if parent_node_is_if_expr(expr, cx) {
+        if is_else_clause(cx.tcx, expr) {
+            return;
+        }
+
+        if in_constant(cx, expr.hir_id) {
             return;
         }
 
@@ -71,10 +78,8 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
         }
 
         for cond in conds.windows(2) {
-            if let (
-                &ExprKind::Binary(ref kind1, ref lhs1, ref rhs1),
-                &ExprKind::Binary(ref kind2, ref lhs2, ref rhs2),
-            ) = (&cond[0].kind, &cond[1].kind)
+            if let (&ExprKind::Binary(ref kind1, lhs1, rhs1), &ExprKind::Binary(ref kind2, lhs2, rhs2)) =
+                (&cond[0].kind, &cond[1].kind)
             {
                 if !kind_is_cmp(kind1.node) || !kind_is_cmp(kind2.node) {
                     return;
@@ -118,7 +123,7 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
             "`if` chain can be rewritten with `match`",
             None,
             "consider rewriting the `if` chain to use `cmp` and `match`",
-        )
+        );
     }
 }