Merge commit '0e87918536b9833bbc6c683d1f9d51ee2bf03ef1' into clippyup

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

diff --git a/clippy_lints/src/precedence.rs b/clippy_lints/src/precedence.rs
index 61c3cc37ae03e46f765da90ebdc84bb42669012a..9cf00c953b95f16afd34ec6e047f944d534c840e 100644 (file)
--- a/clippy_lints/src/precedence.rs
+++ b/clippy_lints/src/precedence.rs
@@ -1,11 +1,13 @@
-use crate::utils::{snippet_with_applicability, span_lint_and_sugg};
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::snippet_with_applicability;
+use if_chain::if_chain;
 use rustc_ast::ast::{BinOpKind, Expr, ExprKind, LitKind, UnOp};
 use rustc_errors::Applicability;
 use rustc_lint::{EarlyContext, EarlyLintPass};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 use rustc_span::source_map::Spanned;
 
-const ODD_FUNCTIONS_WHITELIST: [&str; 14] = [
+const ALLOWED_ODD_FUNCTIONS: [&str; 14] = [
     "asin",
     "asinh",
     "atan",
@@ -102,34 +104,36 @@ fn check_expr(&mut self, cx: &EarlyContext<'_>, expr: &Expr) {
             }
         }
 
-        if let ExprKind::Unary(UnOp::Neg, ref rhs) = expr.kind {
-            if let ExprKind::MethodCall(ref path_segment, ref args) = rhs.kind {
-                if let Some(slf) = args.first() {
-                    if let ExprKind::Lit(ref lit) = slf.kind {
-                        match lit.kind {
-                            LitKind::Int(..) | LitKind::Float(..) => {
-                                for &odd_function in &ODD_FUNCTIONS_WHITELIST {
-                                    if odd_function == &*path_segment.ident.name.as_str() {
-                                        return;
-                                    }
-                                }
-                                let mut applicability = Applicability::MachineApplicable;
-                                span_lint_and_sugg(
-                                    cx,
-                                    PRECEDENCE,
-                                    expr.span,
-                                    "unary minus has lower precedence than method call",
-                                    "consider adding parentheses to clarify your intent",
-                                    format!(
-                                        "-({})",
-                                        snippet_with_applicability(cx, rhs.span, "..", &mut applicability)
-                                    ),
-                                    applicability,
-                                );
-                            },
-                            _ => (),
-                        }
-                    }
+        if let ExprKind::Unary(UnOp::Neg, operand) = &expr.kind {
+            let mut arg = operand;
+
+            let mut all_odd = true;
+            while let ExprKind::MethodCall(path_segment, args, _) = &arg.kind {
+                let path_segment_str = path_segment.ident.name.as_str();
+                all_odd &= ALLOWED_ODD_FUNCTIONS
+                    .iter()
+                    .any(|odd_function| **odd_function == *path_segment_str);
+                arg = args.first().expect("A method always has a receiver.");
+            }
+
+            if_chain! {
+                if !all_odd;
+                if let ExprKind::Lit(lit) = &arg.kind;
+                if let LitKind::Int(..) | LitKind::Float(..) = &lit.kind;
+                then {
+                    let mut applicability = Applicability::MachineApplicable;
+                    span_lint_and_sugg(
+                        cx,
+                        PRECEDENCE,
+                        expr.span,
+                        "unary minus has lower precedence than method call",
+                        "consider adding parentheses to clarify your intent",
+                        format!(
+                            "-({})",
+                            snippet_with_applicability(cx, operand.span, "..", &mut applicability)
+                        ),
+                        applicability,
+                    );
                 }
             }
         }
@@ -146,17 +150,11 @@ fn is_arith_expr(expr: &Expr) -> bool {
 #[must_use]
 fn is_bit_op(op: BinOpKind) -> bool {
     use rustc_ast::ast::BinOpKind::{BitAnd, BitOr, BitXor, Shl, Shr};
-    match op {
-        BitXor | BitAnd | BitOr | Shl | Shr => true,
-        _ => false,
-    }
+    matches!(op, BitXor | BitAnd | BitOr | Shl | Shr)
 }
 
 #[must_use]
 fn is_arith_op(op: BinOpKind) -> bool {
     use rustc_ast::ast::BinOpKind::{Add, Div, Mul, Rem, Sub};
-    match op {
-        Add | Sub | Mul | Div | Rem => true,
-        _ => false,
-    }
+    matches!(op, Add | Sub | Mul | Div | Rem)
 }