Emit lint on literal for consistency and precise hint

Author: Artur-Sulej

clippy_lints/src/decimal_bit_mask.rs

@@ -1,5 +1,6 @@
 use clippy_utils::diagnostics::span_lint_and_help;
 use clippy_utils::source::SpanRangeExt;
+use rustc_ast::LitKind;
 use rustc_data_structures::packed::Pu128;
 use rustc_hir::{AssignOpKind, BinOpKind, Expr, ExprKind};
 use rustc_lint::{LateContext, LateLintPass};
@@ -42,11 +43,11 @@ fn check_bitwise_binary_expr(cx: &LateContext<'_>, e: &Expr<'_>) {
     ) = &e.kind
     {
         for expr in [left, right] {
-            if let ExprKind::Lit(_) = &expr.kind
-                && !is_not_decimal_number(cx, expr.span)
-                && !is_power_of_twoish(expr)
+            if let ExprKind::Lit(lit) = &expr.kind
+                && !is_not_decimal_number(cx, lit.span)
+                && !is_power_of_twoish(lit)
             {
-                emit_lint(cx, expr.span);
+                emit_lint(cx, lit.span);
             }
         }
     }
@@ -59,12 +60,12 @@ fn check_bitwise_assign_expr(cx: &LateContext<'_>, e: &Expr<'_>) {
             ..
         },
         _,
-        expr @ Expr {
+        Expr {
             kind: ExprKind::Lit(lit),
             ..
         },
     ) = &e.kind
-        && !is_power_of_twoish(expr)
+        && !is_power_of_twoish(lit)
         && !is_not_decimal_number(cx, lit.span)
     {
         emit_lint(cx, lit.span);
@@ -75,10 +76,8 @@ fn is_not_decimal_number(cx: &LateContext<'_>, span: Span) -> bool {
     span.check_source_text(cx, |src| src.contains("0b") || src.contains("0x") || src.contains("0o"))
 }
 
-fn is_power_of_twoish(expr: &Expr<'_>) -> bool {
-    if let ExprKind::Lit(lit) = &expr.kind
-        && let rustc_ast::LitKind::Int(Pu128(val), _) = lit.node
-    {
+fn is_power_of_twoish(lit: &Spanned<LitKind>) -> bool {
+    if let LitKind::Int(Pu128(val), _) = lit.node {
         return val.is_power_of_two() || val.wrapping_add(1).is_power_of_two();
     }
     false

tests/ui/decimal_bit_mask.rs

@@ -22,11 +22,11 @@ fn main() {
 
     // BAD: Bitwise operation, decimal literal, two literals
     0b1010 & 99; //~ decimal_bit_mask
-    0b1010 | 99; //~ decimal_bit_mask
-    0b1010 ^ 99; //~ decimal_bit_mask
+    0b1010 | (99); //~ decimal_bit_mask
+    0b1010 ^ (/* comment */99); //~ decimal_bit_mask
     99 & 0b1010; //~ decimal_bit_mask
-    99 | 0b1010; //~ decimal_bit_mask
-    99 ^ 0b1010; //~ decimal_bit_mask
+    (99) | 0b1010; //~ decimal_bit_mask
+    (/* comment */99) ^ 0b1010; //~ decimal_bit_mask
     0xD | 99; //~ decimal_bit_mask
     88 & 99;
     //~^ decimal_bit_mask
@@ -84,7 +84,7 @@ fn main() {
 
     // GOOD: Power of two and power of two minus one
     x & 16; // 2^4
-    x | 31; // 2^5 - 1
+    x | (31); // 2^5 - 1
     x ^ 0x40; // 2^6 (hex)
     x ^= 7; // 2^3 - 1
 

tests/ui/decimal_bit_mask.stderr

@@ -9,18 +9,18 @@ LL |     x & 99;
    = help: to override `-D warnings` add `#[allow(clippy::decimal_bit_mask)]`
 
 error: using decimal literal for bitwise operation
-  --> tests/ui/decimal_bit_mask.rs:17:9
+  --> tests/ui/decimal_bit_mask.rs:17:23
    |
 LL |     x | (/* comment */99);
-   |         ^^^^^^^^^^^^^^^^^
+   |                       ^^
    |
    = help: use binary (0b...) or hex (0x...) or octal (0o...) notation for better readability
 
 error: using decimal literal for bitwise operation
-  --> tests/ui/decimal_bit_mask.rs:18:9
+  --> tests/ui/decimal_bit_mask.rs:18:10
    |
 LL |     x ^ (99);
-   |         ^^^^
+   |          ^^
    |
    = help: use binary (0b...) or hex (0x...) or octal (0o...) notation for better readability
 
@@ -57,18 +57,18 @@ LL |     0b1010 & 99;
    = help: use binary (0b...) or hex (0x...) or octal (0o...) notation for better readability
 
 error: using decimal literal for bitwise operation
-  --> tests/ui/decimal_bit_mask.rs:25:14
+  --> tests/ui/decimal_bit_mask.rs:25:15
    |
-LL |     0b1010 | 99;
-   |              ^^
+LL |     0b1010 | (99);
+   |               ^^
    |
    = help: use binary (0b...) or hex (0x...) or octal (0o...) notation for better readability
 
 error: using decimal literal for bitwise operation
-  --> tests/ui/decimal_bit_mask.rs:26:14
+  --> tests/ui/decimal_bit_mask.rs:26:28
    |
-LL |     0b1010 ^ 99;
-   |              ^^
+LL |     0b1010 ^ (/* comment */99);
+   |                            ^^
    |
    = help: use binary (0b...) or hex (0x...) or octal (0o...) notation for better readability
 
@@ -81,18 +81,18 @@ LL |     99 & 0b1010;
    = help: use binary (0b...) or hex (0x...) or octal (0o...) notation for better readability
 
 error: using decimal literal for bitwise operation
-  --> tests/ui/decimal_bit_mask.rs:28:5
+  --> tests/ui/decimal_bit_mask.rs:28:6
    |
-LL |     99 | 0b1010;
-   |     ^^
+LL |     (99) | 0b1010;
+   |      ^^
    |
    = help: use binary (0b...) or hex (0x...) or octal (0o...) notation for better readability
 
 error: using decimal literal for bitwise operation
-  --> tests/ui/decimal_bit_mask.rs:29:5
+  --> tests/ui/decimal_bit_mask.rs:29:19
    |
-LL |     99 ^ 0b1010;
-   |     ^^
+LL |     (/* comment */99) ^ 0b1010;
+   |                   ^^
    |
    = help: use binary (0b...) or hex (0x...) or octal (0o...) notation for better readability