Merge #3370

3370: bool_comparison triggers 3 times on same code r=phansch a=mrbuzz

Fix #3335 

Co-authored-by: Giorgio Gambino <gambnio.giorgio@gmail.com>

Author: bors[bot]

clippy_lints/src/needless_bool.rs

@@ -17,7 +17,7 @@ use crate::rustc::{declare_tool_lint, lint_array};
 use crate::rustc::hir::*;
 use crate::syntax::ast::LitKind;
 use crate::syntax::source_map::Spanned;
-use crate::utils::{snippet, span_lint, span_lint_and_sugg};
+use crate::utils::{in_macro, snippet, span_lint, span_lint_and_sugg};
 use crate::utils::sugg::Sugg;
 
 /// **What it does:** Checks for expressions of the form `if c { true } else {
@@ -133,6 +133,9 @@ impl LintPass for BoolComparison {
 
 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for BoolComparison {
     fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, e: &'tcx Expr) {
+        if in_macro(e.span) {
+            return;
+        }
         use self::Expression::*;
         if let ExprKind::Binary(Spanned { node: BinOpKind::Eq, .. }, ref left_side, ref right_side) = e.node {
             match (fetch_bool_expr(left_side), fetch_bool_expr(right_side)) {

tests/ui/needless_bool.rs

@@ -8,9 +8,31 @@
 // except according to those terms.
 
 
+#![warn(clippy::needless_bool)]
 
+use std::cell::Cell;
 
-#![warn(clippy::needless_bool)]
+macro_rules! bool_comparison_trigger {
+    ($($i:ident: $def:expr, $stb:expr );+  $(;)*) => (
+
+        #[derive(Clone)]
+        pub struct Trigger {
+            $($i: (Cell<bool>, bool, bool)),+
+        }
+
+        #[allow(dead_code)]
+        impl Trigger {
+            pub fn trigger(&self, key: &str) -> bool {
+                $(
+                    if let stringify!($i) = key {
+                        return self.$i.1 && self.$i.2 == $def;
+                    }
+                 )+
+                false
+            }
+        }
+    )
+}
 
 #[allow(clippy::if_same_then_else)]
 fn main() {
@@ -28,6 +50,9 @@ fn main() {
     bool_ret5(x, x);
     bool_ret4(x);
     bool_ret6(x, x);
+    needless_bool(x);
+    needless_bool2(x);
+    needless_bool3(x);
 }
 
 #[allow(clippy::if_same_then_else, clippy::needless_return)]
@@ -59,3 +84,23 @@ fn bool_ret4(x: bool) -> bool {
 fn bool_ret6(x: bool, y: bool) -> bool {
     if x && y { return false } else { return true };
 }
+
+fn needless_bool(x: bool) {
+   if x  == true { };
+}
+
+fn needless_bool2(x: bool) {
+   if x  == false { };
+}
+
+fn needless_bool3(x: bool) {
+    
+    bool_comparison_trigger! {
+        test_one:   false, false;
+        test_three: false, false;
+        test_two:   true, true;
+    }
+    
+    if x == true { };
+    if x == false { };
+}

tests/ui/needless_bool.stderr

@@ -1,70 +1,96 @@
 error: this if-then-else expression will always return true
-  --> $DIR/needless_bool.rs:19:5
+  --> $DIR/needless_bool.rs:41:5
    |
-19 |     if x { true } else { true };
+41 |     if x { true } else { true };
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: `-D clippy::needless-bool` implied by `-D warnings`
 
 error: this if-then-else expression will always return false
-  --> $DIR/needless_bool.rs:20:5
+  --> $DIR/needless_bool.rs:42:5
    |
-20 |     if x { false } else { false };
+42 |     if x { false } else { false };
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: this if-then-else expression returns a bool literal
-  --> $DIR/needless_bool.rs:21:5
+  --> $DIR/needless_bool.rs:43:5
    |
-21 |     if x { true } else { false };
+43 |     if x { true } else { false };
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: you can reduce it to: `x`
 
 error: this if-then-else expression returns a bool literal
-  --> $DIR/needless_bool.rs:22:5
+  --> $DIR/needless_bool.rs:44:5
    |
-22 |     if x { false } else { true };
+44 |     if x { false } else { true };
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: you can reduce it to: `!x`
 
 error: this if-then-else expression returns a bool literal
-  --> $DIR/needless_bool.rs:23:5
+  --> $DIR/needless_bool.rs:45:5
    |
-23 |     if x && y { false } else { true };
+45 |     if x && y { false } else { true };
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: you can reduce it to: `!(x && y)`
 
 error: this if-then-else expression will always return true
-  --> $DIR/needless_bool.rs:35:5
+  --> $DIR/needless_bool.rs:60:5
    |
-35 |     if x { return true } else { return true };
+60 |     if x { return true } else { return true };
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: this if-then-else expression will always return false
-  --> $DIR/needless_bool.rs:40:5
+  --> $DIR/needless_bool.rs:65:5
    |
-40 |     if x { return false } else { return false };
+65 |     if x { return false } else { return false };
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: this if-then-else expression returns a bool literal
-  --> $DIR/needless_bool.rs:45:5
+  --> $DIR/needless_bool.rs:70:5
    |
-45 |     if x { return true } else { return false };
+70 |     if x { return true } else { return false };
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: you can reduce it to: `return x`
 
 error: this if-then-else expression returns a bool literal
-  --> $DIR/needless_bool.rs:50:5
+  --> $DIR/needless_bool.rs:75:5
    |
-50 |     if x && y { return true } else { return false };
+75 |     if x && y { return true } else { return false };
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: you can reduce it to: `return x && y`
 
 error: this if-then-else expression returns a bool literal
-  --> $DIR/needless_bool.rs:55:5
+  --> $DIR/needless_bool.rs:80:5
    |
-55 |     if x { return false } else { return true };
+80 |     if x { return false } else { return true };
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: you can reduce it to: `return !x`
 
 error: this if-then-else expression returns a bool literal
-  --> $DIR/needless_bool.rs:60:5
+  --> $DIR/needless_bool.rs:85:5
    |
-60 |     if x && y { return false } else { return true };
+85 |     if x && y { return false } else { return true };
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: you can reduce it to: `return !(x && y)`
 
-error: aborting due to 11 previous errors
+error: equality checks against true are unnecessary
+  --> $DIR/needless_bool.rs:89:7
+   |
+89 |    if x  == true { };
+   |       ^^^^^^^^^^ help: try simplifying it as shown: `x`
+   |
+   = note: `-D clippy::bool-comparison` implied by `-D warnings`
+
+error: equality checks against false can be replaced by a negation
+  --> $DIR/needless_bool.rs:93:7
+   |
+93 |    if x  == false { };
+   |       ^^^^^^^^^^^ help: try simplifying it as shown: `!x`
+
+error: equality checks against true are unnecessary
+   --> $DIR/needless_bool.rs:104:8
+    |
+104 |     if x == true { };
+    |        ^^^^^^^^^ help: try simplifying it as shown: `x`
+
+error: equality checks against false can be replaced by a negation
+   --> $DIR/needless_bool.rs:105:8
+    |
+105 |     if x == false { };
+    |        ^^^^^^^^^^ help: try simplifying it as shown: `!x`
+
+error: aborting due to 15 previous errors