Auto merge of #10845 - disco07:master, r=giraffate

nonminimal_bool fix double not

fix issue https://github.com/rust-lang/rust-clippy/issues/10836

changelog: Fix [`nonminimal_bool`] false positive when `!!x`, `x` isn't boolean and implements `Not`

2 files changed, 18 insertions, 1 deletions

diff --git a/clippy_lints/src/booleans.rs b/clippy_lints/src/booleans.rs
index 455f0df7cd0..ff0102255a0 100644
--- a/clippy_lints/src/booleans.rs
+++ b/clippy_lints/src/booleans.rs
@@ -88,7 +88,6 @@ impl<'tcx> LateLintPass<'tcx> for NonminimalBool {
         NonminimalBoolVisitor { cx }.visit_body(body);
     }
 }
-
 struct NonminimalBoolVisitor<'a, 'tcx> {
     cx: &'a LateContext<'tcx>,
 }
@@ -473,6 +472,10 @@ impl<'a, 'tcx> Visitor<'tcx> for NonminimalBoolVisitor<'a, 'tcx> {
                     self.bool_expr(e);
                 },
                 ExprKind::Unary(UnOp::Not, inner) => {
+                    if let ExprKind::Unary(UnOp::Not, ex) = inner.kind &&
+                    !self.cx.typeck_results().node_types()[ex.hir_id].is_bool() {
+                        return;
+                    }
                     if self.cx.typeck_results().node_types()[inner.hir_id].is_bool() {
                         self.bool_expr(e);
                     }
diff --git a/tests/ui/nonminimal_bool.rs b/tests/ui/nonminimal_bool.rs
index 80cc7c60f56..fec6b7713ee 100644
--- a/tests/ui/nonminimal_bool.rs
+++ b/tests/ui/nonminimal_bool.rs
@@ -110,3 +110,17 @@ fn issue_10435() {
         println!("{}", line!());
     }
 }
+
+fn issue10836() {
+    struct Foo(bool);
+    impl std::ops::Not for Foo {
+        type Output = bool;
+
+        fn not(self) -> Self::Output {
+            !self.0
+        }
+    }
+
+    // Should not lint
+    let _: bool = !!Foo(true);
+}