Auto merge of rust-lang#12845 - cookie-s:dedup-boolmethods-diags, r=Jarcho

Dedup nonminimal_bool_methods diags

Relates to rust-lang#12379

Fix `nonminimal_bool` lint so that it doesn't check the same span multiple times.

`NotSimplificationVisitor` was called for each expression from `NonminimalBoolVisitor` whereas `NotSimplificationVisitor` also recursively checked all expressions.

---

changelog: [`nonminimal_bool`]: Fix duplicate diagnostics

Author: bors

clippy_lints/src/booleans.rs

@@ -174,6 +174,25 @@ fn check_inverted_bool_in_condition(
     );
 }
 
+fn check_simplify_not(cx: &LateContext<'_>, expr: &Expr<'_>) {
+    if let ExprKind::Unary(UnOp::Not, inner) = &expr.kind
+        && !expr.span.from_expansion()
+        && !inner.span.from_expansion()
+        && let Some(suggestion) = simplify_not(cx, inner)
+        && cx.tcx.lint_level_at_node(NONMINIMAL_BOOL, expr.hir_id).0 != Level::Allow
+    {
+        span_lint_and_sugg(
+            cx,
+            NONMINIMAL_BOOL,
+            expr.span,
+            "this boolean expression can be simplified",
+            "try",
+            suggestion,
+            Applicability::MachineApplicable,
+        );
+    }
+}
+
 struct NonminimalBoolVisitor<'a, 'tcx> {
     cx: &'a LateContext<'tcx>,
 }
@@ -542,8 +561,7 @@ impl<'a, 'tcx> NonminimalBoolVisitor<'a, 'tcx> {
                 }
             };
             if improvements.is_empty() {
-                let mut visitor = NotSimplificationVisitor { cx: self.cx };
-                visitor.visit_expr(e);
+                check_simplify_not(self.cx, e);
             } else {
                 nonminimal_bool_lint(
                     improvements
@@ -586,30 +604,3 @@ fn implements_ord(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
         .get_diagnostic_item(sym::Ord)
         .map_or(false, |id| implements_trait(cx, ty, id, &[]))
 }
-
-struct NotSimplificationVisitor<'a, 'tcx> {
-    cx: &'a LateContext<'tcx>,
-}
-
-impl<'a, 'tcx> Visitor<'tcx> for NotSimplificationVisitor<'a, 'tcx> {
-    fn visit_expr(&mut self, expr: &'tcx Expr<'_>) {
-        if let ExprKind::Unary(UnOp::Not, inner) = &expr.kind
-            && !expr.span.from_expansion()
-            && !inner.span.from_expansion()
-            && let Some(suggestion) = simplify_not(self.cx, inner)
-            && self.cx.tcx.lint_level_at_node(NONMINIMAL_BOOL, expr.hir_id).0 != Level::Allow
-        {
-            span_lint_and_sugg(
-                self.cx,
-                NONMINIMAL_BOOL,
-                expr.span,
-                "this boolean expression can be simplified",
-                "try",
-                suggestion,
-                Applicability::MachineApplicable,
-            );
-        }
-
-        walk_expr(self, expr);
-    }
-}

tests/ui/nonminimal_bool_methods.fixed

@@ -1,5 +1,3 @@
-//@compile-flags: -Zdeduplicate-diagnostics=yes
-
 #![allow(unused, clippy::diverging_sub_expression, clippy::needless_if)]
 #![warn(clippy::nonminimal_bool)]
 

tests/ui/nonminimal_bool_methods.rs

@@ -1,5 +1,3 @@
-//@compile-flags: -Zdeduplicate-diagnostics=yes
-
 #![allow(unused, clippy::diverging_sub_expression, clippy::needless_if)]
 #![warn(clippy::nonminimal_bool)]
 

tests/ui/nonminimal_bool_methods.stderr

@@ -1,5 +1,5 @@
 error: this boolean expression can be simplified
-  --> tests/ui/nonminimal_bool_methods.rs:10:13
+  --> tests/ui/nonminimal_bool_methods.rs:8:13
    |
 LL |     let _ = !a.is_some();
    |             ^^^^^^^^^^^^ help: try: `a.is_none()`
@@ -8,91 +8,91 @@ LL |     let _ = !a.is_some();
    = help: to override `-D warnings` add `#[allow(clippy::nonminimal_bool)]`
 
 error: this boolean expression can be simplified
-  --> tests/ui/nonminimal_bool_methods.rs:12:13
+  --> tests/ui/nonminimal_bool_methods.rs:10:13
    |
 LL |     let _ = !a.is_none();
    |             ^^^^^^^^^^^^ help: try: `a.is_some()`
 
 error: this boolean expression can be simplified
-  --> tests/ui/nonminimal_bool_methods.rs:14:13
+  --> tests/ui/nonminimal_bool_methods.rs:12:13
    |
 LL |     let _ = !b.is_err();
    |             ^^^^^^^^^^^ help: try: `b.is_ok()`
 
 error: this boolean expression can be simplified
-  --> tests/ui/nonminimal_bool_methods.rs:16:13
+  --> tests/ui/nonminimal_bool_methods.rs:14:13
    |
 LL |     let _ = !b.is_ok();
    |             ^^^^^^^^^^ help: try: `b.is_err()`
 
 error: this boolean expression can be simplified
-  --> tests/ui/nonminimal_bool_methods.rs:18:13
+  --> tests/ui/nonminimal_bool_methods.rs:16:13
    |
 LL |     let _ = !(a.is_some() && !c);
    |             ^^^^^^^^^^^^^^^^^^^^ help: try: `a.is_none() || c`
 
 error: this boolean expression can be simplified
-  --> tests/ui/nonminimal_bool_methods.rs:19:13
+  --> tests/ui/nonminimal_bool_methods.rs:17:13
    |
 LL |     let _ = !(a.is_some() || !c);
    |             ^^^^^^^^^^^^^^^^^^^^ help: try: `a.is_none() && c`
 
 error: this boolean expression can be simplified
-  --> tests/ui/nonminimal_bool_methods.rs:20:26
+  --> tests/ui/nonminimal_bool_methods.rs:18:26
    |
 LL |     let _ = !(!c ^ c) || !a.is_some();
    |                          ^^^^^^^^^^^^ help: try: `a.is_none()`
 
 error: this boolean expression can be simplified
-  --> tests/ui/nonminimal_bool_methods.rs:21:25
+  --> tests/ui/nonminimal_bool_methods.rs:19:25
    |
 LL |     let _ = (!c ^ c) || !a.is_some();
    |                         ^^^^^^^^^^^^ help: try: `a.is_none()`
 
 error: this boolean expression can be simplified
-  --> tests/ui/nonminimal_bool_methods.rs:22:23
+  --> tests/ui/nonminimal_bool_methods.rs:20:23
    |
 LL |     let _ = !c ^ c || !a.is_some();
    |                       ^^^^^^^^^^^^ help: try: `a.is_none()`
 
 error: this boolean expression can be simplified
-  --> tests/ui/nonminimal_bool_methods.rs:94:8
+  --> tests/ui/nonminimal_bool_methods.rs:92:8
    |
 LL |     if !res.is_ok() {}
    |        ^^^^^^^^^^^^ help: try: `res.is_err()`
 
 error: this boolean expression can be simplified
-  --> tests/ui/nonminimal_bool_methods.rs:95:8
+  --> tests/ui/nonminimal_bool_methods.rs:93:8
    |
 LL |     if !res.is_err() {}
    |        ^^^^^^^^^^^^^ help: try: `res.is_ok()`
 
 error: this boolean expression can be simplified
-  --> tests/ui/nonminimal_bool_methods.rs:98:8
+  --> tests/ui/nonminimal_bool_methods.rs:96:8
    |
 LL |     if !res.is_some() {}
    |        ^^^^^^^^^^^^^^ help: try: `res.is_none()`
 
 error: this boolean expression can be simplified
-  --> tests/ui/nonminimal_bool_methods.rs:99:8
+  --> tests/ui/nonminimal_bool_methods.rs:97:8
    |
 LL |     if !res.is_none() {}
    |        ^^^^^^^^^^^^^^ help: try: `res.is_some()`
 
 error: this boolean expression can be simplified
-  --> tests/ui/nonminimal_bool_methods.rs:115:8
+  --> tests/ui/nonminimal_bool_methods.rs:113:8
    |
 LL |     if !(a as u64 >= b) {}
    |        ^^^^^^^^^^^^^^^^ help: try: `(a as u64) < b`
 
 error: this boolean expression can be simplified
-  --> tests/ui/nonminimal_bool_methods.rs:116:8
+  --> tests/ui/nonminimal_bool_methods.rs:114:8
    |
 LL |     if !((a as u64) >= b) {}
    |        ^^^^^^^^^^^^^^^^^^ help: try: `(a as u64) < b`
 
 error: this boolean expression can be simplified
-  --> tests/ui/nonminimal_bool_methods.rs:117:8
+  --> tests/ui/nonminimal_bool_methods.rs:115:8
    |
 LL |     if !(a as u64 <= b) {}
    |        ^^^^^^^^^^^^^^^^ help: try: `a as u64 > b`