[clang-tidy] Improved readability-bool-conversion to be more consistent when using parentheses (#72068)

Provides more consistent suggestions when parentheses are added to the return value.

Fixes #71852

Author: felix642

clang-tools-extra/clang-tidy/readability/ImplicitBoolConversionCheck.cpp

@@ -152,7 +152,8 @@ StringRef getEquivalentBoolLiteralForExpr(const Expr *Expression,
     return "false";
   }
 
-  if (const auto *IntLit = dyn_cast<IntegerLiteral>(Expression)) {
+  if (const auto *IntLit =
+          dyn_cast<IntegerLiteral>(Expression->IgnoreParens())) {
     return (IntLit->getValue() == 0) ? "false" : "true";
   }
 
@@ -385,7 +386,7 @@ void ImplicitBoolConversionCheck::handleCastFromBool(
               << DestType;
 
   if (const auto *BoolLiteral =
-          dyn_cast<CXXBoolLiteralExpr>(Cast->getSubExpr())) {
+          dyn_cast<CXXBoolLiteralExpr>(Cast->getSubExpr()->IgnoreParens())) {
     Diag << tooling::fixit::createReplacement(
         *Cast, getEquivalentForBoolLiteral(BoolLiteral, DestType, Context));
   } else {

clang-tools-extra/docs/ReleaseNotes.rst

@@ -416,7 +416,8 @@ Changes in existing checks
 - Improved :doc:`readability-implicit-bool-conversion
   <clang-tidy/checks/readability/implicit-bool-conversion>` check to take
   do-while loops into account for the `AllowIntegerConditions` and
-  `AllowPointerConditions` options.
+  `AllowPointerConditions` options. It also now provides more consistent
+  suggestions when parentheses are added to the return value.
 
 - Improved :doc:`readability-non-const-parameter
   <clang-tidy/checks/readability/non-const-parameter>` check to ignore

clang-tools-extra/test/clang-tidy/checkers/readability/implicit-bool-conversion.cpp

@@ -472,6 +472,36 @@ bool f(S& s) {
 
 } // namespace ignore_1bit_bitfields
 
+int implicitConversionReturnInt()
+{
+    return true;
+    // CHECK-MESSAGES: :[[@LINE-1]]:12: warning: implicit conversion bool -> 'int'
+    // CHECK-FIXES: return 1
+}
+
+int implicitConversionReturnIntWithParens()
+{
+    return (true);
+    // CHECK-MESSAGES: :[[@LINE-1]]:12: warning: implicit conversion bool -> 'int'
+    // CHECK-FIXES: return 1
+}
+
+
+bool implicitConversionReturnBool()
+{
+    return 1;
+    // CHECK-MESSAGES: :[[@LINE-1]]:12: warning: implicit conversion 'int' -> bool
+    // CHECK-FIXES: return true
+}
+
+bool implicitConversionReturnBoolWithParens()
+{
+    return (1);
+    // CHECK-MESSAGES: :[[@LINE-1]]:12: warning: implicit conversion 'int' -> bool
+    // CHECK-FIXES: return true
+}
+
+
 namespace PR47000 {
   int to_int(bool x) { return int{x}; }