[clang-tools-extra] [clang-tidy] Add check `readability-avoid-return-with-void-value` (PR #76249)

[Piotr Zegar via cfe-commits]

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In-Reply-To: <llvm.org/llvm/llvm-project/pull/76249 at github.com>


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@@ -0,0 +1,59 @@
+// RUN: %check_clang_tidy %s readability-avoid-return-with-void-value %t
+// RUN: %check_clang_tidy -check-suffixes=,INCLUDE-MACROS %s readability-avoid-return-with-void-value %t \
+// RUN:     -- -config="{CheckOptions: [{key: readability-avoid-return-with-void-value.IgnoreMacros, value: false}]}" \
+// RUN:     --
+// RUN: %check_clang_tidy -check-suffixes=LENIENT %s readability-avoid-return-with-void-value %t \
+// RUN:     -- -config="{CheckOptions: [{key: readability-avoid-return-with-void-value.StrictMode, value: false}]}" \
+// RUN:     --
+
+void f1();
+
+void f2() {
+    return f1();
+    // CHECK-MESSAGES: :[[@LINE-1]]:5: warning: return statement within a void function should not have a specified return value [readability-avoid-return-with-void-value]
+    // CHECK-MESSAGES-LENIENT: :[[@LINE-2]]:5: warning: return statement within a void function should not have a specified return value [readability-avoid-return-with-void-value]
+}
+
+void f3(bool b) {
+    if (b) return f1();
+    // CHECK-MESSAGES: :[[@LINE-1]]:12: warning: return statement within a void function should not have a specified return value [readability-avoid-return-with-void-value]
+    return f2();
+    // CHECK-MESSAGES: :[[@LINE-1]]:5: warning: return statement within a void function should not have a specified return value [readability-avoid-return-with-void-value]
+    // CHECK-MESSAGES-LENIENT: :[[@LINE-2]]:5: warning: return statement within a void function should not have a specified return value [readability-avoid-return-with-void-value]
+}
+
+template<class T>
+T f4() {}
+
+void f5() {
+    return f4<void>();
+    // CHECK-MESSAGES: :[[@LINE-1]]:5: warning: return statement within a void function should not have a specified return value [readability-avoid-return-with-void-value]
+    // CHECK-MESSAGES-LENIENT: :[[@LINE-2]]:5: warning: return statement within a void function should not have a specified return value [readability-avoid-return-with-void-value]
+}
+
+void f6() { return; }
+
+int f7() { return 1; }
+
+int f8() { return f7(); }
+
+void f9() {
+    return (void)f7();
+    // CHECK-MESSAGES: :[[@LINE-1]]:5: warning: return statement within a void function should not have a specified return value [readability-avoid-return-with-void-value]
+    // CHECK-MESSAGES-LENIENT: :[[@LINE-2]]:5: warning: return statement within a void function should not have a specified return value [readability-avoid-return-with-void-value]
+}
+
+#define RETURN_VOID return (void)1
+
+void f10() {
+    RETURN_VOID;
+    // CHECK-MESSAGES-INCLUDE-MACROS: :[[@LINE-1]]:5: warning: return statement within a void function should not have a specified return value [readability-avoid-return-with-void-value]
+}
+
+template <typename A> 
+struct C {
+  C(A) {}
+};
+
+template <class T> 
+C<T> f11() { return {}; }
----------------
PiotrZSL wrote:

Add test like this:
```
using VOID = void;

VOID doOther();

VOID doSomething()
{
    return doOther();
}```

You may need to use `hasCanonicalType`...

https://github.com/llvm/llvm-project/pull/76249