[clang-tools-extra] a89141f - [clang-tidy] Add check `readability-avoid-return-with-void-value` (#76249)
via cfe-commits
cfe-commits at lists.llvm.org
Fri Jan 5 15:14:13 PST 2024
Author: Danny Mösch
Date: 2024-01-06T00:14:08+01:00
New Revision: a89141f733cef817c586bb6da0ea69a5a323874e
URL: https://github.com/llvm/llvm-project/commit/a89141f733cef817c586bb6da0ea69a5a323874e
DIFF: https://github.com/llvm/llvm-project/commit/a89141f733cef817c586bb6da0ea69a5a323874e.diff
LOG: [clang-tidy] Add check `readability-avoid-return-with-void-value` (#76249)
Added:
clang-tools-extra/clang-tidy/readability/AvoidReturnWithVoidValueCheck.cpp
clang-tools-extra/clang-tidy/readability/AvoidReturnWithVoidValueCheck.h
clang-tools-extra/docs/clang-tidy/checks/readability/avoid-return-with-void-value.rst
clang-tools-extra/test/clang-tidy/checkers/readability/avoid-return-with-void-value.cpp
Modified:
clang-tools-extra/clang-tidy/readability/CMakeLists.txt
clang-tools-extra/clang-tidy/readability/ReadabilityTidyModule.cpp
clang-tools-extra/docs/ReleaseNotes.rst
clang-tools-extra/docs/clang-tidy/checks/list.rst
Removed:
################################################################################
diff --git a/clang-tools-extra/clang-tidy/readability/AvoidReturnWithVoidValueCheck.cpp b/clang-tools-extra/clang-tidy/readability/AvoidReturnWithVoidValueCheck.cpp
new file mode 100644
index 00000000000000..e3400f614fa564
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/readability/AvoidReturnWithVoidValueCheck.cpp
@@ -0,0 +1,57 @@
+//===--- AvoidReturnWithVoidValueCheck.cpp - clang-tidy -------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "AvoidReturnWithVoidValueCheck.h"
+#include "clang/AST/Stmt.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/ASTMatchers/ASTMatchers.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::readability {
+
+static constexpr auto IgnoreMacrosName = "IgnoreMacros";
+static constexpr auto IgnoreMacrosDefault = true;
+
+static constexpr auto StrictModeName = "StrictMode";
+static constexpr auto StrictModeDefault = true;
+
+AvoidReturnWithVoidValueCheck::AvoidReturnWithVoidValueCheck(
+ StringRef Name, ClangTidyContext *Context)
+ : ClangTidyCheck(Name, Context),
+ IgnoreMacros(
+ Options.getLocalOrGlobal(IgnoreMacrosName, IgnoreMacrosDefault)),
+ StrictMode(Options.getLocalOrGlobal(StrictModeName, StrictModeDefault)) {}
+
+void AvoidReturnWithVoidValueCheck::registerMatchers(MatchFinder *Finder) {
+ Finder->addMatcher(
+ returnStmt(
+ hasReturnValue(allOf(hasType(voidType()), unless(initListExpr()))),
+ optionally(hasParent(compoundStmt().bind("compound_parent"))))
+ .bind("void_return"),
+ this);
+}
+
+void AvoidReturnWithVoidValueCheck::check(
+ const MatchFinder::MatchResult &Result) {
+ const auto *VoidReturn = Result.Nodes.getNodeAs<ReturnStmt>("void_return");
+ if (IgnoreMacros && VoidReturn->getBeginLoc().isMacroID())
+ return;
+ if (!StrictMode && !Result.Nodes.getNodeAs<CompoundStmt>("compound_parent"))
+ return;
+ diag(VoidReturn->getBeginLoc(), "return statement within a void function "
+ "should not have a specified return value");
+}
+
+void AvoidReturnWithVoidValueCheck::storeOptions(
+ ClangTidyOptions::OptionMap &Opts) {
+ Options.store(Opts, IgnoreMacrosName, IgnoreMacros);
+ Options.store(Opts, StrictModeName, StrictMode);
+}
+
+} // namespace clang::tidy::readability
diff --git a/clang-tools-extra/clang-tidy/readability/AvoidReturnWithVoidValueCheck.h b/clang-tools-extra/clang-tidy/readability/AvoidReturnWithVoidValueCheck.h
new file mode 100644
index 00000000000000..f8148db43cd952
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/readability/AvoidReturnWithVoidValueCheck.h
@@ -0,0 +1,44 @@
+//===--- AvoidReturnWithVoidValueCheck.h - clang-tidy -----------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_AVOIDRETURNWITHVOIDVALUECHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_AVOIDRETURNWITHVOIDVALUECHECK_H
+
+#include "../ClangTidyCheck.h"
+
+namespace clang::tidy::readability {
+
+/// Finds return statements with `void` values used within functions with `void`
+/// result types.
+///
+/// For the user-facing documentation see:
+/// http://clang.llvm.org/extra/clang-tidy/checks/readability/avoid-return-with-void-value.html
+class AvoidReturnWithVoidValueCheck : public ClangTidyCheck {
+public:
+ AvoidReturnWithVoidValueCheck(StringRef Name, ClangTidyContext *Context);
+
+ void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+ void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+
+private:
+ std::optional<TraversalKind> getCheckTraversalKind() const override {
+ return TK_IgnoreUnlessSpelledInSource;
+ }
+ bool isLanguageVersionSupported(const LangOptions &LangOpts) const override {
+ return LangOpts.CPlusPlus;
+ }
+ void storeOptions(ClangTidyOptions::OptionMap &Opts) override;
+
+private:
+ bool IgnoreMacros;
+ bool StrictMode;
+};
+
+} // namespace clang::tidy::readability
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_AVOIDRETURNWITHVOIDVALUECHECK_H
diff --git a/clang-tools-extra/clang-tidy/readability/CMakeLists.txt b/clang-tools-extra/clang-tidy/readability/CMakeLists.txt
index 5452c2d48a4617..408c822b861c5f 100644
--- a/clang-tools-extra/clang-tidy/readability/CMakeLists.txt
+++ b/clang-tools-extra/clang-tidy/readability/CMakeLists.txt
@@ -5,6 +5,7 @@ set(LLVM_LINK_COMPONENTS
add_clang_library(clangTidyReadabilityModule
AvoidConstParamsInDecls.cpp
+ AvoidReturnWithVoidValueCheck.cpp
AvoidUnconditionalPreprocessorIfCheck.cpp
BracesAroundStatementsCheck.cpp
ConstReturnTypeCheck.cpp
diff --git a/clang-tools-extra/clang-tidy/readability/ReadabilityTidyModule.cpp b/clang-tools-extra/clang-tidy/readability/ReadabilityTidyModule.cpp
index b8e6e641432060..0b0aad7c0dcb36 100644
--- a/clang-tools-extra/clang-tidy/readability/ReadabilityTidyModule.cpp
+++ b/clang-tools-extra/clang-tidy/readability/ReadabilityTidyModule.cpp
@@ -10,6 +10,7 @@
#include "../ClangTidyModule.h"
#include "../ClangTidyModuleRegistry.h"
#include "AvoidConstParamsInDecls.h"
+#include "AvoidReturnWithVoidValueCheck.h"
#include "AvoidUnconditionalPreprocessorIfCheck.h"
#include "BracesAroundStatementsCheck.h"
#include "ConstReturnTypeCheck.h"
@@ -63,6 +64,8 @@ class ReadabilityModule : public ClangTidyModule {
void addCheckFactories(ClangTidyCheckFactories &CheckFactories) override {
CheckFactories.registerCheck<AvoidConstParamsInDecls>(
"readability-avoid-const-params-in-decls");
+ CheckFactories.registerCheck<AvoidReturnWithVoidValueCheck>(
+ "readability-avoid-return-with-void-value");
CheckFactories.registerCheck<AvoidUnconditionalPreprocessorIfCheck>(
"readability-avoid-unconditional-preprocessor-if");
CheckFactories.registerCheck<BracesAroundStatementsCheck>(
diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst
index 4d25e2ebe85f5f..08ade306b5a077 100644
--- a/clang-tools-extra/docs/ReleaseNotes.rst
+++ b/clang-tools-extra/docs/ReleaseNotes.rst
@@ -230,6 +230,12 @@ New checks
Detects C++ code where a reference variable is used to extend the lifetime
of a temporary object that has just been constructed.
+- New :doc:`readability-avoid-return-with-void-value
+ <clang-tidy/checks/readability/avoid-return-with-void-value>` check.
+
+ Finds return statements with ``void`` values used within functions with
+ ``void`` result types.
+
New check aliases
^^^^^^^^^^^^^^^^^
diff --git a/clang-tools-extra/docs/clang-tidy/checks/list.rst b/clang-tools-extra/docs/clang-tidy/checks/list.rst
index b36bf7d497b9dd..2f86121ad87299 100644
--- a/clang-tools-extra/docs/clang-tidy/checks/list.rst
+++ b/clang-tools-extra/docs/clang-tidy/checks/list.rst
@@ -337,6 +337,7 @@ Clang-Tidy Checks
:doc:`portability-simd-intrinsics <portability/simd-intrinsics>`,
:doc:`portability-std-allocator-const <portability/std-allocator-const>`,
:doc:`readability-avoid-const-params-in-decls <readability/avoid-const-params-in-decls>`, "Yes"
+ :doc:`readability-avoid-return-with-void-value <readability/avoid-return-with-void-value>`,
:doc:`readability-avoid-unconditional-preprocessor-if <readability/avoid-unconditional-preprocessor-if>`,
:doc:`readability-braces-around-statements <readability/braces-around-statements>`, "Yes"
:doc:`readability-const-return-type <readability/const-return-type>`, "Yes"
diff --git a/clang-tools-extra/docs/clang-tidy/checks/readability/avoid-return-with-void-value.rst b/clang-tools-extra/docs/clang-tidy/checks/readability/avoid-return-with-void-value.rst
new file mode 100644
index 00000000000000..d802f9be829c46
--- /dev/null
+++ b/clang-tools-extra/docs/clang-tidy/checks/readability/avoid-return-with-void-value.rst
@@ -0,0 +1,51 @@
+.. title:: clang-tidy - readability-avoid-return-with-void-value
+
+readability-avoid-return-with-void-value
+========================================
+
+Finds return statements with ``void`` values used within functions with
+``void`` result types.
+
+A function with a ``void`` return type is intended to perform a task without
+producing a return value. Return statements with expressions could lead
+to confusion and may miscommunicate the function's intended behavior.
+
+Example:
+
+.. code-block::
+
+ void g();
+ void f() {
+ // ...
+ return g();
+ }
+
+In a long function body, the ``return`` statement suggests that the function
+returns a value. However, ``return g();`` is a combination of two statements
+that should be written as
+
+.. code-block::
+
+ g();
+ return;
+
+to make clear that ``g()`` is called and immediately afterwards the function
+returns (nothing).
+
+In C, the same issue is detected by the compiler if the ``-Wpedantic`` mode
+is enabled.
+
+Options
+-------
+
+.. option:: IgnoreMacros
+
+ The value `false` specifies that return statements expanded
+ from macros are not checked. The default value is `true`.
+
+.. option:: StrictMode
+
+ The value `false` specifies that a direct return statement shall
+ be excluded from the analysis if it is the only statement not
+ contained in a block like ``if (cond) return g();``. The default
+ value is `true`.
diff --git a/clang-tools-extra/test/clang-tidy/checkers/readability/avoid-return-with-void-value.cpp b/clang-tools-extra/test/clang-tidy/checkers/readability/avoid-return-with-void-value.cpp
new file mode 100644
index 00000000000000..f00407c99ce570
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/checkers/readability/avoid-return-with-void-value.cpp
@@ -0,0 +1,69 @@
+// 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 {}; }
+
+using VOID = void;
+
+VOID f12();
+
+VOID f13() {
+ return f12();
+ // 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]
+}
More information about the cfe-commits
mailing list