https://github.com/unterumarmung created https://github.com/llvm/llvm-project/pull/180408
Handle braced-init list arguments in bugprone-argument-comment and\nadd coverage for initializer_list and designated initializers. Fixes: https://github.com/llvm/llvm-project/issues/171842 >From 0583fed4e6e4082aa7be5101b0171c7fdae144ab Mon Sep 17 00:00:00 2001 From: Daniil Dudkin <[email protected]> Date: Sun, 8 Feb 2026 16:23:22 +0300 Subject: [PATCH] clang-tidy: comment braced-init list arguments Handle braced-init list arguments in bugprone-argument-comment and\nadd coverage for initializer_list and designated initializers. --- .../bugprone/ArgumentCommentCheck.cpp | 30 ++++++- clang-tools-extra/docs/ReleaseNotes.rst | 5 +- .../checks/bugprone/argument-comment.rst | 2 + .../bugprone/argument-comment-literals.cpp | 80 ++++++++++++++++++- 4 files changed, 111 insertions(+), 6 deletions(-) diff --git a/clang-tools-extra/clang-tidy/bugprone/ArgumentCommentCheck.cpp b/clang-tools-extra/clang-tidy/bugprone/ArgumentCommentCheck.cpp index d46896808bd09..86c1252b5e913 100644 --- a/clang-tools-extra/clang-tidy/bugprone/ArgumentCommentCheck.cpp +++ b/clang-tools-extra/clang-tidy/bugprone/ArgumentCommentCheck.cpp @@ -8,6 +8,7 @@ #include "ArgumentCommentCheck.h" #include "clang/AST/ASTContext.h" +#include "clang/AST/ExprCXX.h" #include "clang/ASTMatchers/ASTMatchFinder.h" #include "clang/Lex/Lexer.h" #include "clang/Lex/Token.h" @@ -242,14 +243,37 @@ static const FunctionDecl *resolveMocks(const FunctionDecl *Func) { return Func; } +static bool isBracedInitListExpr(const Expr *Arg) { + Arg = Arg->IgnoreImplicit(); + // List-initialization can be represented by a list expression itself or by a + // list-initialized constructor/cast. Treat all of these as braced-init uses. + if (isa<InitListExpr>(Arg)) + return true; + if (const auto *StdInit = dyn_cast<CXXStdInitializerListExpr>(Arg)) + return isBracedInitListExpr(StdInit->getSubExpr()->IgnoreImplicit()); + if (const auto *Ctor = dyn_cast<CXXConstructExpr>(Arg)) + return Ctor->isListInitialization(); + if (const auto *FuncCast = dyn_cast<CXXFunctionalCastExpr>(Arg)) + return FuncCast->isListInitialization(); + return false; +} + // Given the argument type and the options determine if we should // be adding an argument comment. bool ArgumentCommentCheck::shouldAddComment(const Expr *Arg) const { - Arg = Arg->IgnoreImpCasts(); - if (isa<UnaryOperator>(Arg)) - Arg = cast<UnaryOperator>(Arg)->getSubExpr(); + // Strip implicit wrappers so brace-init arguments bound to references still + // look like list-initialization at this point. + Arg = Arg->IgnoreImplicit(); + if (const auto *UO = dyn_cast<UnaryOperator>(Arg)) + Arg = UO->getSubExpr()->IgnoreImplicit(); if (Arg->getExprLoc().isMacroID()) return false; + + // Braced-init list arguments (e.g. {} or Type{}) are commonly unclear even + // when the type name is explicit, so always suggest a parameter comment. + if (isBracedInitListExpr(Arg)) + return true; + return (CommentBoolLiterals && isa<CXXBoolLiteralExpr>(Arg)) || (CommentIntegerLiterals && isa<IntegerLiteral>(Arg)) || (CommentFloatLiterals && isa<FloatingLiteral>(Arg)) || diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst index 7b5b332bdb8a2..cf5667cde6205 100644 --- a/clang-tools-extra/docs/ReleaseNotes.rst +++ b/clang-tools-extra/docs/ReleaseNotes.rst @@ -141,8 +141,9 @@ Changes in existing checks ^^^^^^^^^^^^^^^^^^^^^^^^^^ - Improved :doc:`bugprone-argument-comment - <clang-tidy/checks/bugprone/argument-comment>` to also check for C++11 - inherited constructors. + <clang-tidy/checks/bugprone/argument-comment>`: + - Also checks for C++11 inherited constructors. + - Comments braced-init list arguments such as ``{}`` and ``Type{}``. - Improved :doc:`bugprone-macro-parentheses <clang-tidy/checks/bugprone/macro-parentheses>` check by printing the macro diff --git a/clang-tools-extra/docs/clang-tidy/checks/bugprone/argument-comment.rst b/clang-tools-extra/docs/clang-tidy/checks/bugprone/argument-comment.rst index 8770d7224137a..2c495df82752e 100644 --- a/clang-tools-extra/docs/clang-tidy/checks/bugprone/argument-comment.rst +++ b/clang-tools-extra/docs/clang-tidy/checks/bugprone/argument-comment.rst @@ -18,6 +18,8 @@ that are placed right before the argument. // warning: argument name 'bar' in comment does not match parameter name 'foo' The check tries to detect typos and suggest automated fixes for them. +It also suggests comments for braced-init list arguments (e.g., ``{}`` or +``Type{}``), since the intent is often unclear at the call site. Options ------- diff --git a/clang-tools-extra/test/clang-tidy/checkers/bugprone/argument-comment-literals.cpp b/clang-tools-extra/test/clang-tidy/checkers/bugprone/argument-comment-literals.cpp index f03488a14d9f5..9fac137a8d74c 100644 --- a/clang-tools-extra/test/clang-tidy/checkers/bugprone/argument-comment-literals.cpp +++ b/clang-tools-extra/test/clang-tidy/checkers/bugprone/argument-comment-literals.cpp @@ -1,4 +1,13 @@ -// RUN: %check_clang_tidy %s bugprone-argument-comment %t -- \ +// RUN: %check_clang_tidy -std=c++11 %s bugprone-argument-comment %t -- \ +// RUN: -config="{CheckOptions: { \ +// RUN: bugprone-argument-comment.CommentBoolLiterals: true, \ +// RUN: bugprone-argument-comment.CommentIntegerLiterals: true, \ +// RUN: bugprone-argument-comment.CommentFloatLiterals: true, \ +// RUN: bugprone-argument-comment.CommentUserDefinedLiterals: true, \ +// RUN: bugprone-argument-comment.CommentStringLiterals: true, \ +// RUN: bugprone-argument-comment.CommentNullPtrs: true, \ +// RUN: bugprone-argument-comment.CommentCharacterLiterals: true}}" -- +// RUN: %check_clang_tidy -check-suffixes=,CXX20 -std=c++20 %s bugprone-argument-comment %t -- \ // RUN: -config="{CheckOptions: { \ // RUN: bugprone-argument-comment.CommentBoolLiterals: true, \ // RUN: bugprone-argument-comment.CommentIntegerLiterals: true, \ @@ -185,3 +194,72 @@ void ignores_underscores() { // CHECK-MESSAGES: [[@LINE-1]]:5: warning: argument comment missing for literal argument // CHECK-FIXES: f(/*_with_underscores_=*/true); } + +namespace std { +using size_t = decltype(sizeof(0)); + +template <typename T> +class vector { +public: + vector(); +}; + +template <typename T> +class initializer_list { + const T *Begin; + const T *End; + +public: + initializer_list() : Begin(nullptr), End(nullptr) {} + const T *begin() const { return Begin; } + const T *end() const { return End; } + size_t size() const { return static_cast<size_t>(End - Begin); } +}; +} // namespace std + +namespace GH171842 { + +struct T { + int value; +}; + +struct Agg { + int x; + int y; +}; + +void foo(T some_arg, const std::vector<int> &dims); +void foo_init_list(T some_arg, std::initializer_list<int> dims); +void foo_designated(T some_arg, const Agg &dims); + +void test_braced_init_list() { + T some_arg{0}; + + foo(some_arg, {}); + // CHECK-MESSAGES: [[@LINE-1]]:17: warning: argument comment missing for literal argument 'dims' [bugprone-argument-comment] + // CHECK-FIXES: foo(some_arg, /*dims=*/{}); + + foo(some_arg, std::vector<int>{}); + // CHECK-MESSAGES: [[@LINE-1]]:17: warning: argument comment missing for literal argument 'dims' [bugprone-argument-comment] + // CHECK-FIXES: foo(some_arg, /*dims=*/std::vector<int>{}); +} + +void test_initializer_list() { + T some_arg{0}; + + foo_init_list(some_arg, {1, 2, 3}); + // CHECK-MESSAGES: [[@LINE-1]]:27: warning: argument comment missing for literal argument 'dims' [bugprone-argument-comment] + // CHECK-FIXES: foo_init_list(some_arg, /*dims=*/{1, 2, 3}); +} + +// C++20-only syntax is exercised in the separate C++20 run above. +#if __cplusplus >= 202002L +void test_designated_init() { + T some_arg{0}; + + foo_designated(some_arg, Agg{.x = 1}); + // CHECK-MESSAGES-CXX20: [[@LINE-1]]:28: warning: argument comment missing for literal argument 'dims' [bugprone-argument-comment] + // CHECK-FIXES-CXX20: foo_designated(some_arg, /*dims=*/Agg{.x = 1}); +} +#endif +} // namespace GH171842 _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
