Author: Congcong Cai Date: 2024-04-01T15:53:57+08:00 New Revision: 3365d62179011aad6da3e4cbcb31044eec3462a2
URL: https://github.com/llvm/llvm-project/commit/3365d62179011aad6da3e4cbcb31044eec3462a2 DIFF: https://github.com/llvm/llvm-project/commit/3365d62179011aad6da3e4cbcb31044eec3462a2.diff LOG: [clang-tidy] add new check readability-enum-initial-value (#86129) Fixes: #85243. Added: clang-tools-extra/clang-tidy/readability/EnumInitialValueCheck.cpp clang-tools-extra/clang-tidy/readability/EnumInitialValueCheck.h clang-tools-extra/docs/clang-tidy/checks/readability/enum-initial-value.rst clang-tools-extra/test/clang-tidy/checkers/readability/enum-initial-value.c clang-tools-extra/test/clang-tidy/checkers/readability/enum-initial-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/CMakeLists.txt b/clang-tools-extra/clang-tidy/readability/CMakeLists.txt index 5728c9970fb65d..dd772d69202548 100644 --- a/clang-tools-extra/clang-tidy/readability/CMakeLists.txt +++ b/clang-tools-extra/clang-tidy/readability/CMakeLists.txt @@ -17,6 +17,7 @@ add_clang_library(clangTidyReadabilityModule DeleteNullPointerCheck.cpp DuplicateIncludeCheck.cpp ElseAfterReturnCheck.cpp + EnumInitialValueCheck.cpp FunctionCognitiveComplexityCheck.cpp FunctionSizeCheck.cpp IdentifierLengthCheck.cpp diff --git a/clang-tools-extra/clang-tidy/readability/EnumInitialValueCheck.cpp b/clang-tools-extra/clang-tidy/readability/EnumInitialValueCheck.cpp new file mode 100644 index 00000000000000..8f2841c32259a2 --- /dev/null +++ b/clang-tools-extra/clang-tidy/readability/EnumInitialValueCheck.cpp @@ -0,0 +1,200 @@ +//===--- EnumInitialValueCheck.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 "EnumInitialValueCheck.h" +#include "../utils/LexerUtils.h" +#include "clang/AST/Decl.h" +#include "clang/ASTMatchers/ASTMatchFinder.h" +#include "clang/ASTMatchers/ASTMatchers.h" +#include "clang/Basic/Diagnostic.h" +#include "clang/Basic/SourceLocation.h" +#include "llvm/ADT/STLExtras.h" +#include "llvm/ADT/SmallString.h" + +using namespace clang::ast_matchers; + +namespace clang::tidy::readability { + +static bool isNoneEnumeratorsInitialized(const EnumDecl &Node) { + return llvm::all_of(Node.enumerators(), [](const EnumConstantDecl *ECD) { + return ECD->getInitExpr() == nullptr; + }); +} + +static bool isOnlyFirstEnumeratorInitialized(const EnumDecl &Node) { + bool IsFirst = true; + for (const EnumConstantDecl *ECD : Node.enumerators()) { + if ((IsFirst && ECD->getInitExpr() == nullptr) || + (!IsFirst && ECD->getInitExpr() != nullptr)) + return false; + IsFirst = false; + } + return !IsFirst; +} + +static bool areAllEnumeratorsInitialized(const EnumDecl &Node) { + return llvm::all_of(Node.enumerators(), [](const EnumConstantDecl *ECD) { + return ECD->getInitExpr() != nullptr; + }); +} + +/// Check if \p Enumerator is initialized with a (potentially negated) \c +/// IntegerLiteral. +static bool isInitializedByLiteral(const EnumConstantDecl *Enumerator) { + const Expr *const Init = Enumerator->getInitExpr(); + if (!Init) + return false; + return Init->isIntegerConstantExpr(Enumerator->getASTContext()); +} + +static void cleanInitialValue(DiagnosticBuilder &Diag, + const EnumConstantDecl *ECD, + const SourceManager &SM, + const LangOptions &LangOpts) { + const SourceRange InitExprRange = ECD->getInitExpr()->getSourceRange(); + if (InitExprRange.isInvalid() || InitExprRange.getBegin().isMacroID() || + InitExprRange.getEnd().isMacroID()) + return; + std::optional<Token> EqualToken = utils::lexer::findNextTokenSkippingComments( + ECD->getLocation(), SM, LangOpts); + if (!EqualToken.has_value() || + EqualToken.value().getKind() != tok::TokenKind::equal) + return; + const SourceLocation EqualLoc{EqualToken->getLocation()}; + if (EqualLoc.isInvalid() || EqualLoc.isMacroID()) + return; + Diag << FixItHint::CreateRemoval(EqualLoc) + << FixItHint::CreateRemoval(InitExprRange); + return; +} + +namespace { + +AST_MATCHER(EnumDecl, isMacro) { + SourceLocation Loc = Node.getBeginLoc(); + return Loc.isMacroID(); +} + +AST_MATCHER(EnumDecl, hasConsistentInitialValues) { + return isNoneEnumeratorsInitialized(Node) || + isOnlyFirstEnumeratorInitialized(Node) || + areAllEnumeratorsInitialized(Node); +} + +AST_MATCHER(EnumDecl, hasZeroInitialValueForFirstEnumerator) { + const EnumDecl::enumerator_range Enumerators = Node.enumerators(); + if (Enumerators.empty()) + return false; + const EnumConstantDecl *ECD = *Enumerators.begin(); + return isOnlyFirstEnumeratorInitialized(Node) && + isInitializedByLiteral(ECD) && ECD->getInitVal().isZero(); +} + +/// Excludes bitfields because enumerators initialized with the result of a +/// bitwise operator on enumeration values or any other expr that is not a +/// potentially negative integer literal. +/// Enumerations where it is not directly clear if they are used with +/// bitmask, evident when enumerators are only initialized with (potentially +/// negative) integer literals, are ignored. This is also the case when all +/// enumerators are powers of two (e.g., 0, 1, 2). +AST_MATCHER(EnumDecl, hasSequentialInitialValues) { + const EnumDecl::enumerator_range Enumerators = Node.enumerators(); + if (Enumerators.empty()) + return false; + const EnumConstantDecl *const FirstEnumerator = *Node.enumerator_begin(); + llvm::APSInt PrevValue = FirstEnumerator->getInitVal(); + if (!isInitializedByLiteral(FirstEnumerator)) + return false; + bool AllEnumeratorsArePowersOfTwo = true; + for (const EnumConstantDecl *Enumerator : llvm::drop_begin(Enumerators)) { + const llvm::APSInt NewValue = Enumerator->getInitVal(); + if (NewValue != ++PrevValue) + return false; + if (!isInitializedByLiteral(Enumerator)) + return false; + PrevValue = NewValue; + AllEnumeratorsArePowersOfTwo &= NewValue.isPowerOf2(); + } + return !AllEnumeratorsArePowersOfTwo; +} + +} // namespace + +EnumInitialValueCheck::EnumInitialValueCheck(StringRef Name, + ClangTidyContext *Context) + : ClangTidyCheck(Name, Context), + AllowExplicitZeroFirstInitialValue( + Options.get("AllowExplicitZeroFirstInitialValue", true)), + AllowExplicitSequentialInitialValues( + Options.get("AllowExplicitSequentialInitialValues", true)) {} + +void EnumInitialValueCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) { + Options.store(Opts, "AllowExplicitZeroFirstInitialValue", + AllowExplicitZeroFirstInitialValue); + Options.store(Opts, "AllowExplicitSequentialInitialValues", + AllowExplicitSequentialInitialValues); +} + +void EnumInitialValueCheck::registerMatchers(MatchFinder *Finder) { + Finder->addMatcher( + enumDecl(unless(isMacro()), unless(hasConsistentInitialValues())) + .bind("inconsistent"), + this); + if (!AllowExplicitZeroFirstInitialValue) + Finder->addMatcher( + enumDecl(hasZeroInitialValueForFirstEnumerator()).bind("zero_first"), + this); + if (!AllowExplicitSequentialInitialValues) + Finder->addMatcher(enumDecl(unless(isMacro()), hasSequentialInitialValues()) + .bind("sequential"), + this); +} + +void EnumInitialValueCheck::check(const MatchFinder::MatchResult &Result) { + if (const auto *Enum = Result.Nodes.getNodeAs<EnumDecl>("inconsistent")) { + DiagnosticBuilder Diag = + diag(Enum->getBeginLoc(), + "inital values in enum %0 are not consistent, consider explicit " + "initialization of all, none or only the first enumerator") + << Enum; + for (const EnumConstantDecl *ECD : Enum->enumerators()) + if (ECD->getInitExpr() == nullptr) { + const SourceLocation EndLoc = Lexer::getLocForEndOfToken( + ECD->getLocation(), 0, *Result.SourceManager, getLangOpts()); + if (EndLoc.isMacroID()) + continue; + llvm::SmallString<8> Str{" = "}; + ECD->getInitVal().toString(Str); + Diag << FixItHint::CreateInsertion(EndLoc, Str); + } + return; + } + + if (const auto *Enum = Result.Nodes.getNodeAs<EnumDecl>("zero_first")) { + const EnumConstantDecl *ECD = *Enum->enumerator_begin(); + const SourceLocation Loc = ECD->getLocation(); + if (Loc.isInvalid() || Loc.isMacroID()) + return; + DiagnosticBuilder Diag = diag(Loc, "zero initial value for the first " + "enumerator in %0 can be disregarded") + << Enum; + cleanInitialValue(Diag, ECD, *Result.SourceManager, getLangOpts()); + return; + } + if (const auto *Enum = Result.Nodes.getNodeAs<EnumDecl>("sequential")) { + DiagnosticBuilder Diag = + diag(Enum->getBeginLoc(), + "sequential initial value in %0 can be ignored") + << Enum; + for (const EnumConstantDecl *ECD : llvm::drop_begin(Enum->enumerators())) + cleanInitialValue(Diag, ECD, *Result.SourceManager, getLangOpts()); + return; + } +} + +} // namespace clang::tidy::readability diff --git a/clang-tools-extra/clang-tidy/readability/EnumInitialValueCheck.h b/clang-tools-extra/clang-tidy/readability/EnumInitialValueCheck.h new file mode 100644 index 00000000000000..66087e4ee170da --- /dev/null +++ b/clang-tools-extra/clang-tidy/readability/EnumInitialValueCheck.h @@ -0,0 +1,38 @@ +//===--- EnumInitialValueCheck.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_ENUMINITIALVALUECHECK_H +#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_ENUMINITIALVALUECHECK_H + +#include "../ClangTidyCheck.h" + +namespace clang::tidy::readability { + +/// Enforces consistent style for enumerators' initialization, covering three +/// styles: none, first only, or all initialized explicitly. +/// +/// For the user-facing documentation see: +/// http://clang.llvm.org/extra/clang-tidy/checks/readability/enum-initial-value.html +class EnumInitialValueCheck : public ClangTidyCheck { +public: + EnumInitialValueCheck(StringRef Name, ClangTidyContext *Context); + void storeOptions(ClangTidyOptions::OptionMap &Opts) override; + void registerMatchers(ast_matchers::MatchFinder *Finder) override; + void check(const ast_matchers::MatchFinder::MatchResult &Result) override; + std::optional<TraversalKind> getCheckTraversalKind() const override { + return TK_IgnoreUnlessSpelledInSource; + } + +private: + const bool AllowExplicitZeroFirstInitialValue; + const bool AllowExplicitSequentialInitialValues; +}; + +} // namespace clang::tidy::readability + +#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_ENUMINITIALVALUECHECK_H diff --git a/clang-tools-extra/clang-tidy/readability/ReadabilityTidyModule.cpp b/clang-tools-extra/clang-tidy/readability/ReadabilityTidyModule.cpp index bca2c425111f6c..376b84683df74e 100644 --- a/clang-tools-extra/clang-tidy/readability/ReadabilityTidyModule.cpp +++ b/clang-tools-extra/clang-tidy/readability/ReadabilityTidyModule.cpp @@ -22,6 +22,7 @@ #include "DeleteNullPointerCheck.h" #include "DuplicateIncludeCheck.h" #include "ElseAfterReturnCheck.h" +#include "EnumInitialValueCheck.h" #include "FunctionCognitiveComplexityCheck.h" #include "FunctionSizeCheck.h" #include "IdentifierLengthCheck.h" @@ -92,6 +93,8 @@ class ReadabilityModule : public ClangTidyModule { "readability-duplicate-include"); CheckFactories.registerCheck<ElseAfterReturnCheck>( "readability-else-after-return"); + CheckFactories.registerCheck<EnumInitialValueCheck>( + "readability-enum-initial-value"); CheckFactories.registerCheck<FunctionCognitiveComplexityCheck>( "readability-function-cognitive-complexity"); CheckFactories.registerCheck<FunctionSizeCheck>( diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst index 78b09d23d4427f..309b844615a121 100644 --- a/clang-tools-extra/docs/ReleaseNotes.rst +++ b/clang-tools-extra/docs/ReleaseNotes.rst @@ -123,6 +123,12 @@ New checks Finds initializer lists for aggregate types that could be written as designated initializers instead. +- New :doc:`readability-enum-initial-value + <clang-tidy/checks/readability/enum-initial-value>` check. + + Enforces consistent style for enumerators' initialization, covering three + styles: none, first only, or all initialized explicitly. + - New :doc:`readability-use-std-min-max <clang-tidy/checks/readability/use-std-min-max>` check. diff --git a/clang-tools-extra/docs/clang-tidy/checks/list.rst b/clang-tools-extra/docs/clang-tidy/checks/list.rst index 79e81dd174e4f3..188a42bfddd383 100644 --- a/clang-tools-extra/docs/clang-tidy/checks/list.rst +++ b/clang-tools-extra/docs/clang-tidy/checks/list.rst @@ -352,6 +352,7 @@ Clang-Tidy Checks :doc:`readability-delete-null-pointer <readability/delete-null-pointer>`, "Yes" :doc:`readability-duplicate-include <readability/duplicate-include>`, "Yes" :doc:`readability-else-after-return <readability/else-after-return>`, "Yes" + :doc:`readability-enum-initial-value <readability/enum-initial-value>`, "Yes" :doc:`readability-function-cognitive-complexity <readability/function-cognitive-complexity>`, :doc:`readability-function-size <readability/function-size>`, :doc:`readability-identifier-length <readability/identifier-length>`, diff --git a/clang-tools-extra/docs/clang-tidy/checks/readability/enum-initial-value.rst b/clang-tools-extra/docs/clang-tidy/checks/readability/enum-initial-value.rst new file mode 100644 index 00000000000000..660efc1eaff3e5 --- /dev/null +++ b/clang-tools-extra/docs/clang-tidy/checks/readability/enum-initial-value.rst @@ -0,0 +1,75 @@ +.. title:: clang-tidy - readability-enum-initial-value + +readability-enum-initial-value +============================== + +Enforces consistent style for enumerators' initialization, covering three +styles: none, first only, or all initialized explicitly. + +When adding new enumerations, inconsistent initial value will cause potential +enumeration value conflicts. + +In an enumeration, the following three cases are accepted. +1. none of enumerators are explicit initialized. +2. the first enumerator is explicit initialized. +3. all of enumerators are explicit initialized. + +.. code-block:: c++ + + // valid, none of enumerators are initialized. + enum A { + e0, + e1, + e2, + }; + + // valid, the first enumerator is initialized. + enum A { + e0 = 0, + e1, + e2, + }; + + // valid, all of enumerators are initialized. + enum A { + e0 = 0, + e1 = 1, + e2 = 2, + }; + + // invalid, e1 is not explicit initialized. + enum A { + e0 = 0, + e1, + e2 = 2, + }; + +Options +------- + +.. option:: AllowExplicitZeroFirstInitialValue + + If set to `false`, the first enumerator must not be explicitly initialized. + See examples below. Default is `true`. + + .. code-block:: c++ + + enum A { + e0 = 0, // not allowed if AllowExplicitZeroFirstInitialValue is false + e1, + e2, + }; + + +.. option:: AllowExplicitSequentialInitialValues + + If set to `false`, sequential initializations are not allowed. + See examples below. Default is `true`. + + .. code-block:: c++ + + enum A { + e0 = 1, // not allowed if AllowExplicitSequentialInitialValues is false + e1 = 2, + e2 = 3, + }; diff --git a/clang-tools-extra/test/clang-tidy/checkers/readability/enum-initial-value.c b/clang-tools-extra/test/clang-tidy/checkers/readability/enum-initial-value.c new file mode 100644 index 00000000000000..c66288cbe3e957 --- /dev/null +++ b/clang-tools-extra/test/clang-tidy/checkers/readability/enum-initial-value.c @@ -0,0 +1,80 @@ +// RUN: %check_clang_tidy %s readability-enum-initial-value %t +// RUN: %check_clang_tidy -check-suffix=ENABLE %s readability-enum-initial-value %t -- \ +// RUN: -config='{CheckOptions: { \ +// RUN: readability-enum-initial-value.AllowExplicitZeroFirstInitialValue: false, \ +// RUN: readability-enum-initial-value.AllowExplicitSequentialInitialValues: false, \ +// RUN: }}' + +enum EError { + // CHECK-MESSAGES: :[[@LINE-1]]:1: warning: inital values in enum 'EError' are not consistent + // CHECK-MESSAGES-ENABLE: :[[@LINE-2]]:1: warning: inital values in enum 'EError' are not consistent + EError_a = 1, + EError_b, + // CHECK-FIXES: EError_b = 2, + EError_c = 3, +}; + +enum ENone { + ENone_a, + ENone_b, + EENone_c, +}; + +enum EFirst { + EFirst_a = 1, + EFirst_b, + EFirst_c, +}; + +enum EAll { + EAll_a = 1, + EAll_b = 2, + EAll_c = 4, +}; + +#define ENUMERATOR_1 EMacro1_b +enum EMacro1 { + // CHECK-MESSAGES: :[[@LINE-1]]:1: warning: inital values in enum 'EMacro1' are not consistent + // CHECK-MESSAGES-ENABLE: :[[@LINE-2]]:1: warning: inital values in enum 'EMacro1' are not consistent + EMacro1_a = 1, + ENUMERATOR_1, + // CHECK-FIXES: ENUMERATOR_1 = 2, + EMacro1_c = 3, +}; + + +#define ENUMERATOR_2 EMacro2_b = 2 +enum EMacro2 { + // CHECK-MESSAGES: :[[@LINE-1]]:1: warning: inital values in enum 'EMacro2' are not consistent + // CHECK-MESSAGES-ENABLE: :[[@LINE-2]]:1: warning: inital values in enum 'EMacro2' are not consistent + EMacro2_a = 1, + ENUMERATOR_2, + EMacro2_c, + // CHECK-FIXES: EMacro2_c = 3, +}; + +enum EnumZeroFirstInitialValue { + EnumZeroFirstInitialValue_0 = 0, + // CHECK-MESSAGES-ENABLE: :[[@LINE-1]]:3: warning: zero initial value for the first enumerator in 'EnumZeroFirstInitialValue' can be disregarded + // CHECK-FIXES-ENABLE: EnumZeroFirstInitialValue_0 , + EnumZeroFirstInitialValue_1, + EnumZeroFirstInitialValue_2, +}; + +enum EnumZeroFirstInitialValueWithComment { + EnumZeroFirstInitialValueWithComment_0 = /* == */ 0, + // CHECK-MESSAGES-ENABLE: :[[@LINE-1]]:3: warning: zero initial value for the first enumerator in 'EnumZeroFirstInitialValueWithComment' can be disregarded + // CHECK-FIXES-ENABLE: EnumZeroFirstInitialValueWithComment_0 /* == */ , + EnumZeroFirstInitialValueWithComment_1, + EnumZeroFirstInitialValueWithComment_2, +}; + +enum EnumSequentialInitialValue { + // CHECK-MESSAGES-ENABLE: :[[@LINE-1]]:1: warning: sequential initial value in 'EnumSequentialInitialValue' can be ignored + EnumSequentialInitialValue_0 = 2, + // CHECK-FIXES-ENABLE: EnumSequentialInitialValue_0 = 2, + EnumSequentialInitialValue_1 = 3, + // CHECK-FIXES-ENABLE: EnumSequentialInitialValue_1 , + EnumSequentialInitialValue_2 = 4, + // CHECK-FIXES-ENABLE: EnumSequentialInitialValue_2 , +}; diff --git a/clang-tools-extra/test/clang-tidy/checkers/readability/enum-initial-value.cpp b/clang-tools-extra/test/clang-tidy/checkers/readability/enum-initial-value.cpp new file mode 100644 index 00000000000000..3c4ba970372a07 --- /dev/null +++ b/clang-tools-extra/test/clang-tidy/checkers/readability/enum-initial-value.cpp @@ -0,0 +1,27 @@ +// RUN: %check_clang_tidy %s readability-enum-initial-value %t + +enum class EError { + // CHECK-MESSAGES: :[[@LINE-1]]:1: warning: inital values in enum 'EError' are not consistent + EError_a = 1, + EError_b, + // CHECK-FIXES: EError_b = 2, + EError_c = 3, +}; + +enum class ENone { + ENone_a, + ENone_b, + EENone_c, +}; + +enum class EFirst { + EFirst_a = 1, + EFirst_b, + EFirst_c, +}; + +enum class EAll { + EAll_a = 1, + EAll_b = 2, + EAll_c = 3, +}; _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
