Index: clang-tidy/readability/CMakeLists.txt =================================================================== --- clang-tidy/readability/CMakeLists.txt +++ clang-tidy/readability/CMakeLists.txt @@ -11,6 +11,7 @@ IdentifierNamingCheck.cpp ImplicitBoolConversionCheck.cpp InconsistentDeclarationParameterNameCheck.cpp + IsolateDeclCheck.cpp MagicNumbersCheck.cpp MisleadingIndentationCheck.cpp MisplacedArrayIndexCheck.cpp Index: clang-tidy/readability/IsolateDeclCheck.h =================================================================== --- /dev/null +++ clang-tidy/readability/IsolateDeclCheck.h @@ -0,0 +1,35 @@ +//===--- IsolateDeclCheck.h - clang-tidy-------------------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_ISOLATEDECLCHECK_H +#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_ISOLATEDECLCHECK_H + +#include "../ClangTidy.h" + +namespace clang { +namespace tidy { +namespace readability { + +/// FIXME: Write a short description. +/// +/// For the user-facing documentation see: +/// http://clang.llvm.org/extra/clang-tidy/checks/readability-isolate-decl.html +class IsolateDeclCheck : public ClangTidyCheck { +public: + IsolateDeclCheck(StringRef Name, ClangTidyContext *Context) + : ClangTidyCheck(Name, Context) {} + void registerMatchers(ast_matchers::MatchFinder *Finder) override; + void check(const ast_matchers::MatchFinder::MatchResult &Result) override; +}; + +} // namespace readability +} // namespace tidy +} // namespace clang + +#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_ISOLATEDECLCHECK_H Index: clang-tidy/readability/IsolateDeclCheck.cpp =================================================================== --- /dev/null +++ clang-tidy/readability/IsolateDeclCheck.cpp @@ -0,0 +1,205 @@ +//===--- IsolateDeclCheck.cpp - clang-tidy---------------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "IsolateDeclCheck.h" +#include "clang/AST/ASTContext.h" +#include "clang/ASTMatchers/ASTMatchFinder.h" +#include "clang/Lex/Lexer.h" + +#include +#include + +using namespace clang::ast_matchers; + +#define PRINT_DEBUG 0 + +namespace clang { +namespace tidy { +namespace readability { + +namespace { +AST_MATCHER(DeclStmt, isSingleDecl) { return Node.isSingleDecl(); } +} // namespace + +void IsolateDeclCheck::registerMatchers(MatchFinder *Finder) { + Finder->addMatcher(declStmt(unless(isSingleDecl())).bind("decl_stmt"), this); +} + +namespace { +SourceLocation findNextTerminator(SourceLocation Start, const SourceManager &SM, + const LangOptions &LangOpts) { + while (true) { + Optional CurrentToken = Lexer::findNextToken(Start, SM, LangOpts); + assert(CurrentToken.hasValue() && "Could not find token in Decl"); + Token PotentialComma = *CurrentToken; + + if (PotentialComma.getKind() == tok::comma || + PotentialComma.getKind() == tok::semi) + return PotentialComma.getLocation(); + + Start = + Lexer::getLocForEndOfToken(Start, 0, SM, LangOpts).getLocWithOffset(1); + } +} + +/// This function goes back in the source text, to find the beginning of +/// indirection. +/// Necessary for `int *p, i;` where `p` has one level of indirection. +/// To isolate the decl properly, the first Slice must only be `int` and not +/// `int *`. +SourceLocation findStartOfIndirection(SourceLocation Start, + const SourceManager &SM, + const LangOptions &LangOpts) { + while (true) { + Optional CurrentToken = Lexer::findNextToken(Start, SM, LangOpts); + assert(CurrentToken.hasValue() && "Could not find token in Decl"); + Token PotentialIndirection = *CurrentToken; + + if (PotentialIndirection.getKind() == tok::star || + PotentialIndirection.getKind() == tok::amp) + return PotentialIndirection.getLocation(); + + Start = + Lexer::getLocForEndOfToken(Start, 0, SM, LangOpts).getLocWithOffset(1); + } +} + +/// This function assumes, that \p DS only contains VarDecl elements. +std::vector DeclSlice(const DeclStmt *DS, const SourceManager &SM, + const LangOptions &LangOpts) { + // The initial type of the declaration and each declaration has it's slice. + std::vector Slices; + Slices.reserve(std::distance(DS->decl_begin(), DS->decl_end()) + 1); +#if PRINT_DEBUG + std::cerr << "Number of Slices to create: " << Slices.capacity() << "\n"; +#endif + assert(Slices.capacity() > 2 && + "Expect at least 3 sections (type, first decl, second decl) "); + + // Special case for the type where the SourceRange is computed + // differently. + VarDecl *FirstDecl = dyn_cast(*DS->decl_begin()); + assert(FirstDecl && "Expect only VarDecls"); + + SourceLocation Start; + if (FirstDecl->getType()->isPointerType() || + FirstDecl->getType()->isReferenceType()) + Start = findStartOfIndirection(DS->getBeginLoc(), SM, LangOpts); + else + Start = FirstDecl->getLocation(); + +#if PRINT_DEBUG + std::cerr << "Start of Indirection: " << Start.printToString(SM) << "\n"; +#endif + Slices.emplace_back(SourceRange(DS->getBeginLoc(), Start)); + + SourceLocation DeclBegin = Start; + for (auto It = DS->decl_begin(), End = DS->decl_end(); It != End; ++It) { + VarDecl *CurrentDecl = dyn_cast(*It); + assert(CurrentDecl && "Expect only VarDecls here"); + + SourceLocation DeclEnd; + if (CurrentDecl->hasInit()) + DeclEnd = + findNextTerminator(CurrentDecl->getInit()->getEndLoc(), SM, LangOpts); + else + DeclEnd = findNextTerminator(CurrentDecl->getEndLoc(), SM, LangOpts); + +#if PRINT_DEBUG + std::cerr << "Start of Slice: " << DeclBegin.printToString(SM) << "\n"; + std::cerr << "End of Slice: " << DeclEnd.printToString(SM) << "\n"; +#endif + Slices.emplace_back(SourceRange(DeclBegin, DeclEnd)); + DeclBegin = DeclEnd.getLocWithOffset(1); + } + + return Slices; +} + +std::vector SourceFromRanges(const std::vector &Ranges, + const SourceManager &SM, + const LangOptions &LangOpts) { + std::vector Snippets; + Snippets.reserve(Ranges.size()); + + for (const auto &Range : Ranges) { + CharSourceRange CR = Lexer::getAsCharRange( + CharSourceRange::getCharRange(Range.getBegin(), Range.getEnd()), SM, + LangOpts); + assert(CR.isValid() && "Retrieved invalid char source range"); + + bool InvalidText = false; + StringRef Snippet = Lexer::getSourceText(CR, SM, LangOpts, &InvalidText); + assert(!InvalidText && "Retrieved invalid text"); + + Snippets.emplace_back(Snippet); + } + + return Snippets; +} + +/// Excepts a vector {TypeSnippet, Firstdecl, SecondDecl, ...}. +std::vector +CreateIsolatedDecls(const std::vector &Snippets) { + // The first section is the type snippet, which does not make a decl itself. + assert(Snippets.size() >= 2 && "No enough snippets to create isolated decls"); + std::vector Decls(Snippets.size() - 1); + + for (std::size_t i = 1, End = Snippets.size(); i < End; ++i) + Decls[i - 1] = Snippets[0].str() + Snippets[i].ltrim().str(); + + return Decls; +} + +std::string &TrimRight(std::string &str) { + auto it1 = std::find_if(str.rbegin(), str.rend(), [](char ch) { + return !std::isspace(ch, std::locale::classic()); + }); + str.erase(it1.base(), str.end()); + return str; +} + +std::string Concat(const std::vector &Decls, StringRef Indent) { + std::string R; + for (const std::string &D : Decls) + R += D + ";\n" + Indent.str(); + return TrimRight(R); +} + +} // namespace + +void IsolateDeclCheck::check(const MatchFinder::MatchResult &Result) { + const auto *WholeDecl = Result.Nodes.getNodeAs("decl_stmt"); + + std::vector Slices = + DeclSlice(WholeDecl, *Result.SourceManager, getLangOpts()); +#if PRINT_DEBUG + std::cerr << "Number of Slices: " << Slices.size() << "\n"; + for (const auto &Slice : Slices) { + diag(Slice.getBegin(), "Slice start", DiagnosticIDs::Note); + diag(Slice.getEnd(), "Slice End", DiagnosticIDs::Note); + } +#endif + + std::vector Snippets = + SourceFromRanges(Slices, *Result.SourceManager, getLangOpts()); + + std::vector NewDecls = CreateIsolatedDecls(Snippets); + std::string Replacement = + Concat(NewDecls, Lexer::getIndentationForLine(WholeDecl->getBeginLoc(), + *Result.SourceManager)); + + std::cerr << Replacement << "\n"; + + diag(WholeDecl->getBeginLoc(), "make only one declaration per statement") + << FixItHint::CreateReplacement(WholeDecl->getSourceRange(), Replacement); +} +} // namespace readability +} // namespace tidy +} // namespace clang Index: clang-tidy/readability/ReadabilityTidyModule.cpp =================================================================== --- clang-tidy/readability/ReadabilityTidyModule.cpp +++ clang-tidy/readability/ReadabilityTidyModule.cpp @@ -20,6 +20,7 @@ #include "IdentifierNamingCheck.h" #include "ImplicitBoolConversionCheck.h" #include "InconsistentDeclarationParameterNameCheck.h" +#include "IsolateDeclCheck.h" #include "MagicNumbersCheck.h" #include "MisleadingIndentationCheck.h" #include "MisplacedArrayIndexCheck.h" @@ -66,6 +67,8 @@ "readability-implicit-bool-conversion"); CheckFactories.registerCheck( "readability-inconsistent-declaration-parameter-name"); + CheckFactories.registerCheck( + "readability-isolate-decl"); CheckFactories.registerCheck( "readability-magic-numbers"); CheckFactories.registerCheck( Index: docs/ReleaseNotes.rst =================================================================== --- docs/ReleaseNotes.rst +++ docs/ReleaseNotes.rst @@ -93,6 +93,11 @@ Flags uses of ``absl::StrCat()`` to append to a ``std::string``. Suggests ``absl::StrAppend()`` should be used instead. +- New :doc:`readability-isolate-decl + ` check. + + FIXME: add release notes. + - New :doc:`readability-magic-numbers ` check. Index: docs/clang-tidy/checks/list.rst =================================================================== --- docs/clang-tidy/checks/list.rst +++ docs/clang-tidy/checks/list.rst @@ -225,6 +225,7 @@ readability-identifier-naming readability-implicit-bool-conversion readability-inconsistent-declaration-parameter-name + readability-isolate-decl readability-magic-numbers readability-misleading-indentation readability-misplaced-array-index Index: docs/clang-tidy/checks/readability-isolate-decl.rst =================================================================== --- /dev/null +++ docs/clang-tidy/checks/readability-isolate-decl.rst @@ -0,0 +1,6 @@ +.. title:: clang-tidy - readability-isolate-decl + +readability-isolate-decl +======================== + +FIXME: Describe what patterns does the check detect and why. Give examples. Index: test/clang-tidy/readability-isolate-decl.cpp =================================================================== --- /dev/null +++ test/clang-tidy/readability-isolate-decl.cpp @@ -0,0 +1,82 @@ +// RUN: %check_clang_tidy %s readability-isolate-decl %t + +void f() { + int i; +} + +void f2() { + int i, j, *k, lala = 42; + // CHECK-MESSAGES: [[@LINE-1]]:3: warning: make only one declaration per statement + // CHECK-FIXES: int i; + // CHECK-FIXES: {{^ }}int j; + // CHECK-FIXES: {{^ }}int *k; + // CHECK-FIXES: {{^ }}int lala = 42; + + int normal, weird = /* comment */ 42; + // CHECK-MESSAGES: [[@LINE-1]]:3: warning: make only one declaration per statement + // CHECK-FIXES: int normal; + // CHECK-FIXES: {{^ }}int weird = /* comment */ 42; +} + +void f3() { + int i, *pointer1; + // CHECK-MESSAGES: [[@LINE-1]]:3: warning: make only one declaration per statement + // CHECK-FIXES: int i; + // CHECK-FIXES: {{^ }}int *pointer1; + // + int *pointer2 = nullptr, *pointer3 = &i; + // CHECK-MESSAGES: [[@LINE-1]]:3: warning: make only one declaration per statement + // CHECK-FIXES: int *pointer2 = nullptr; + // CHECK-FIXES: {{^ }}int *pointer3 = &i; +} + +void f4() { + double d = 42. /* foo */, z = 43., /* hi */ y, c /* */ /* */, l = 2.; + // CHECK-MESSAGES: [[@LINE-1]]:3: warning: make only one declaration per statement + // CHECK-FIXES: double d = 42. /* foo */; + // CHECK-FIXES: {{^ }}double z = 43.; + // CHECK-FIXES: {{^ }}double /* hi */ y; + // CHECK-FIXES: {{^ }}double c /* */ /* */; + // CHECK-FIXES: {{^ }}double l = 2.; +} + +struct SomeClass { + SomeClass() = default; + SomeClass(int value); +}; +void f5() { + SomeClass v1, v2(42), v3{42}, v4(42.5); + // CHECK-MESSAGES: [[@LINE-1]]:3: warning: make only one declaration per statement + // CHECK-FIXES: SomeClass v1; + // CHECK-FIXES: {{^ }}SomeClass v2(42); + // CHECK-FIXES: {{^ }}SomeClass v3{42}; + // CHECK-FIXES: {{^ }}SomeClass v4(42.5); + + SomeClass v5 = 42, *p1 = nullptr; + // CHECK-MESSAGES: [[@LINE-1]]:3: warning: make only one declaration per statement + // CHECK-FIXES: SomeClass v5 = 42; + // CHECK-FIXES: {{^ }}SomeClass *p1 = nullptr; +} + +void f6() { + int array1[] = {1, 2, 3, 4}, array2[] = {1, 2, 3}, value1, value2 = 42; + // CHECK-MESSAGES: [[@LINE-1]]:3: warning: make only one declaration per statement + // CHECK-FIXES: int array1[] = {1, 2, 3, 4}; + // CHECK-FIXES: {{^ }}int array2[] = {1, 2, 3}; + // CHECK-FIXES: {{^ }}int value1; + // CHECK-FIXES: {{^ }}int value2 = 42; +} + +template +struct TemplatedType { + TemplatedType() = default; + TemplatedType(T value); +}; + +void f7() { + TemplatedType TT1(42), TT2{42}, TT3; + // CHECK-MESSAGES: [[@LINE-1]]:3: warning: make only one declaration per statement + // CHECK-FIXES: TemplatedType TT1(42); + // CHECK-FIXES: {{^ }}TemplatedType TT2{42}; + // CHECK-FIXES: {{^ }}TemplatedType TT3; +}