llvm/clang-tools-extra/clang-tidy/readability/IsolateDeclarationCheck.cpp

//===--- IsolateDeclarationCheck.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 "IsolateDeclarationCheck.h"
#include "../utils/LexerUtils.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"
#include <optional>

usingnamespaceclang::ast_matchers;
usingnamespaceclang::tidy::utils::lexer;

namespace clang::tidy::readability {

namespace {
AST_MATCHER(DeclStmt, isSingleDecl) { … }
AST_MATCHER(DeclStmt, onlyDeclaresVariables) { … }
} // namespace

void IsolateDeclarationCheck::registerMatchers(MatchFinder *Finder) { … }

static SourceLocation findStartOfIndirection(SourceLocation Start,
                                             int Indirections,
                                             const SourceManager &SM,
                                             const LangOptions &LangOpts) { … }

static bool isMacroID(SourceRange R) { … }

/// This function counts the number of written indirections for the given
/// Type \p T. It does \b NOT resolve typedefs as it's a helper for lexing
/// the source code.
/// \see declRanges
static int countIndirections(const Type *T, int Indirections = 0) { … }

static bool typeIsMemberPointer(const Type *T) { … }

/// This function tries to extract the SourceRanges that make up all
/// declarations in this \c DeclStmt.
///
/// The resulting vector has the structure {UnderlyingType, Decl1, Decl2, ...}.
/// Each \c SourceRange is of the form [Begin, End).
/// If any of the create ranges is invalid or in a macro the result will be
/// \c None.
/// If the \c DeclStmt contains only one declaration, the result is \c None.
/// If the \c DeclStmt contains declarations other than \c VarDecl the result
/// is \c None.
///
/// \code
///    int * ptr1 = nullptr, value = 42;
/// // [  ][              ] [         ] - The ranges here are inclusive
/// \endcode
/// \todo Generalize this function to take other declarations than \c VarDecl.
static std::optional<std::vector<SourceRange>>
declRanges(const DeclStmt *DS, const SourceManager &SM,
           const LangOptions &LangOpts) { … }

static std::optional<std::vector<StringRef>>
collectSourceRanges(llvm::ArrayRef<SourceRange> Ranges, const SourceManager &SM,
                    const LangOptions &LangOpts) { … }

/// Expects a vector {TypeSnippet, Firstdecl, SecondDecl, ...}.
static std::vector<std::string>
createIsolatedDecls(llvm::ArrayRef<StringRef> Snippets) { … }

void IsolateDeclarationCheck::check(const MatchFinder::MatchResult &Result) { … }
} // namespace clang::tidy::readability