Tooling.h | Explore in Territory

//===- Tooling.h - Framework for standalone Clang tools ---------*- 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
//
//===----------------------------------------------------------------------===//
//
//  This file implements functions to run clang tools standalone instead
//  of running them as a plugin.
//
//  A ClangTool is initialized with a CompilationDatabase and a set of files
//  to run over. The tool will then run a user-specified FrontendAction over
//  all TUs in which the given files are compiled.
//
//  It is also possible to run a FrontendAction over a snippet of code by
//  calling runToolOnCode, which is useful for unit testing.
//
//  Applications that need more fine grained control over how to run
//  multiple FrontendActions over code can use ToolInvocation.
//
//  Example tools:
//  - running clang -fsyntax-only over source code from an editor to get
//    fast syntax checks
//  - running match/replace tools over C++ code
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_TOOLING_TOOLING_H
#define LLVM_CLANG_TOOLING_TOOLING_H

#include "clang/AST/ASTConsumer.h"
#include "clang/Basic/FileManager.h"
#include "clang/Basic/LLVM.h"
#include "clang/Frontend/FrontendAction.h"
#include "clang/Frontend/PCHContainerOperations.h"
#include "clang/Tooling/ArgumentsAdjusters.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/IntrusiveRefCntPtr.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/StringSet.h"
#include "llvm/ADT/Twine.h"
#include "llvm/Option/Option.h"
#include "llvm/Support/VirtualFileSystem.h"
#include <memory>
#include <string>
#include <utility>
#include <vector>

namespace clang {

class CompilerInstance;
class CompilerInvocation;
class DiagnosticConsumer;
class DiagnosticsEngine;

namespace driver {

class Compilation;

} // namespace driver

namespace tooling {

class CompilationDatabase;

/// Retrieves the flags of the `-cc1` job in `Compilation` that has only source
/// files as its inputs.
/// Returns nullptr if there are no such jobs or multiple of them. Note that
/// offloading jobs are ignored.
const llvm::opt::ArgStringList *
getCC1Arguments(DiagnosticsEngine *Diagnostics,
                driver::Compilation *Compilation);

/// Interface to process a clang::CompilerInvocation.
///
/// If your tool is based on FrontendAction, you should be deriving from
/// FrontendActionFactory instead.
class ToolAction { … };

/// Interface to generate clang::FrontendActions.
///
/// Having a factory interface allows, for example, a new FrontendAction to be
/// created for each translation unit processed by ClangTool.  This class is
/// also a ToolAction which uses the FrontendActions created by create() to
/// process each translation unit.
class FrontendActionFactory : public ToolAction { … };

/// Returns a new FrontendActionFactory for a given type.
///
/// T must derive from clang::FrontendAction.
///
/// Example:
/// std::unique_ptr<FrontendActionFactory> Factory =
///   newFrontendActionFactory<clang::SyntaxOnlyAction>();
template <typename T>
std::unique_ptr<FrontendActionFactory> newFrontendActionFactory();

/// Callbacks called before and after each source file processed by a
/// FrontendAction created by the FrontedActionFactory returned by \c
/// newFrontendActionFactory.
class SourceFileCallbacks { … };

/// Returns a new FrontendActionFactory for any type that provides an
/// implementation of newASTConsumer().
///
/// FactoryT must implement: ASTConsumer *newASTConsumer().
///
/// Example:
/// struct ProvidesASTConsumers {
///   std::unique_ptr<clang::ASTConsumer> newASTConsumer();
/// } Factory;
/// std::unique_ptr<FrontendActionFactory> FactoryAdapter(
///   newFrontendActionFactory(&Factory));
template <typename FactoryT>
inline std::unique_ptr<FrontendActionFactory> newFrontendActionFactory(
    FactoryT *ConsumerFactory, SourceFileCallbacks *Callbacks = nullptr);

/// Runs (and deletes) the tool on 'Code' with the -fsyntax-only flag.
///
/// \param ToolAction The action to run over the code.
/// \param Code C++ code.
/// \param FileName The file name which 'Code' will be mapped as.
/// \param PCHContainerOps  The PCHContainerOperations for loading and creating
///                         clang modules.
///
/// \return - True if 'ToolAction' was successfully executed.
bool runToolOnCode(std::unique_ptr<FrontendAction> ToolAction, const Twine &Code,
                   const Twine &FileName = "input.cc",
                   std::shared_ptr<PCHContainerOperations> PCHContainerOps =
                       std::make_shared<PCHContainerOperations>());

/// The first part of the pair is the filename, the second part the
/// file-content.
FileContentMappings;

/// Runs (and deletes) the tool on 'Code' with the -fsyntax-only flag and
///        with additional other flags.
///
/// \param ToolAction The action to run over the code.
/// \param Code C++ code.
/// \param Args Additional flags to pass on.
/// \param FileName The file name which 'Code' will be mapped as.
/// \param ToolName The name of the binary running the tool. Standard library
///                 header paths will be resolved relative to this.
/// \param PCHContainerOps   The PCHContainerOperations for loading and creating
///                          clang modules.
///
/// \return - True if 'ToolAction' was successfully executed.
bool runToolOnCodeWithArgs(
    std::unique_ptr<FrontendAction> ToolAction, const Twine &Code,
    const std::vector<std::string> &Args, const Twine &FileName = "input.cc",
    const Twine &ToolName = "clang-tool",
    std::shared_ptr<PCHContainerOperations> PCHContainerOps =
        std::make_shared<PCHContainerOperations>(),
    const FileContentMappings &VirtualMappedFiles = FileContentMappings());

// Similar to the overload except this takes a VFS.
bool runToolOnCodeWithArgs(
    std::unique_ptr<FrontendAction> ToolAction, const Twine &Code,
    llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS,
    const std::vector<std::string> &Args, const Twine &FileName = "input.cc",
    const Twine &ToolName = "clang-tool",
    std::shared_ptr<PCHContainerOperations> PCHContainerOps =
        std::make_shared<PCHContainerOperations>());

/// Builds an AST for 'Code'.
///
/// \param Code C++ code.
/// \param FileName The file name which 'Code' will be mapped as.
/// \param PCHContainerOps The PCHContainerOperations for loading and creating
/// clang modules.
///
/// \return The resulting AST or null if an error occurred.
std::unique_ptr<ASTUnit>
buildASTFromCode(StringRef Code, StringRef FileName = "input.cc",
                 std::shared_ptr<PCHContainerOperations> PCHContainerOps =
                     std::make_shared<PCHContainerOperations>());

/// Builds an AST for 'Code' with additional flags.
///
/// \param Code C++ code.
/// \param Args Additional flags to pass on.
/// \param FileName The file name which 'Code' will be mapped as.
/// \param ToolName The name of the binary running the tool. Standard library
///                 header paths will be resolved relative to this.
/// \param PCHContainerOps The PCHContainerOperations for loading and creating
/// clang modules.
///
/// \param Adjuster A function to filter the command line arguments as specified.
///
/// \return The resulting AST or null if an error occurred.
std::unique_ptr<ASTUnit> buildASTFromCodeWithArgs(
    StringRef Code, const std::vector<std::string> &Args,
    StringRef FileName = "input.cc", StringRef ToolName = "clang-tool",
    std::shared_ptr<PCHContainerOperations> PCHContainerOps =
        std::make_shared<PCHContainerOperations>(),
    ArgumentsAdjuster Adjuster = getClangStripDependencyFileAdjuster(),
    const FileContentMappings &VirtualMappedFiles = FileContentMappings(),
    DiagnosticConsumer *DiagConsumer = nullptr);

/// Utility to run a FrontendAction in a single clang invocation.
class ToolInvocation { … };

/// Utility to run a FrontendAction over a set of files.
///
/// This class is written to be usable for command line utilities.
/// By default the class uses ClangSyntaxOnlyAdjuster to modify
/// command line arguments before the arguments are used to run
/// a frontend action. One could install an additional command line
/// arguments adjuster by calling the appendArgumentsAdjuster() method.
class ClangTool { … };

template <typename T>
std::unique_ptr<FrontendActionFactory> newFrontendActionFactory() { … }

template <typename FactoryT>
inline std::unique_ptr<FrontendActionFactory> newFrontendActionFactory(
    FactoryT *ConsumerFactory, SourceFileCallbacks *Callbacks) { … }

/// Returns the absolute path of \c File, by prepending it with
/// the current directory if \c File is not absolute.
///
/// Otherwise returns \c File.
/// If 'File' starts with "./", the returned path will not contain the "./".
/// Otherwise, the returned path will contain the literal path-concatenation of
/// the current directory and \c File.
///
/// The difference to llvm::sys::fs::make_absolute is the canonicalization this
/// does by removing "./" and computing native paths.
///
/// \param File Either an absolute or relative path.
std::string getAbsolutePath(StringRef File);

/// An overload of getAbsolutePath that works over the provided \p FS.
llvm::Expected<std::string> getAbsolutePath(llvm::vfs::FileSystem &FS,
                                            StringRef File);

/// Changes CommandLine to contain implicit flags that would have been
/// defined had the compiler driver been invoked through the path InvokedAs.
///
/// For example, when called with \c InvokedAs set to `i686-linux-android-g++`,
/// the arguments '-target', 'i686-linux-android`, `--driver-mode=g++` will
/// be inserted after the first argument in \c CommandLine.
///
/// This function will not add new `-target` or `--driver-mode` flags if they
/// are already present in `CommandLine` (even if they have different settings
/// than would have been inserted).
///
/// \pre `llvm::InitializeAllTargets()` has been called.
///
/// \param CommandLine the command line used to invoke the compiler driver or
/// Clang tool, including the path to the executable as \c CommandLine[0].
/// \param InvokedAs the path to the driver used to infer implicit flags.
///
/// \note This will not set \c CommandLine[0] to \c InvokedAs. The tooling
/// infrastructure expects that CommandLine[0] is a tool path relative to which
/// the builtin headers can be found.
void addTargetAndModeForProgramName(std::vector<std::string> &CommandLine,
                                    StringRef InvokedAs);

/// Helper function that expands response files in command line.
void addExpandedResponseFiles(std::vector<std::string> &CommandLine,
                              llvm::StringRef WorkingDir,
                              llvm::cl::TokenizerCallback Tokenizer,
                              llvm::vfs::FileSystem &FS);

/// Creates a \c CompilerInvocation.
CompilerInvocation *newInvocation(DiagnosticsEngine *Diagnostics,
                                  ArrayRef<const char *> CC1Args,
                                  const char *const BinaryName);

} // namespace tooling

} // namespace clang

#endif // LLVM_CLANG_TOOLING_TOOLING_H
llvm/clang/include/clang/Tooling/Tooling.h
