Add parse_files() utility function

include/cppast/compile_config.hpp

@@ -104,6 +104,9 @@ namespace cppast
         {
         }
 
+        compile_config(const compile_config&) = default;
+        compile_config& operator=(const compile_config&) = default;
+
         ~compile_config() noexcept = default;
 
         void add_flag(std::string flag)

include/cppast/detail/intrusive_list.hpp

@@ -14,6 +14,8 @@
 
 namespace cppast
 {
+    class cpp_file;
+
     namespace detail
     {
         template <typename T>
@@ -122,22 +124,20 @@ namespace cppast
             intrusive_list() = default;
 
             //=== modifiers ===//
-            template <typename U>
+            template <
+                typename Dummy = T,
+                typename = typename std::enable_if<std::is_same<Dummy, cpp_file>::value>::type>
+            void push_back(std::unique_ptr<T> obj) noexcept
+            {
+                push_back_impl(std::move(obj));
+            }
+
+            template <
+                typename U,
+                typename = typename std::enable_if<!std::is_same<T, cpp_file>::value, U>::type>
             void push_back(const U& parent, std::unique_ptr<T> obj) noexcept
             {
-                DEBUG_ASSERT(obj != nullptr, detail::assert_handler{});
+                push_back_impl(std::move(obj));
-
-                if (last_)
-                {
-                    auto ptr = intrusive_list_access<T>::set_next(last_.value(), std::move(obj));
-                    last_    = type_safe::ref(*ptr);
-                }
-                else
-                {
-                    first_ = std::move(obj);
-                    last_  = type_safe::opt_ref(first_.get());
-                }
-
                 intrusive_list_access<T>::on_insert(last_.value(), parent);
             }
 
@@ -192,6 +192,22 @@ namespace cppast
             }
 
         private:
+            void push_back_impl(std::unique_ptr<T> obj)
+            {
+                DEBUG_ASSERT(obj != nullptr, detail::assert_handler{});
+
+                if (last_)
+                {
+                    auto ptr = intrusive_list_access<T>::set_next(last_.value(), std::move(obj));
+                    last_    = type_safe::ref(*ptr);
+                }
+                else
+                {
+                    first_ = std::move(obj);
+                    last_  = type_safe::opt_ref(first_.get());
+                }
+            }
+
             std::unique_ptr<T>         first_;
             type_safe::optional_ref<T> last_;
         };

include/cppast/libclang_parser.hpp

@@ -62,6 +62,16 @@ namespace cppast
             return *this;
         }
 
+        /// \returns Whether or not the database contains information about the given file.
+        /// \group has_config
+        bool has_config(const char* file_name) const;
+
+        /// \group has_config
+        bool has_config(const std::string& file_name) const
+        {
+            return has_config(file_name.c_str());
+        }
+
     private:
         using database = void*;
         database database_;
@@ -94,6 +104,9 @@ namespace cppast
         libclang_compile_config(const libclang_compilation_database& database,
                                 const std::string&                   file);
 
+        libclang_compile_config(const libclang_compile_config& other) = default;
+        libclang_compile_config& operator=(const libclang_compile_config& other) = default;
+
         /// \effects Sets the path to the location of the `clang++` binary and the version of that binary.
         /// \notes It will be used for preprocessing.
         void set_clang_binary(std::string binary, int major, int minor, int patch)
@@ -122,10 +135,21 @@ namespace cppast
         friend detail::libclang_compile_config_access;
     };
 
+    /// Finds a configuration for a given file.
+    ///
+    /// \returns If the database contains a configuration for the given file, returns that configuration.
+    /// Otherwise removes the file extension of the file and tries the same procedure
+    /// for common C++ header and source file extensions.
+    /// \notes This function is intended to be used as the basis for a `get_config` function of [cppast::parse_files](standardese://cppast::parse_files_basic/).
+    type_safe::optional<libclang_compile_config> find_config_for(
+        const libclang_compilation_database& database, std::string file_name);
+
     /// A parser that uses libclang.
     class libclang_parser final : public parser
     {
     public:
+        using config = libclang_compile_config;
+
         explicit libclang_parser(type_safe::object_ref<const diagnostic_logger> logger);
         ~libclang_parser() noexcept override;
 
@@ -136,6 +160,29 @@ namespace cppast
         struct impl;
         std::unique_ptr<impl> pimpl_;
     };
+
+    /// Parses multiple files using a [cppast::libclang_parser]() and a compilation database.
+    ///
+    /// \effects Invokes [cppast::parse_files](standardese://parse_files_basic/) passing it the parser and file names,
+    /// and a `get_config` function using [cppast::find_config_for]().
+    ///
+    /// \throws [cppast::libclang_error]() if no configuration for a given file could be found in the database.
+    ///
+    /// \requires `FileParser` must use [cppast::libclang_parser](),
+    /// i.e. `FileParser::parser` must be an alias of [cppast::libclang_parser]().
+    template <class FileParser, class Range>
+    void parse_files(FileParser& parser, Range&& file_names,
+                     const libclang_compilation_database& database)
+    {
+        static_assert(std::is_same<typename FileParser::parser, libclang_parser>::value,
+                      "must use the libclang parser");
+        parse_files(parser, std::forward<Range>(file_names), [&](const std::string& file) {
+            auto config = find_config_for(database, file);
+            if (!config)
+                throw libclang_error("unable to find configuration for file '" + file + "'");
+            return config.value();
+        });
+    }
 } // namespace cppast
 
 #endif // CPPAST_LIBCLANG_PARSER_HPP_INCLUDED

include/cppast/parser.hpp

@@ -74,6 +74,9 @@ namespace cppast
     /// Base class for a parser.
     ///
     /// It reads a C++ source file and creates the matching [cppast::cpp_file]().
+    /// Derived classes can implement how the file is parsed.
+    ///
+    /// \requires A derived class must provide an alias `config` which is the corresponding derived class of the [cppast::compile_config]().
     class parser
     {
     public:
@@ -136,6 +139,104 @@ namespace cppast
         type_safe::object_ref<const diagnostic_logger> logger_;
         mutable std::atomic<bool>                      error_;
     };
+
+    /// A simple `FileParser` that parses all files synchronously.
+    ///
+    /// More advanced parsers could use a thread pool, for example.
+    template <class Parser>
+    class simple_file_parser
+    {
+        static_assert(std::is_base_of<cppast::parser, Parser>::value,
+                      "Parser must be derived from cppast::parser");
+
+    public:
+        using parser = Parser;
+        using config = typename Parser::config;
+
+        /// \effects Creates a file parser populating the given index
+        /// and using the parser created by forwarding the given arguments.
+        template <typename... Args>
+        explicit simple_file_parser(type_safe::object_ref<const cpp_entity_index> idx,
+                                    Args&&... args)
+        : parser_(std::forward<Args>(args)...), idx_(idx)
+        {
+        }
+
+        void parse(std::string path, const config& c)
+        {
+            auto file = parser_.parse(*idx_, std::move(path), c);
+            if (file)
+                files_.push_back(std::move(file));
+        }
+
+        /// \returns The result of [cppast::parser::error]().
+        bool error() const noexcept
+        {
+            return parser_.error();
+        }
+
+        /// \effects Calls [cppast::parser::reset_error]().
+        void reset_error() noexcept
+        {
+            parser_.reset_error();
+        }
+
+        /// \returns The index that is being populated.
+        const cpp_entity_index& index() const noexcept
+        {
+            return *idx_;
+        }
+
+        /// \returns An iteratable object iterating over all the files that have been parsed so far.
+        /// \exclude return
+        detail::iteratable_intrusive_list<cpp_file> files() const noexcept
+        {
+            return type_safe::ref(files_);
+        }
+
+    private:
+        Parser                                        parser_;
+        detail::intrusive_list<cpp_file>              files_;
+        type_safe::object_ref<const cpp_entity_index> idx_;
+    };
+
+    /// Parses multiple files using a given `FileParser`.
+    ///
+    /// \effects Will call the `parse()` function for each path specified in the `file_names`,
+    /// using `get_confg` to determine the configuration.
+    ///
+    /// \requires `FileParser` must be a class with the following members:
+    /// * `parser` - A typedef for the parser being used to do the parsing.
+    /// * `config` - The same as `parser::config`.
+    /// * `parse(path, config)` - Parses the given file with the configuration using its parser.
+    /// The parsing can be executed in a separated thread, but then a copy of the configuration and path must be created.
+    /// \requires `Range` must be some type that can be iterated in a range-based for loop.
+    /// \requires `Configuration` must be a function that returns a configuration of type `FileParser::config` when given a path.
+    /// \unique_name parse_files_basic
+    /// \synopsis_return void
+    template <class FileParser, class Range, class Configuration>
+    auto parse_files(FileParser& parser, Range&& file_names, const Configuration& get_config) ->
+        typename std::enable_if<std::is_same<typename std::decay<decltype(get_config(
+                                                 *std::forward<Range>(file_names).begin()))>::type,
+                                             typename FileParser::config>::value>::type
+    {
+        for (auto&& file : std::forward<Range>(file_names))
+        {
+            auto&& config = get_config(file);
+            parser.parse(std::forward<decltype(file)>(file),
+                         std::forward<decltype(config)>(config));
+        }
+    }
+
+    /// Parses multiple files using a given `FileParser` and configuration.
+    /// \effects Invokes [cppast::parse_files](standardese://parse_files_basic/) passing it the parser and file names,
+    /// and a function that returns the same configuration for each file.
+    template <class FileParser, class Range>
+    void parse_files(FileParser& parser, Range&& file_names, typename FileParser::config config)
+    {
+        parse_files(parser, std::forward<Range>(file_names),
+                    [&](const std::string&) { return config; });
+    }
 } // namespace cppast
 
 #endif // CPPAST_PARSER_HPP_INCLUDED

src/libclang/libclang_parser.cpp

@@ -51,6 +51,15 @@ libclang_compilation_database::~libclang_compilation_database()
         clang_CompilationDatabase_dispose(database_);
 }
 
+bool libclang_compilation_database::has_config(const char* file_name) const
+{
+    auto cxcommands = clang_CompilationDatabase_getCompileCommands(database_, file_name);
+    if (!cxcommands)
+        return false;
+    clang_CompileCommands_dispose(cxcommands);
+    return true;
+}
+
 namespace
 {
     int parse_number(const char*& str)
@@ -260,6 +269,30 @@ void libclang_compile_config::do_remove_macro_definition(std::string name)
     add_flag("-U" + std::move(name));
 }
 
+type_safe::optional<libclang_compile_config> cppast::find_config_for(
+    const libclang_compilation_database& database, std::string file_name)
+{
+    if (database.has_config(file_name))
+        return libclang_compile_config(database, std::move(file_name));
+
+    auto dot = file_name.rfind('.');
+    if (dot != std::string::npos)
+        file_name.erase(dot);
+
+    if (database.has_config(file_name))
+        return libclang_compile_config(database, std::move(file_name));
+    static const char* extensions[] = {".h",   ".hpp", ".cpp", ".h++", ".c++", ".hxx",
+                                       ".cxx", ".hh",  ".cc",  ".H",   ".C"};
+    for (auto ext : extensions)
+    {
+        auto name = file_name + ext;
+        if (database.has_config(name))
+            return libclang_compile_config(database, std::move(name));
+    }
+
+    return type_safe::nullopt;
+}
+
 struct libclang_parser::impl
 {
     detail::cxindex index;

test/CMakeLists.txt

@@ -28,6 +28,7 @@ set(tests
         cpp_variable.cpp
         integration.cpp
         libclang_parser.cpp
+        parser.cpp
         visitor.cpp)
 
 add_executable(cppast_test test.cpp test_parser.hpp ${tests})

test/parser.cpp

@@ -0,0 +1,71 @@
+// Copyright (C) 2017 Jonathan Müller <jonathanmueller.dev@gmail.com>
+// This file is subject to the license terms in the LICENSE file
+// found in the top-level directory of this distribution.
+
+#include <cppast/parser.hpp>
+
+#include <catch.hpp>
+
+using namespace cppast;
+
+TEST_CASE("parse_files")
+{
+    class null_compile_config : public compile_config
+    {
+    public:
+        null_compile_config() : compile_config({})
+        {
+        }
+
+    private:
+        void do_set_flags(cpp_standard, compile_flags) override
+        {
+        }
+
+        void do_add_include_dir(std::string) override
+        {
+        }
+
+        void do_add_macro_definition(std::string, std::string) override
+        {
+        }
+
+        void do_remove_macro_definition(std::string) override
+        {
+        }
+
+        const char* do_get_name() const noexcept override
+        {
+            return "null";
+        }
+    } config;
+
+    class null_parser : public parser
+    {
+    public:
+        using config = null_compile_config;
+
+        null_parser() : parser(type_safe::ref(logger_))
+        {
+        }
+
+    private:
+        std::unique_ptr<cpp_file> do_parse(const cpp_entity_index& idx, std::string path,
+                                           const compile_config&) const override
+        {
+            return cpp_file::builder(std::move(path)).finish(idx);
+        }
+
+        stderr_diagnostic_logger logger_;
+    };
+
+    cpp_entity_index                idx;
+    simple_file_parser<null_parser> parser(type_safe::ref(idx));
+
+    auto file_names = {"a.cpp", "b.cpp", "c.cpp"};
+    parse_files(parser, file_names, config);
+
+    auto iter = file_names.begin();
+    for (auto& file : parser.files())
+        REQUIRE(file.name() == *iter++);
+}