diff --git a/include/chaiscript/language/chaiscript_engine.hpp b/include/chaiscript/language/chaiscript_engine.hpp index 4afd0449..a88b9d70 100644 --- a/include/chaiscript/language/chaiscript_engine.hpp +++ b/include/chaiscript/language/chaiscript_engine.hpp @@ -80,6 +80,7 @@ namespace chaiscript { std::map> m_namespace_generators; std::function m_print_handler = [](const std::string &) noexcept {}; + std::function m_file_reader; /// Evaluates the given string in by parsing it and running the results through the evaluator Boxed_Value do_eval(const std::string &t_input, const std::string &t_filename = "__EVAL__", bool /* t_internal*/ = false) { @@ -139,6 +140,10 @@ namespace chaiscript { m_print_handler = t_handler; }), "set_print_handler"); + m_engine.add(fun([this](const std::function &t_reader) { + m_file_reader = t_reader; + }), "set_file_reader"); + m_engine.add(fun([this]() { m_engine.dump_system(); }), "dump_system"); m_engine.add(fun([this](const Boxed_Value &t_bv) { m_engine.dump_object(t_bv); }), "dump_object"); m_engine.add(fun([this](const Boxed_Value &t_bv, const std::string &t_type) { return m_engine.is_type(t_bv, t_type); }), "is_type"); @@ -236,7 +241,15 @@ namespace chaiscript { } /// Helper function for loading a file - static std::string load_file(const std::string &t_filename) { + std::string load_file(const std::string &t_filename) const { + if (m_file_reader) { + return m_file_reader(t_filename); + } + + return load_file_default(t_filename); + } + + static std::string load_file_default(const std::string &t_filename) { std::ifstream infile(t_filename.c_str(), std::ios::in | std::ios::ate | std::ios::binary); if (!infile.is_open()) { @@ -278,6 +291,12 @@ namespace chaiscript { m_print_handler = std::move(t_handler); } + /// \brief Set a custom handler for reading files, used by eval_file, use, and internal_eval_file + /// \param[in] t_reader Function to call with the filename, returning the file contents as a string + void set_file_reader(std::function t_reader) { + m_file_reader = std::move(t_reader); + } + /// \brief Virtual destructor for ChaiScript virtual ~ChaiScript_Basic() = default; diff --git a/unittests/compiled_tests.cpp b/unittests/compiled_tests.cpp index 7b601b15..8d342d61 100644 --- a/unittests/compiled_tests.cpp +++ b/unittests/compiled_tests.cpp @@ -1782,3 +1782,42 @@ TEST_CASE("eval_error with AST_Node_Trace call stack compiles in C++20") { (void)stack; } } + +TEST_CASE("Test set_file_reader from C++ land") { + chaiscript::ChaiScript chai; + chai.set_file_reader([](const std::string &) { + return std::string("var file_reader_test_val = 42"); + }); + chai.eval_file("nonexistent_file.chai"); + CHECK(chai.eval("file_reader_test_val") == 42); +} + +TEST_CASE("Test set_file_reader from ChaiScript land") { + chaiscript::ChaiScript chai; + chai.set_file_reader([](const std::string &) { + return std::string("var from_custom_reader = true"); + }); + chai.eval("set_file_reader(fun(filename) { return \"var from_chai_reader = true\"; })"); + chai.eval_file("any_file.chai"); + CHECK(chai.eval("from_chai_reader") == true); +} + +TEST_CASE("Test set_file_reader receives correct filename") { + chaiscript::ChaiScript chai; + std::string captured_filename; + chai.set_file_reader([&captured_filename](const std::string &t_filename) { + captured_filename = t_filename; + return std::string("var dummy = 1"); + }); + chai.eval_file("my_special_file.chai"); + CHECK(captured_filename == "my_special_file.chai"); +} + +TEST_CASE("Test use with set_file_reader") { + chaiscript::ChaiScript chai; + chai.set_file_reader([](const std::string &) { + return std::string("var use_reader_val = 99"); + }); + chai.use("virtual_file.chai"); + CHECK(chai.eval("use_reader_val") == 99); +}