Add 'tomlplusplus/' from commit '1c8b7466e4946fcc3bf20484c0e1d001202cca5a'

git-subtree-dir: tomlplusplus
git-subtree-mainline: b85e90fc3480da0e6a48da73201a0b22488cc650
git-subtree-split: 1c8b7466e4946fcc3bf20484c0e1d001202cca5a

1 files changed, 210 insertions, 0 deletions

diff --git a/tomlplusplus/examples/error_printer.cpp b/tomlplusplus/examples/error_printer.cpp
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+++ b/tomlplusplus/examples/error_printer.cpp
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+// This file is a part of toml++ and is subject to the the terms of the MIT license.
+// Copyright (c) Mark Gillard <mark.gillard@outlook.com.au>
+// See https://github.com/marzer/tomlplusplus/blob/master/LICENSE for the full license text.
+// SPDX-License-Identifier: MIT
+
+// This example shows the error messages the library produces by forcing a set of specific parsing
+// failures and printing their results.
+
+#include "examples.hpp"
+#include <toml++/toml.hpp>
+#include <cctype>  // For iscntrl.
+#include <iomanip> // For setfill, hex, etc.
+#include <optional>
+
+using namespace std::string_view_literals;
+
+namespace
+{
+	inline constexpr auto invalid_parses = std::array{
+		"########## comments and whitespace"sv,
+		"# bar\rkek"sv,
+		"# bar\bkek"sv,
+		"# DEL character: '\x7f'"sv,
+		"# \xf1\x63"sv,
+		"# val1 = 1\fval2 = 2"sv,
+		"foo = 1\n\u2000\nbar = 2"sv,
+
+		"########## inline tables"sv,
+		"val = {,}"sv,
+		"val = {a='b',}"sv, // allowed when TOML_ENABLE_UNRELEASED_FEATURES == 1
+		"val = {a='b',,}"sv,
+		"val = {a='b',"sv,
+		"val = {a='b',\n c='d'}"sv, // allowed when TOML_ENABLE_UNRELEASED_FEATURES == 1
+		"val = {?='b'}"sv,
+		"foo = {} \n [foo.bar]"sv,
+
+		"########## tables"sv,
+		"[]"sv,
+		"[foo"sv,
+		"[foo] ?"sv,
+		"[foo] [bar]"sv,
+		"[foo]\n[foo]"sv,
+		"? = 'foo' ?"sv,
+		"[ [foo] ]"sv,
+
+		"########## arrays"sv,
+		"val = [,]"sv,
+		"val = ['a',,]"sv,
+		"val = ['a',"sv,
+
+		"########## key-value pairs"sv,
+		"val = 'foo' ?"sv,
+		"val = "sv,
+		"val "sv,
+		"val ?"sv,
+		"val = ]"sv,
+		"[foo]\nbar = 'kek'\nbar = 'kek2'"sv,
+		"[foo]\nbar = 'kek'\nbar = 7"sv,
+		"[foo.bar]\n[foo]\nbar = 'kek'"sv,
+		"[foo]\nbar = 'kek'\nbar.kek = 7"sv,
+		"[foo]\nbar.? = 'kek'"sv,
+		R"('''val''' = 1)"sv,
+		R"(a."""val""" = 1)"sv,
+		"1= 0x6cA#+\xf1"sv,
+		R"(😂 = 3)"sv, // allowed when TOML_ENABLE_UNRELEASED_FEATURES == 1
+
+		"########## values"sv,
+		"val = _"sv,
+		"val = G"sv,
+		"PATHOLOGICALLY_NESTED"sv, // generated inline
+
+		"########## strings"sv,
+		"val = \" \r \""sv,
+		R"(val = ")"sv,
+		R"(val = "\g")"sv,
+		R"(val = "\x20")"sv, // allowed when TOML_ENABLE_UNRELEASED_FEATURES == 1
+		R"(val = "\uFFF")"sv,
+		R"(val = "\uFFFG")"sv,
+		R"(val = "\UFFFFFFF")"sv,
+		R"(val = "\UFFFFFGF")"sv,
+		R"(val = "\uD801")"sv,
+		R"(val = "\U00110000")"sv,
+		R"(val = """ """""")"sv,
+		R"(val = ''' '''''')"sv,
+		"val = '\n'"sv,
+
+		"########## integers"sv,
+		R"(val = -0b0)"sv,
+		R"(val = -0o0)"sv,
+		R"(val = -0x0)"sv,
+		R"(val = +0b0)"sv,
+		R"(val = +0o0)"sv,
+		R"(val = +0x0)"sv,
+		R"(val = 1-)"sv,
+		R"(val = -1+)"sv,
+		R"(val = -+1)"sv,
+		R"(val = 1_0_)"sv,
+		R"(val = 1_0_ )"sv,
+		R"(val = 01 )"sv,
+		R"(val = 0b10000000_00000000_00000000_00000000_00000000_00000000_00000000_00000000 )"sv,
+		R"(val = 0o1000000000000000000000 )"sv,
+		R"(val = 9223372036854775808 )"sv,
+		R"(val = 0x8000000000000000 )"sv,
+
+		"########## floats"sv,
+		R"(val = 100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000.0)"sv,
+	};
+
+	inline constexpr auto divider =
+		"################################################################################"sv;
+
+	void print_string(std::string_view str)
+	{
+		for (char c : str)
+		{
+			if (std::optional<std::string_view> escape_sequence = (c == '\\') ? "\\\\"sv
+																: (c == '\a') ? "\\a"sv
+																: (c == '\b') ? "\\b"sv
+																: (c == '\f') ? "\\f"sv
+																: (c == '\n') ? "\\n"sv
+																: (c == '\r') ? "\\r"sv
+																: (c == '\t') ? "\\t"sv
+																: (c == '\v') ? "\\v"sv
+																			  : std::optional<std::string_view>{})
+			{
+				std::cout << *escape_sequence;
+			}
+			else
+			{
+				if (c >= 0 && std::iscntrl(c))
+				{
+					// Print a string, just like `toml::impl::control_char_escapes[c]`.
+					std::ostringstream stream;
+					stream << "\\u00"sv << std::setfill('0') << std::setw(2) << std::hex << std::uppercase << int{ c };
+					std::cout << stream.str();
+				}
+				else
+				{
+					std::cout << c;
+				}
+			}
+		}
+	}
+
+	void print_parse_error(std::string_view doc, const toml::parse_error& err)
+	{
+		std::cout << err;
+
+		auto line_num = err.source().begin.line;
+
+		if (auto line = toml::get_line(doc, line_num))
+		{
+			std::cout << "\nLine "sv << line_num << ": "sv;
+			print_string(*line);
+		}
+		std::cout << "\n\n"sv;
+	}
+}
+
+int main()
+{
+	const auto parse_and_print_if_error = [](std::string_view str)
+	{
+#if TOML_EXCEPTIONS
+		try
+		{
+			auto result = toml::parse(str);
+			static_cast<void>(result);
+		}
+		catch (const toml::parse_error& err)
+		{
+			print_parse_error(str, err);
+		}
+#else
+		if (auto result = toml::parse(str); !result)
+			print_parse_error(str, result.error());
+#endif
+	};
+
+	for (auto str : invalid_parses)
+	{
+		if (str.empty())
+			continue;
+
+		// section headings
+		if (str.substr(0, 10) == "##########"sv)
+		{
+			std::cout << divider << '\n';
+			std::cout << "#    "sv << str.substr(11) << '\n';
+			std::cout << divider << "\n\n"sv;
+		}
+
+		// error messages
+		else
+		{
+			toml::parse_result result;
+
+			if (str == "PATHOLOGICALLY_NESTED"sv)
+			{
+				std::string s(1000u, '[');
+				constexpr auto start = "array = "sv;
+				memcpy(s.data(), start.data(), start.length());
+				parse_and_print_if_error(s);
+			}
+			else
+				parse_and_print_if_error(str);
+		}
+	}
+	return 0;
+}