fix(parser): preserve quoted-key text in redefinition error messages

README.md

@@ -316,6 +316,7 @@ UTF-8 decoding is performed using a state machine based on Bjoern Hoehrmann's '[
 -   **[@rafal-c](https://github.com/rafal-c)** - Added a formatting flag
 -   **[@jfsimoneau](https://github.com/jfsimoneau)** - Fixed a meson option
 -   **[@ShereeMorphett](https://github.com/ShereeMorphett)** - Fixed reinterpret_cast usage
+-   **[@SAY-5](https://github.com/SAY-5)** - Fixed a parser bug
 <br>
 
 ## Contact

include/toml++/impl/parser.inl

@@ -1686,6 +1686,9 @@ TOML_IMPL_NAMESPACE_START
 			TOML_ASSERT_ASSUME(is_string_delimiter(*cp));
 			push_parse_scope("string"sv);
 
+			// snapshot length so the recording buffer can be rewound alongside go_back(2u) below
+			const auto recording_buffer_rollback_size = recording_buffer.length();
+
 			// get the first three characters to determine the string type
 			const auto first = cp->value;
 			advance_and_return_if_error_or_eof({});
@@ -1716,6 +1719,8 @@ TOML_IMPL_NAMESPACE_START
 				// step back two characters so that the current
 				// character is the string delimiter
 				go_back(2u);
+				if (recording)
+					recording_buffer.resize(recording_buffer_rollback_size);
 
 				return { first == U'\'' ? parse_literal_string(false) : parse_basic_string(false), false };
 			}

tests/parsing_tables.cpp

@@ -301,6 +301,34 @@ TEST_CASE("parsing - tables")
 						   });
 }
 
+TEST_CASE("parsing - redefinition error messages preserve quoted keys")
+{
+	// https://github.com/marzer/tomlplusplus/issues/300
+	static constexpr auto src = "[\"foo\"]\nx = 1\n[\"foo\"]\ny = 2\n"sv;
+#if TOML_EXCEPTIONS
+	std::string desc;
+	bool threw = false;
+	try
+	{
+		[[maybe_unused]] auto res = toml::parse(src);
+	}
+	catch (const toml::parse_error& err)
+	{
+		threw = true;
+		desc.assign(err.description());
+	}
+	REQUIRE(threw);
+	CHECK(desc.find("\"foo\"") != std::string::npos);
+	CHECK(desc.find("fofoo") == std::string::npos);
+#else
+	auto result = toml::parse(src);
+	REQUIRE(!result);
+	const std::string desc{ result.error().description() };
+	CHECK(desc.find("\"foo\"") != std::string::npos);
+	CHECK(desc.find("fofoo") == std::string::npos);
+#endif
+}
+
 TEST_CASE("parsing - inline tables")
 {
 	// these are the examples from https://toml.io/en/v1.0.0#inline-table

toml.hpp

@@ -14271,6 +14271,9 @@ TOML_IMPL_NAMESPACE_START
 			TOML_ASSERT_ASSUME(is_string_delimiter(*cp));
 			push_parse_scope("string"sv);
 
+			// snapshot length so the recording buffer can be rewound alongside go_back(2u) below
+			const auto recording_buffer_rollback_size = recording_buffer.length();
+
 			// get the first three characters to determine the string type
 			const auto first = cp->value;
 			advance_and_return_if_error_or_eof({});
@@ -14301,6 +14304,8 @@ TOML_IMPL_NAMESPACE_START
 				// step back two characters so that the current
 				// character is the string delimiter
 				go_back(2u);
+				if (recording)
+					recording_buffer.resize(recording_buffer_rollback_size);
 
 				return { first == U'\'' ? parse_literal_string(false) : parse_basic_string(false), false };
 			}