Adding in a locale test to ensure we aren't dependent on the system locale settings when converting floats

See #8 for an example

Author: LinuxDevon

include/libdbc/utils/utils.hpp

@@ -42,6 +42,8 @@ class String {
 			cont.push_back(token);
 		}
 	}
+
+	static double convert_to_double(const std::string& value, double default_value = 0);
 };
 
 }

src/dbc.cpp

@@ -1,4 +1,3 @@
-#include <fast_float/fast_float.h>
 #include <libdbc/dbc.hpp>
 #include <libdbc/exceptions/error.hpp>
 #include <libdbc/utils/utils.hpp>
@@ -139,7 +138,6 @@ bool parseVal(const std::string& str, VALObject& obj) {
 	return false;
 }
 
-
 DbcParser::DbcParser()
 	: version("")
 	, nodes()
@@ -257,15 +255,12 @@ void DbcParser::parse_dbc_messages(const std::vector<std::string>& lines) {
 			uint32_t size = std::stoul(match.str(4));
 			bool is_bigendian = (std::stoul(match.str(5)) == 0);
 			bool is_signed = (match.str(6) == "-");
-			// Alternate groups because a group is for the decimal portion
-			double factor;
-			fast_float::from_chars(match.str(7).data(), match.str(7).data() + match.str(7).size(), factor);
-			double offset;
-			fast_float::from_chars(match.str(9).data(), match.str(9).data() + match.str(9).size(), offset);
-			double min;
-			fast_float::from_chars(match.str(11).data(), match.str(11).data() + match.str(11).size(), min);
-			double max;
-			fast_float::from_chars(match.str(13).data(), match.str(13).data() + match.str(13).size(), max);
+
+			double factor = utils::String::convert_to_double(match.str(7).data());
+			double offset = utils::String::convert_to_double(match.str(9).data());
+			double min = utils::String::convert_to_double(match.str(11).data());
+			double max = utils::String::convert_to_double(match.str(13).data());
+
 			std::string unit = match.str(15);
 
 			std::vector<std::string> receivers;

src/utils.cpp

@@ -1,3 +1,6 @@
+#include <charconv>
+#include <exception>
+#include <fast_float/fast_float.h>
 #include <libdbc/utils/utils.hpp>
 
 #include <regex>
@@ -69,4 +72,11 @@ std::string String::trim(const std::string& line) {
 	return start == end ? std::string() : line.substr(start, end - start + 1);
 }
 
+double String::convert_to_double(const std::string& value, double default_value) {
+	double converted_value = default_value;
+	fast_float::from_chars(value.data(), value.data() + value.size(), converted_value);
+	// converted_value = std::stod(value);
+	return converted_value;
+}
+
 } // Namespace Utils

test/CMakeLists.txt

@@ -22,3 +22,16 @@ target_link_libraries(dbcParserTests PRIVATE dbc Catch2::Catch2WithMain)
 target_include_directories(dbcParserTests PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
 
 catch_discover_tests(dbcParserTests)
+
+# We want a seperate binary for this test. We setup global locals which mess with all of the testing.
+# Opting for a sperate test running so we don't conflict
+add_executable(dbcLocaleTests
+    locale_testing/test_locale_main.cpp
+    common.cpp
+)
+
+target_compile_definitions(dbcLocaleTests PRIVATE TESTDBCFILES_PATH="${CMAKE_CURRENT_SOURCE_DIR}/dbcs")
+target_link_libraries(dbcLocaleTests PRIVATE dbc Catch2::Catch2WithMain)
+target_include_directories(dbcLocaleTests PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
+
+catch_discover_tests(dbcLocaleTests)

test/locale_testing/test_locale_main.cpp

@@ -0,0 +1,80 @@
+#include "common.hpp"
+#include "defines.hpp"
+#include <libdbc/dbc.hpp>
+#include <libdbc/utils/utils.hpp>
+
+#include <catch2/catch_approx.hpp>
+#include <catch2/catch_test_macros.hpp>
+#include <catch2/reporters/catch_reporter_event_listener.hpp>
+#include <catch2/reporters/catch_reporter_registrars.hpp>
+
+class testRunListener : public Catch::EventListenerBase {
+public:
+	using Catch::EventListenerBase::EventListenerBase;
+
+	void testRunStarting(Catch::TestRunInfo const&) override {
+		prev_loc = std::setlocale(LC_ALL, nullptr);
+		// Set the locale to something that has , instead of . for floats
+		std::locale::global(std::locale("de_DE.UTF-8"));
+	}
+
+	void testCaseEnded(Catch::TestCaseStats const&) override {
+		// Restore the old locale
+		std::locale::global(std::locale(prev_loc));
+	}
+
+private:
+	std::string prev_loc;
+};
+
+CATCH_REGISTER_LISTENER(testRunListener)
+
+TEST_CASE("Should parse doubld string locale independently") {
+	REQUIRE(Catch::Approx(utils::String::convert_to_double("6.82")) == 6.82);
+}
+
+TEST_CASE("Should process message with floats locale indpendently") {
+	const auto* filename = std::tmpnam(NULL);
+
+	create_tmp_dbc_with(filename, R"(BO_ 234 MSG1: 8 Vector__XXX
+ SG_ Sig1 : 55|16@0- (0.1,0) [-3276.8|-3276.7] "C" Vector__XXX
+ SG_ Sig2 : 39|16@0- (0.1,0) [-3276.8|-3276.7] "C" Vector__XXX
+ SG_ Sig3 : 23|16@0- (10,0) [-3276.8|-3276.7] "C" Vector__XXX
+ SG_ Sig4 : 7|16@0- (1,-10) [0|32767] "" Vector__XXX)");
+
+	auto parser = libdbc::DbcParser();
+	parser.parse_file(filename);
+
+	REQUIRE(parser.get_messages().size() == 1);
+	REQUIRE(parser.get_messages().at(0).name() == "MSG1");
+	REQUIRE(parser.get_messages().at(0).getSignals().size() == 4);
+
+	SECTION("Evaluating first message") {
+		const auto signal = parser.get_messages().at(0).getSignals().at(0);
+		REQUIRE(signal.factor == 0.1);
+		REQUIRE(signal.offset == 0);
+		REQUIRE(signal.min == -3276.8);
+		REQUIRE(signal.max == -3276.7);
+	}
+	SECTION("Evaluating second message") {
+		const auto signal = parser.get_messages().at(0).getSignals().at(1);
+		REQUIRE(signal.factor == 0.1);
+		REQUIRE(signal.offset == 0);
+		REQUIRE(signal.min == -3276.8);
+		REQUIRE(signal.max == -3276.7);
+	}
+	SECTION("Evaluating third message") {
+		const auto signal = parser.get_messages().at(0).getSignals().at(2);
+		REQUIRE(signal.factor == 10);
+		REQUIRE(signal.offset == 0);
+		REQUIRE(signal.min == -3276.8);
+		REQUIRE(signal.max == -3276.7);
+	}
+	SECTION("Evaluating fourth message") {
+		const auto signal = parser.get_messages().at(0).getSignals().at(3);
+		REQUIRE(signal.factor == 1);
+		REQUIRE(signal.offset == -10);
+		REQUIRE(signal.min == 0);
+		REQUIRE(signal.max == 32767);
+	}
+}