Double always with decimal

include/yaramod/utils/utils.h

@@ -9,6 +9,7 @@
 #include <cctype>
 #include <sstream>
 #include <string>
+#include <cmath>
 
 namespace yaramod {
 
@@ -48,12 +49,44 @@ template <typename T>
 std::string numToStr(const T num, std::ios_base &(*format)(std::ios_base&) = std::dec, bool showbase = false, bool toUpper = false)
 {
 	std::ostringstream os;
+
+	// Set precision if num is floating point
+	if (std::is_floating_point<T>::value)
+		os.precision(std::numeric_limits<T>::digits10 - 1);
+
+	os << std::fixed;
 	if (toUpper)
 		os << std::uppercase;
 	if (showbase)
 		os << format << std::showbase << num;
 	else
 		os << format << num;
+
+	// Postprocess value if value is floating point
+	if (std::is_floating_point<T>::value)
+	{
+		std::string value = os.str();
+		auto comma = value.find('.');
+
+		// Generated string presentation do not have comma add .0 (xxxx)
+		if (comma == std::string::npos)
+		{
+			return value.append(".0");
+		}
+		// Generated string presentation have comma on last place (xxxx.)
+		if (comma == value.length() - 1)
+		{
+			return value.append("0");
+		}
+		// Generated string have format xxx.x
+		if (comma == value.length() - 2)
+		{
+			return value;
+		}
+		// Trim tailing zeros from generated float presentation (10.030000000 -> 10.03)
+		auto zero = value.find_last_not_of('0');
+		return {value.begin(), value.begin() + static_cast<long>(std::max(zero + 1, comma + 2))};
+	}
 	return os.str();
 }
 

tests/cpp/builder_tests.cpp

@@ -1927,5 +1927,35 @@ auto cond = boolVal(false).defined().get();
 )", yaraFile->getTextFormatted());
 }
 
+
+TEST_F(BuilderTests,
+FloatValueWorks) {
+	auto cond = doubleVal(0.0).get();
+
+	YaraRuleBuilder newRule;
+	auto rule = newRule
+		.withName("float_value_works")
+		.withCondition(cond)
+		.get();
+
+	YaraFileBuilder newFile;
+	auto yaraFile = newFile
+		.withRule(std::move(rule))
+		.get(true);
+
+	ASSERT_NE(nullptr, yaraFile);
+	EXPECT_EQ(R"(rule float_value_works {
+	condition:
+		0.0
+})", yaraFile->getText());
+
+	EXPECT_EQ(R"(rule float_value_works
+{
+	condition:
+		0.0
+}
+)", yaraFile->getTextFormatted());
+}
+
 }
 }

tests/cpp/parser_tests.cpp

@@ -3264,6 +3264,46 @@ rule same_variable_in_nested_for_loops
 	}
 }
 
+TEST_F(ParserTests,
+FloatValueWorks) {
+	prepareInput(
+R"(
+rule rule_with_float_value_in_condition
+{
+	condition:
+		0.8699322552472 == 0.8699322552472
+}
+)");
+
+	EXPECT_TRUE(driver.parse(input));
+	ASSERT_EQ(1u, driver.getParsedFile().getRules().size());
+
+	const auto& rule = driver.getParsedFile().getRules()[0];
+	EXPECT_EQ(R"(0.8699322552472 == 0.8699322552472)", rule->getCondition()->getText());
+
+	EXPECT_EQ(input_text, driver.getParsedFile().getTextFormatted());
+}
+
+TEST_F(ParserTests,
+FloatValueWorks2) {
+	prepareInput(
+R"(
+rule rule_with_float_value_in_condition
+{
+	condition:
+		0.0000000001 == 0.0000000001
+}
+)");
+
+	EXPECT_TRUE(driver.parse(input));
+	ASSERT_EQ(1u, driver.getParsedFile().getRules().size());
+
+	const auto& rule = driver.getParsedFile().getRules()[0];
+	EXPECT_EQ(R"(0.0000000001 == 0.0000000001)", rule->getCondition()->getText());
+
+	EXPECT_EQ(input_text, driver.getParsedFile().getTextFormatted());
+}
+
 TEST_F(ParserTests,
 CuckooModuleWorks) {
 	prepareInput(

tests/cpp/utils_tests.cpp

@@ -58,5 +58,16 @@ UnescapeStringWorks) {
 	EXPECT_EQ("\n\t\\\"\x01", unescapeString(R"(\n\t\\\"\x01)"));
 }
 
+TEST_F(UtilsTests,
+NumToStrWorks) {
+	EXPECT_EQ("10", numToStr<int>(10));
+	EXPECT_EQ("a", numToStr<int>(10, std::hex));
+	EXPECT_EQ("10.0", numToStr<double>(10.0));
+	EXPECT_EQ("10.05", numToStr<double>(10.05));
+	EXPECT_EQ("0.0000000001", numToStr<double>(0.0000000001));
+	EXPECT_EQ("0.0", numToStr<double>(0.0));
+	EXPECT_EQ("0.869932552472", numToStr<double>(0.869932552472));
+}
+
 }
 }