[Yul] Format string literals back to quoted string literals

libdevcore/CommonData.cpp

@@ -23,6 +23,7 @@
 #include <libdevcore/Exceptions.h>
 #include <libdevcore/Assertions.h>
 #include <libdevcore/Keccak256.h>
+#include <libdevcore/FixedHash.h>
 
 #include <boost/algorithm/string.hpp>
 
@@ -181,3 +182,15 @@ bool dev::isValidDecimal(string const& _string)
 		return false;
 	return true;
 }
+
+// Returns a quoted string if all characters are printable ASCII chars,
+// or its hex representation otherwise.
+std::string dev::formatAsStringOrNumber(std::string const& _value)
+{
+	if (_value.length() <= 32)
+		for (auto const& c: _value)
+			if (c <= 0x1f || c >= 0x7f || c == '"')
+				return "0x" + h256(_value, h256::AlignLeft).hex();
+
+	return "\"" + _value + "\"";
+}

libdevcore/CommonData.h

@@ -290,7 +290,6 @@ void iterateReplacing(std::vector<T>& _vector, F const& _f)
 		_vector = std::move(modifiedVector);
 }
 
-
 namespace detail
 {
 template <typename T, typename F, std::size_t... I>
@@ -355,6 +354,10 @@ std::string getChecksummedAddress(std::string const& _addr);
 bool isValidHex(std::string const& _string);
 bool isValidDecimal(std::string const& _string);
 
+/// @returns a quoted string if all characters are printable ASCII chars,
+/// or its hex representation otherwise.
+std::string formatAsStringOrNumber(std::string const& _value);
+
 template<typename Container, typename Compare>
 bool containerEqual(Container const& _lhs, Container const& _rhs, Compare&& _compare)
 {