Added single character emitting

include/yaml-cpp/emitter.h

@@ -51,6 +51,7 @@ namespace YAML
 		// overloads of write
 		Emitter& Write(const std::string& str);
 		Emitter& Write(bool b);
+		Emitter& Write(char ch);
 		Emitter& Write(const _Alias& alias);
 		Emitter& Write(const _Anchor& anchor);
 		Emitter& Write(const _Tag& tag);
@@ -125,6 +126,7 @@ namespace YAML
 	// overloads of insertion
 	inline Emitter& operator << (Emitter& emitter, const std::string& v) { return emitter.Write(v); }
 	inline Emitter& operator << (Emitter& emitter, bool v) { return emitter.Write(v); }
+	inline Emitter& operator << (Emitter& emitter, char v) { return emitter.Write(v); }
 	inline Emitter& operator << (Emitter& emitter, const _Alias& v) { return emitter.Write(v); }
 	inline Emitter& operator << (Emitter& emitter, const _Anchor& v) { return emitter.Write(v); }
 	inline Emitter& operator << (Emitter& emitter, const _Tag& v) { return emitter.Write(v); }

src/emitter.cpp

@@ -733,6 +733,20 @@ namespace YAML
 		return *this;
 	}
 
+	Emitter& Emitter::Write(char ch)
+	{
+		if(!good())
+			return *this;
+		
+		PreAtomicWrite();
+		EmitSeparationIfNecessary();
+		
+		Utils::WriteChar(m_stream, ch);
+		
+		PostAtomicWrite();
+		return *this;
+	}
+
 	Emitter& Emitter::Write(const _Alias& alias)
 	{
 		if(!good())

src/emitterutils.cpp

@@ -268,6 +268,26 @@ namespace YAML
 			return true;
 		}
 		
+		bool WriteChar(ostream& out, char ch)
+		{
+			if(('a' <= ch && ch <= 'z') || ('A' <= ch && ch <= 'Z'))
+				out << ch;
+			else if((0x20 <= ch && ch <= 0x7e) || ch == ' ')
+				out << "\"" << ch << "\"";
+			else if(ch == '\t')
+				out << "\"\\t\"";
+			else if(ch == '\n')
+				out << "\"\\n\"";
+			else if(ch == '\b')
+				out << "\"\\b\"";
+			else {
+				out << "\"";
+				WriteDoubleQuoteEscapeSequence(out, ch);
+				out << "\"";
+			}
+			return true;
+		}
+
 		bool WriteComment(ostream& out, const std::string& str, int postCommentIndent)
 		{
 			const unsigned curIndent = out.col();

src/emitterutils.h

@@ -17,6 +17,7 @@ namespace YAML
 		bool WriteSingleQuotedString(ostream& out, const std::string& str);
 		bool WriteDoubleQuotedString(ostream& out, const std::string& str, bool escapeNonAscii);
 		bool WriteLiteralString(ostream& out, const std::string& str, int indent);
+		bool WriteChar(ostream& out, char ch);
 		bool WriteComment(ostream& out, const std::string& str, int postCommentIndent);
 		bool WriteAlias(ostream& out, const std::string& str);
 		bool WriteAnchor(ostream& out, const std::string& str);

test/emittertests.cpp

@@ -861,8 +861,21 @@ namespace Test
 			out << YAML::EndMap;
 			desiredOutput = "key: \"\"";
 		}
+		
+		void SingleChar(YAML::Emitter& out, std::string& desiredOutput)
+		{
+			out << YAML::BeginSeq;
+			out << 'a';
+			out << ':';
+			out << (char)0x10;
+			out << '\n';
+			out << ' ';
+			out << '\t';
+			out << YAML::EndSeq;
+			desiredOutput = "- a\n- \":\"\n- \"\\x10\"\n- \"\\n\"\n- \" \"\n- \"\\t\"";
+		}
 
-		////////////////////////////////////////////////////////////////////////////////////////////////////////
+	////////////////////////////////////////////////////////////////////////////////////////////////////////
 		// incorrect emitting
 		
 		void ExtraEndSeq(YAML::Emitter& out, std::string& desiredError)
@@ -1080,6 +1093,7 @@ namespace Test
 		RunEmitterTest(&Emitter::DocStartAndEnd, "doc start and end", passed, total);
 		RunEmitterTest(&Emitter::ImplicitDocStart, "implicit doc start", passed, total);
 		RunEmitterTest(&Emitter::EmptyString, "empty string", passed, total);
+		RunEmitterTest(&Emitter::SingleChar, "single char", passed, total);
 		
 		RunEmitterErrorTest(&Emitter::ExtraEndSeq, "extra EndSeq", passed, total);
 		RunEmitterErrorTest(&Emitter::ExtraEndMap, "extra EndMap", passed, total);