Revise ArrayPrinter to escape character data, remove separator parameter

Author: mikee47

src/include/FlashString/Array.hpp

@@ -119,9 +119,9 @@ template <typename ElementType> class Array : public Object<Array<ElementType>,
 	 * @brief Returns a printer object for this array
 	 * @note ElementType must be supported by Print
 	 */
-	ArrayPrinter<Array> printer(const WString& separator = ", ") const
+	ArrayPrinter<Array> printer() const
 	{
-		return ArrayPrinter<Array>(*this, separator);
+		return ArrayPrinter<Array>(*this);
 	}
 
 	size_t printTo(Print& p) const

src/include/FlashString/ArrayPrinter.hpp

@@ -20,39 +20,96 @@
 #pragma once
 
 #include "Print.hpp"
+#include <stringutil.h>
 
 namespace FSTR
 {
+template <typename T> typename std::enable_if<!std::is_same<T, char>::value, size_t>::type printElement(Print& p, T e)
+{
+	return print(p, e);
+}
+
+template <typename T> typename std::enable_if<std::is_same<T, char>::value, size_t>::type printElement(Print& p, T c)
+{
+	auto escape = [](char c) -> char {
+		switch(c) {
+		case '\0':
+			return '0';
+		case '\'':
+			return '\'';
+		case '\"':
+			return '"';
+		case '\?':
+			return '?';
+		case '\\':
+			return '\\';
+		case '\a':
+			return 'a';
+		case '\b':
+			return 'b';
+		case '\f':
+			return 'f';
+		case '\n':
+			return 'n';
+		case '\r':
+			return 'r';
+		case '\t':
+			return 't';
+		case '\v':
+			return 'v';
+		default:
+			return '\0';
+		}
+	};
+
+	char buf[8];
+	char* o = buf;
+	*o++ = '\'';
+	char esc = escape(c);
+	if(esc) {
+		*o++ = '\\';
+		*o++ = esc;
+	} else if(isprint(c)) {
+		*o++ = c;
+	} else {
+		*o++ = '\\';
+		*o++ = 'x';
+		*o++ = hexchar(uint8_t(c) >> 4);
+		*o++ = hexchar(uint8_t(c) & 0x0f);
+	}
+	*o++ = '\'';
+	return p.write(buf, o - buf);
+}
+
 /**
  * @brief Class template to provide a simple way to print the contents of an array
  * @note Used by Array::printTo() method
  */
 template <class ArrayType> class ArrayPrinter : public Printable
 {
 public:
-	ArrayPrinter(const ArrayType& array, const WString& separator) : array(array), separator(separator)
+	ArrayPrinter(const ArrayType& array) : array(array)
 	{
 	}
 
 	size_t printTo(Print& p) const override
 	{
 		size_t count = 0;
 
-		count += p.print("[");
+		count += p.print('{');
 		for(unsigned i = 0; i < array.length(); ++i) {
 			if(i > 0) {
-				count += p.print(separator);
+				count += p.print(", ");
 			}
-			count += print(p, array[i]);
+			count += printElement(p, array[i]);
 		}
-		count += p.print("]");
+		count += p.print('}');
 
 		return count;
 	}
 
 private:
 	const ArrayType& array;
-	WString separator;
 };
 
 } // namespace FSTR

src/include/FlashString/Table.hpp

@@ -66,7 +66,7 @@ template <typename ElementType, size_t Columns> class TableRow
 	 */
 	size_t printTo(Print& p) const
 	{
-		return FSTR::ArrayPrinter<TableRow>(*this, ", ").printTo(p);
+		return FSTR::ArrayPrinter<TableRow>(*this).printTo(p);
 	}
 
 	/**

src/include/FlashString/Vector.hpp

@@ -146,9 +146,9 @@ template <class ObjectType> class Vector : public Object<Vector<ObjectType>, Obj
 
 	/* Arduino Print support */
 
-	ArrayPrinter<Vector> printer(const WString& separator = ", ") const
+	ArrayPrinter<Vector> printer() const
 	{
-		return ArrayPrinter<Vector>(*this, separator);
+		return ArrayPrinter<Vector>(*this);
 	}
 
 	size_t printTo(Print& p) const