Added convert function and improved tests

Author: gregnr

README.md

@@ -55,28 +55,51 @@ yarn add ninprint
 ```
 
 ## Examples
+
+You can `print` directly to the console:
+
 ```javascript
-const { print: ninprint } = require("ninprint");
+const { print } = require("ninprint");
 
-ninprint("Hello world.");
+print("Hello world.");
 // Output:
 //     H e l l o [SPACE] w o r l d .
 
-ninprint("Line feed:\n");
+print("Line feed:\n");
 // Output:
 //     L i n e [SPACE] f e e d : [LF]
+```
+
+You can use `convert` to return a string:
 
-ninprint("Carriage return:\r");
+```javascript
+const { convert } = require("ninprint");
+
+const test1 = convert("Carriage return:\r");
+console.log(test1);
 // Output:
 //     C a r r i a g e [SPACE] r e t u r n : [CR]
 
-ninprint("Null character:\0");
+const test2 = convert("Null character:\0");
+console.log(test2);
 // Output:
 //     N u l l [SPACE] c h a r a c t e r : [NUL]
+```
 
-ninprint(new Buffer([0x00, 0x01, 0x02, 0x03, 0x04, 0x05]));
+You can also pass a `Buffer` to `print`/`convert`:
+
+```javascript
+
+const { print, convert } = require("ninprint");
+
+print(new Buffer([0x00, 0x01, 0x02, 0x03, 0x04, 0x05]));
 // Output:
 //     [NUL] [SOH] [STX] [ETX] [EOT] [ENQ]
+
+const test3 = convert(new Buffer([0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B]));
+console.log(test3);
+// Output:
+//     [ACK] [BEL] [BS] [TAB] [LF] [VT]
 ```
 
 # License

index.js

@@ -1,35 +1,39 @@
 const characterTable = require("./character-table.json");
 
-const print = (value, encoding = "ascii") => {
+const print = (value, encoding) => console.log(convert(value, encoding));
+
+const convert = (value, encoding = "ascii") => {
 
 	// Value is a String
 	if (typeof(value) === "string" || value instanceof String)
-		return printFromString(value);
+		return convertString(value);
 
 	// Value is a Buffer, first convert to String
 	else if (value instanceof Buffer)
-		return printFromString(value.toString(encoding));
+		return convertString(value.toString(encoding));
 
 	// Value has an unknown type
 	else
 		throw `Value passed must be a String or Buffer`;
-}
+};
 
-const printFromString = string => {
+const convertString = string => {
 
 	const symbols = [];
 
 	for (let i = 0; i < string.length; i++) {
 
 		const charCode = string.charCodeAt(i);
-		const symbol = characterTable[charCode].default;
+		const character = characterTable[charCode];
+		const symbol = character && character.default || string[i];
 
-		symbols.push(symbol || string[i]);
+		symbols.push(symbol);
 	}
 
-	console.log(symbols.join(" "));
+	return symbols.join(" ");
 };
 
 module.exports = {
-	print: print
+	print: print,
+	convert: convert
 };

test.js

@@ -1,7 +1,15 @@
-const { print: ninprint } = require("./");
+const { print: ninprint, convert } = require("./");
 
-ninprint("Hello world.");
-ninprint("Line feed:\n");
-ninprint("Carriage return:\r");
-ninprint("Null character:\0");
-ninprint(new Buffer([0x00, 0x01, 0x02, 0x03, 0x04, 0x05]));
+const assert = (condition, message) => {
+
+    if (!condition)
+		throw new Error(message || "Assertion failed");
+};
+
+assert(convert("Hello world.") === "H e l l o [SPACE] w o r l d .");
+assert(convert("Line feed:\n") === "L i n e [SPACE] f e e d : [LF]");
+assert(convert("Carriage return:\r") === "C a r r i a g e [SPACE] r e t u r n : [CR]");
+assert(convert("Null character:\0") === "N u l l [SPACE] c h a r a c t e r : [NUL]");
+assert(convert(new Buffer([0x00, 0x01, 0x02, 0x03, 0x04, 0x05])) === "[NUL] [SOH] [STX] [ETX] [EOT] [ENQ]");
+
+console.log("All tests passed");