add %j as an alias for %O

.gitignore

@@ -0,0 +1 @@
+node_modules/

README.md

@@ -19,6 +19,7 @@ The placeholders in the format string are marked by "%" and are followed by one
     * e — print a float as scientific notation
     * u — print an integer as an unsigned decimal number
     * f — print a float as is
+    * j — print JSON of an object
     * o — print an integer as an octal number
     * O — print JSON of an object 
     * s — print a string as is

package.json

@@ -7,13 +7,16 @@
     "test": "test"
   },
   "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "test": "mocha"
   },
   "repository": {
     "type": "git",
     "url": "https://github.com/jontra/sprintf-fast.js"
   },
   "author": "Alexandru Marasteanu <hello@alexei.ro> (http://alexei.ro/)",
   "license": "BSD",
-  "readmeFilename": "README.md"
+  "readmeFilename": "README.md",
+  "devDependencies": {
+    "mocha": "^2.1.0"
+  }
 }

src/sprintf.js

@@ -31,7 +31,7 @@ sprintf.chr_repeat = function(chr, n){
     if (r && r.length>=n)
 	return r.slice(0, n);
     r = chr;
-    for (; r.length<n; r += r);
+    for (; r.length<n; r += r) {}
     chr_repeat_cache[chr] = r;
     return r.slice(0, n);
 };
@@ -47,7 +47,7 @@ sprintf.parse = function(fmt){
 	else if ((match = /^%%/.exec(_fmt)))
 	    f += 'out += "%";\n';
 	else if ((match =
-	    /^%(?:([1-9]\d*)\$|\(([^\)]+)\))?(\+)?(0|'[^$])?(-)?(\d+)?(?:\.(\d+))?([bcdefoOsuxX])/
+	    /^%(?:([1-9]\d*)\$|\(([^\)]+)\))?(\+)?(0|'[^$])?(-)?(\d+)?(?:\.(\d+))?([bcdefjoOsuxX])/
 	    .exec(_fmt)))
 	{
 	    var positional = match[1], keyword = match[2], sign = match[3];
@@ -88,7 +88,7 @@ sprintf.parse = function(fmt){
 		f += 'arg = argv['+positional+'];\n';
 	    else /* positional argument (implicit) */
 		f += 'arg = argv['+(cursor++)+'];\n';
-	    if (/[^sO]/.test(conversion))
+	    if (/[^jsO]/.test(conversion))
 		f += 'arg = +arg;\n';
 	    switch (conversion)
 	    {
@@ -107,8 +107,10 @@ sprintf.parse = function(fmt){
 		else
                     f += 'arg_s = ""+arg;\n';
 		break;
+	    case 'j':
+	    case 'O':
+		f += 'arg_s = JSON.stringify(arg);\n'; break;
 	    case 'o': f += 'arg_s = arg.toString(8);\n'; break;
-	    case 'O': f += 'arg_s = JSON.stringify(arg);\n'; break;
             case 'u': f += 'arg = arg >>> 0; arg_s = ""+arg;\n'; break;
 	    case 'x': f += 'arg_s = arg.toString(16);\n'; break;
 	    case 'X': f += 'arg_s = arg.toString(16).toUpperCase();\n'; break;

test/test.js

@@ -30,6 +30,9 @@ describe('sprintf', function(){
         t('%O', [1], '1');
         t('%O', ["1"], '"1"');
         t('%O', [{a: 1, b: 2}], '{"a":1,"b":2}');
+        t('%j', [1], '1');
+        t('%j', ["1"], '"1"');
+        t('%j', [{a: 1, b: 2}], '{"a":1,"b":2}');
         t('%(aa)s', [{aa: "AA"}], 'AA');
         t('%(aa[1])s', [{aa: [1, 2]}], '2');
         t('%(aa[1].b.c[0][1])s', [{aa: [0, {b: {c: [[4, 5]]}}]}], '5');