Allow for quoted empty strings with double-quotes (fixes #16)

README.md

@@ -27,7 +27,7 @@ var output = postcss()
   .css;
 ```
 
-Using this ```input.css```: 
+Using this ```input.css```:
 
 ```css
 .foo {
@@ -70,7 +70,7 @@ and with [postcss-for]:
 
 ```css
 @for $i from 1 to 3 {
-  .b-$i { 
+  .b-$i {
     width: $i px;
     @if $i == 2 {
       color: green;
@@ -79,4 +79,9 @@ and with [postcss-for]:
 }
 ```
 
-[postcss-for]: https://github.com/antyakushev/postcss-for
+[postcss-for]: https://github.com/antyakushev/postcss-for
+
+## Development
+1. Clone repository
+2. Install dependencies `npm install`
+3. If `parser.jison` file has been changed, regenerate `parser.js` by running `npm run gen-parser`

package.json

@@ -25,10 +25,12 @@
     "postcss": "^5.0.4"
   },
   "devDependencies": {
+    "jison": "^0.4.17",
     "tap-dot": "^1.0.0",
     "tape": "^4.0.2"
   },
   "scripts": {
-    "test": "node test/test.js | tap-dot"
+    "test": "node test/test.js | tap-dot",
+    "gen-parser": "jison parser.jison"
   }
 }

parser.jison

@@ -201,6 +201,7 @@ hsla\(\s*[0-9]+\s*\,\s*[0-9]+\%\s*\,\s*[0-9]+\%\s*\,\s*([0-1]|0?\.[0-9]+)\s*\)
 [0-9]+("."[0-9]+)?\b                                                                  return 'NUMBER';
 [a-zA-Z0-9-_.]+\b                                                                     return 'STRING';
 \'(\\[^\']|[^\'\\])*\'                                                                yytext = yytext.slice(1,-1); return 'STRING';
+\"(\\[^\"]|[^\"\\])*\"                                                                yytext = yytext.slice(1,-1); return 'STRING';
 "("                                                                                   return 'LPAREN';
 ")"                                                                                   return 'RPAREN';
 "=="                                                                                  return 'RELOP';

test/test.js

@@ -85,6 +85,9 @@ test('@if true { foo: bar } @else if false { bar: baz } @else { bat: quux }', 'f
 test('@if false { foo: bar } @else if true { bar: baz } @else { bat: quux }', 'bar: baz');
 test('@if false { foo: bar } @else if false { bar: baz } @else { bat: quux }', 'bat: quux');
 test('@if \'\' == \'\' { foo: bar }', 'foo: bar');
+test('@if "" == "" { foo: bar }', 'foo: bar');
+test('@if \'\' == "" { foo: bar }', 'foo: bar');
+test('@if "" == \'\' { foo: bar }', 'foo: bar');
 test('@if \'foo\\bar\' == \'foo\\bar\' { foo: bar }', 'foo: bar');
 test('@if .foo == .foo { foo: bar }', 'foo: bar');
 test('@if .foo == .bar { foo: bar }', '');