Add support for utf8 name in input source map encoding

Author: ai

lib/previous-map.es6

@@ -37,9 +37,10 @@ export default class PreviousMap {
     }
 
     decodeInline(text) {
-        let utf64 = 'data:application/json;charset=utf-8;base64,';
-        let b64   = 'data:application/json;base64,';
-        let uri   = 'data:application/json,';
+        let utfd64 = 'data:application/json;charset=utf-8;base64,';
+        let utf64  = 'data:application/json;charset=utf8;base64,';
+        let b64    = 'data:application/json;base64,';
+        let uri    = 'data:application/json,';
 
         if ( this.startWith(text, uri) ) {
             return decodeURIComponent( text.substr(uri.length) );
@@ -50,6 +51,9 @@ export default class PreviousMap {
         } else if ( this.startWith(text, utf64) ) {
             return Base64.decode( text.substr(utf64.length) );
 
+        } else if ( this.startWith(text, utfd64) ) {
+            return Base64.decode( text.substr(utfd64.length) );
+
         } else {
             let encoding = text.match(/data:application\/json;([^,]+),/)[1];
             throw new Error('Unsupported source map encoding ' + encoding);

test/previous-map.es6

@@ -76,6 +76,14 @@ describe('PreviousMap', () => {
         expect(parse(css).source.input.map.text).to.eql(map);
     });
 
+    it('accepts different name for UTF-8 encoding', () => {
+        let b64 = new Buffer(map).toString('base64');
+        let css = 'a{}\n/*# sourceMappingURL=data:application/json;' +
+                  'charset=utf8;base64,' + b64 + ' */';
+
+        expect(parse(css).source.input.map.text).to.eql(map);
+    });
+
     it('decodes URI maps', () => {
         let uri = 'data:application/json,' + decodeURI(map);
         let css = `a{}\n/*# sourceMappingURL=${ uri } */`;