Add charset support for dataUri base64

.jshintrc

@@ -41,6 +41,7 @@
     "define": false,
     "window": false,
     "atob": true,
-    "JSON": false
+    "JSON": false,
+    "TextDecoder": true
   }
 }

lib/source-map-resolve-node.js

@@ -70,9 +70,24 @@ function resolveSourceMapSync(code, codeUrl, read) {
   return mapData
 }
 
-var dataUriRegex = /^data:([^,;]*)(;[^,;]*)*(?:,(.*))?$/
+var dataUriRegex = /^data:(([^,;]*)(;[^,;]*)*)(?:,(.*))?$/
 var jsonMimeTypeRegex = /^(?:application|text)\/json$/
 
+function decodeBase64String(utfLabel, b64) {
+  var buf = base64ToBuf(b64);
+  var txt = new TextDecoder(utfLabel, {fatal: true}).decode(buf);
+  return txt; 
+  function base64ToBuf(str) {
+    var binStr = atob(str);
+    var len = binStr.length;
+    var arr = new Uint8Array(len);
+    for (var i = 0; i < len; i++) {
+      arr[i] = binStr.charCodeAt(i);
+    }
+    return arr;
+  }
+}
+
 function resolveSourceMapHelper(code, codeUrl) {
   codeUrl = urix(codeUrl)
 
@@ -83,9 +98,23 @@ function resolveSourceMapHelper(code, codeUrl) {
 
   var dataUri = url.match(dataUriRegex)
   if (dataUri) {
-    var mimeType = dataUri[1]
-    var lastParameter = dataUri[2] || ""
-    var encoded = dataUri[3] || ""
+    var mimeType = dataUri[2]
+    var lastParameter = dataUri[3] || ""
+    var encoded = dataUri[4] || ""
+    /**
+     * 
+     * @link https://tools.ietf.org/html/rfc2397#section-2
+     */
+    var defaultCharset = 'us-ascii'
+    var charset = dataUri[1]
+      .split(';')
+      .filter(function(x) {
+        return x.startsWith('charset=')
+      })
+      .map(function(x) {
+        return x.slice('charset='.length)
+      })
+      .pop() || defaultCharset
     var data = {
       sourceMappingURL: url,
       url: null,
@@ -98,7 +127,9 @@ function resolveSourceMapHelper(code, codeUrl) {
       throw error
     }
     data.map = parseMapToJSON(
-      lastParameter === ";base64" ? atob(encoded) : decodeURIComponent(encoded),
+      lastParameter === ";base64" ?
+        decodeBase64String(charset, encoded) :
+        decodeURIComponent(encoded),
       data
     )
     return data

source-map-resolve.js

@@ -78,9 +78,24 @@ void (function(root, factory) {
     return mapData
   }
 
-  var dataUriRegex = /^data:([^,;]*)(;[^,;]*)*(?:,(.*))?$/
+  var dataUriRegex = /^data:(([^,;]*)(;[^,;]*)*)(?:,(.*))?$/
   var jsonMimeTypeRegex = /^(?:application|text)\/json$/
 
+  function decodeBase64String(utfLabel, b64) {
+    var buf = base64ToBuf(b64);
+    var txt = new TextDecoder(utfLabel, {fatal: true}).decode(buf);
+    return txt; 
+    function base64ToBuf(str) {
+      var binStr = atob(str);
+      var len = binStr.length;
+      var arr = new Uint8Array(len);
+      for (var i = 0; i < len; i++) {
+        arr[i] = binStr.charCodeAt(i);
+      }
+      return arr;
+    }
+  }
+
   function resolveSourceMapHelper(code, codeUrl) {
     var url = sourceMappingURL.getFrom(code)
     if (!url) {
@@ -89,9 +104,23 @@ void (function(root, factory) {
 
     var dataUri = url.match(dataUriRegex)
     if (dataUri) {
-      var mimeType = dataUri[1]
-      var lastParameter = dataUri[2] || ""
-      var encoded = dataUri[3] || ""
+      var mimeType = dataUri[2]
+      var lastParameter = dataUri[3] || ""
+      var encoded = dataUri[4] || ""
+      /**
+       * 
+       * @link https://tools.ietf.org/html/rfc2397#section-2
+       */
+      var defaultCharset = 'us-ascii'
+      var charset = dataUri[1]
+        .split(';')
+        .filter(function(x) {
+          return x.startsWith('charset=')
+        })
+        .map(function(x) {
+          return x.slice('charset='.length)
+        })
+        .pop() || defaultCharset
       var data = {
         sourceMappingURL: url,
         url: null,
@@ -104,7 +133,9 @@ void (function(root, factory) {
         throw error
       }
       data.map = parseMapToJSON(
-        lastParameter === ";base64" ? atob(encoded) : decodeURIComponent(encoded),
+        lastParameter === ";base64" ?
+          decodeBase64String(charset, encoded) :
+          decodeURIComponent(encoded),
         data
       )
       return data