Fix utf8 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

@@ -71,8 +71,45 @@ function resolveSourceMapSync(code, codeUrl, read) {
 }
 
 var dataUriRegex = /^data:([^,;]*)(;[^,;]*)*(?:,(.*))?$/
+
+/**
+ * The media type for JSON text is application/json.
+ * 
+ * {@link https://tools.ietf.org/html/rfc8259#section-11 | IANA Considerations }
+ * 
+ * `text/json` is non-standard media type
+ */
 var jsonMimeTypeRegex = /^(?:application|text)\/json$/
 
+/**
+ * JSON text exchanged between systems that are not part of a closed ecosystem
+ * MUST be encoded using UTF-8.
+ * 
+ * {@link https://tools.ietf.org/html/rfc8259#section-8.1 | Character Encoding}
+ */
+var jsonCharacterEncoding = "utf-8"
+
+function base64ToBuf(b64) {
+  var binStr = atob(b64)
+  var len = binStr.length
+  var arr = new Uint8Array(len)
+  for (var i = 0; i < len; i++) {
+    arr[i] = binStr.charCodeAt(i)
+  }
+  return arr
+}
+
+function decodeBase64String(b64) {
+  if (typeof TextDecoder === "undefined" || typeof Uint8Array === "undefined") {
+    return atob(b64)
+  }
+  var buf = base64ToBuf(b64);
+  // Note: `decoder.decode` method will throw a `DOMException` with the
+  // `"EncodingError"` value when an coding error is found.
+  var decoder = new TextDecoder(jsonCharacterEncoding, {fatal: true})
+  return decoder.decode(buf); 
+}
+
 function resolveSourceMapHelper(code, codeUrl) {
   codeUrl = urix(codeUrl)
 
@@ -83,7 +120,7 @@ function resolveSourceMapHelper(code, codeUrl) {
 
   var dataUri = url.match(dataUriRegex)
   if (dataUri) {
-    var mimeType = dataUri[1]
+    var mimeType = dataUri[1] || "text/plain"
     var lastParameter = dataUri[2] || ""
     var encoded = dataUri[3] || ""
     var data = {
@@ -93,12 +130,12 @@ function resolveSourceMapHelper(code, codeUrl) {
       map: encoded
     }
     if (!jsonMimeTypeRegex.test(mimeType)) {
-      var error = new Error("Unuseful data uri mime type: " + (mimeType || "text/plain"))
+      var error = new Error("Unuseful data uri mime type: " + mimeType)
       error.sourceMapData = data
       throw error
     }
     data.map = parseMapToJSON(
-      lastParameter === ";base64" ? atob(encoded) : decodeURIComponent(encoded),
+      lastParameter === ";base64" ? decodeBase64String(encoded) : decodeURIComponent(encoded),
       data
     )
     return data

source-map-resolve.js

@@ -79,8 +79,45 @@ void (function(root, factory) {
   }
 
   var dataUriRegex = /^data:([^,;]*)(;[^,;]*)*(?:,(.*))?$/
+
+  /**
+   * The media type for JSON text is application/json.
+   * 
+   * {@link https://tools.ietf.org/html/rfc8259#section-11 | IANA Considerations }
+   * 
+   * `text/json` is non-standard media type
+   */
   var jsonMimeTypeRegex = /^(?:application|text)\/json$/
 
+  /**
+   * JSON text exchanged between systems that are not part of a closed ecosystem
+   * MUST be encoded using UTF-8.
+   * 
+   * {@link https://tools.ietf.org/html/rfc8259#section-8.1 | Character Encoding}
+   */
+  var jsonCharacterEncoding = "utf-8"
+
+  function base64ToBuf(b64) {
+    var binStr = atob(b64)
+    var len = binStr.length
+    var arr = new Uint8Array(len)
+    for (var i = 0; i < len; i++) {
+      arr[i] = binStr.charCodeAt(i)
+    }
+    return arr
+  }
+
+  function decodeBase64String(b64) {
+    if (typeof TextDecoder === "undefined" || typeof Uint8Array === "undefined") {
+      return atob(b64)
+    }
+    var buf = base64ToBuf(b64);
+    // Note: `decoder.decode` method will throw a `DOMException` with the
+    // `"EncodingError"` value when an coding error is found.
+    var decoder = new TextDecoder(jsonCharacterEncoding, {fatal: true})
+    return decoder.decode(buf); 
+  }
+
   function resolveSourceMapHelper(code, codeUrl) {
     var url = sourceMappingURL.getFrom(code)
     if (!url) {
@@ -89,7 +126,7 @@ void (function(root, factory) {
 
     var dataUri = url.match(dataUriRegex)
     if (dataUri) {
-      var mimeType = dataUri[1]
+      var mimeType = dataUri[1] || "text/plain"
       var lastParameter = dataUri[2] || ""
       var encoded = dataUri[3] || ""
       var data = {
@@ -99,12 +136,12 @@ void (function(root, factory) {
         map: encoded
       }
       if (!jsonMimeTypeRegex.test(mimeType)) {
-        var error = new Error("Unuseful data uri mime type: " + (mimeType || "text/plain"))
+        var error = new Error("Unuseful data uri mime type: " + mimeType)
         error.sourceMapData = data
         throw error
       }
       data.map = parseMapToJSON(
-        lastParameter === ";base64" ? atob(encoded) : decodeURIComponent(encoded),
+        lastParameter === ";base64" ? decodeBase64String(encoded) : decodeURIComponent(encoded),
         data
       )
       return data

test/source-map-resolve.js

@@ -61,6 +61,12 @@ var map = {
     sources:  [],
     names:    []
   },
+  utf8 : {
+    mappings:       "AAAA",
+    sources:        ["foo.js"],
+    sourcesContent: ["中文😊"],
+    names:          []
+  },
   empty: {}
 }
 map.simpleString = JSON.stringify(map.simple)
@@ -75,7 +81,7 @@ var code = {
                         "%7B%22mappings%22%3A%22AAAA%22%2C%22sources%22%3A%5B%22" +
                         "foo.js%22%5D%2C%22names%22%3A%5B%5D%7D"),
   base64:             u("data:application/json;base64," +
-                        "eyJtYXBwaW5ncyI6IkFBQUEiLCJzb3VyY2VzIjpbImZvby5qcyJdLCJuYW1lcyI6W119"),
+                        "eyJtYXBwaW5ncyI6IkFBQUEiLCJzb3VyY2VzIjpbImZvby5qcyJdLCJzb3VyY2VzQ29udGVudCI6WyLkuK3mlofwn5iKIl0sIm5hbWVzIjpbXX0="), // jshint ignore:line
   dataUriText:        u("data:text/json," +
                         "%7B%22mappings%22%3A%22AAAA%22%2C%22sources%22%3A%5B%22" +
                         "foo.js%22%5D%2C%22names%22%3A%5B%5D%7D"),
@@ -171,10 +177,10 @@ function testResolveSourceMap(method, sync) {
       t.error(error)
       t.deepEqual(result, {
         sourceMappingURL:  "data:application/json;base64," +
-                           "eyJtYXBwaW5ncyI6IkFBQUEiLCJzb3VyY2VzIjpbImZvby5qcyJdLCJuYW1lcyI6W119",
+                           "eyJtYXBwaW5ncyI6IkFBQUEiLCJzb3VyY2VzIjpbImZvby5qcyJdLCJzb3VyY2VzQ29udGVudCI6WyLkuK3mlofwn5iKIl0sIm5hbWVzIjpbXX0=", // jshint ignore:line
         url:               null,
         sourcesRelativeTo: codeUrl,
-        map:               map.simple
+        map:               map.utf8
       }, "base64")
       isAsync()
     })
@@ -683,12 +689,12 @@ function testResolve(method, sync) {
       t.error(error)
       t.deepEqual(result, {
         sourceMappingURL:  "data:application/json;base64," +
-                           "eyJtYXBwaW5ncyI6IkFBQUEiLCJzb3VyY2VzIjpbImZvby5qcyJdLCJuYW1lcyI6W119",
+                           "eyJtYXBwaW5ncyI6IkFBQUEiLCJzb3VyY2VzIjpbImZvby5qcyJdLCJzb3VyY2VzQ29udGVudCI6WyLkuK3mlofwn5iKIl0sIm5hbWVzIjpbXX0=", // jshint ignore:line
         url:               null,
         sourcesRelativeTo: codeUrl,
-        map:               map.simple,
+        map:               map.utf8,
         sourcesResolved:   ["http://example.com/a/b/c/foo.js"],
-        sourcesContent:    ["http://example.com/a/b/c/foo.js"]
+        sourcesContent:    ["中文😊"]
       }, "base64")
       isAsync()
     })