Fix embedding source maps with non-ASCII characters (#471)

Closes #457

CHANGELOG.md

@@ -3,6 +3,11 @@
 * Properly generate source maps for stylesheets that emit `@charset`
   declarations.
 
+### Command-Line Interface
+
+* Don't error out when passing `--embed-source-maps` along with
+  `--embed-sources` for stylesheets that contain non-ASCII characters.
+
 ## 1.13.2
 
 * Properly parse `:nth-child()` and `:nth-last-child()` selectors with

lib/src/executable/compile_stylesheet.dart

@@ -142,7 +142,8 @@ String _writeSourceMap(
 
   Uri url;
   if (options.embedSourceMap) {
-    url = new Uri.dataFromString(sourceMapText, mimeType: 'application/json');
+    url = new Uri.dataFromString(sourceMapText,
+        mimeType: 'application/json', encoding: utf8);
   } else {
     var sourceMapPath = destination + '.map';
     ensureDir(p.dirname(sourceMapPath));

pubspec.yaml

@@ -1,5 +1,5 @@
 name: sass
-version: 1.13.3-dev
+version: 1.13.3
 description: A Sass implementation in Dart.
 author: Dart Team <misc@dartlang.org>
 homepage: https://github.com/sass/dart-sass

test/cli/shared/source_maps.dart

@@ -274,6 +274,23 @@ void sharedTests(Future<TestProcess> runSass(Iterable<String> arguments)) {
       test("doesn't generate a source map file", () async {
         await d.nothing("out.css.map").validate();
       });
+
+      // Regression test for #457.
+      test("--embed-sources works with non-ASCII characters", () async {
+        await d.file("test.scss", "a {b: '▼'}").create();
+        await (await runSass([
+          "--embed-source-map",
+          "--embed-sources",
+          "test.scss",
+          "out.css"
+        ]))
+            .shouldExit(0);
+        var css = readFile(d.path("out.css"));
+        map = embeddedSourceMap(css);
+
+        expect(map, containsPair("sources", ["test.scss"]));
+        expect(map, containsPair("sourcesContent", ["a {b: '▼'}"]));
+      });
     });
 
     group("with the target in a different directory", () {