JS: Added string encoding/decoding tests for UTF-8

js/binary/decoder_test.js

@@ -209,7 +209,30 @@ describe('binaryDecoderTest', function() {
     assertEquals(hashC, decoder.readFixedHash64());
     assertEquals(hashD, decoder.readFixedHash64());
   });
+  
+  /**
+   * Test encoding and decoding utf-8.
+   */
+   it('testUtf8', function() {
+    var encoder = new jspb.BinaryEncoder();
 
+    var ascii = "ASCII should work in 3, 2, 1..."
+    var utf8_two_bytes = "©";
+    var utf8_tree_bytes = "❄";
+    var utf8_four_bytes = "😁";
+    
+    encoder.writeString(ascii);
+    encoder.writeString(utf8_two_bytes);
+    encoder.writeString(utf8_tree_bytes);
+    encoder.writeString(utf8_four_bytes);
+    
+    var decoder = jspb.BinaryDecoder.alloc(encoder.end());
+    
+    assertEquals(ascii, decoder.readString(ascii.length));
+    assertEquals(utf8_two_bytes, decoder.readString(utf8_two_bytes.length));
+    assertEquals(utf8_tree_bytes, decoder.readString(utf8_tree_bytes.length));
+    assertEquals(utf8_four_bytes, decoder.readString(utf8_four_bytes.length));
+   });
 
   /**
    * Verifies that misuse of the decoder class triggers assertions.