third_party/web_platform_tests/FileAPI/reading-data-section/filereader_result.html

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title>FileAPI Test: filereader_result</title>
    <link rel="author" title="Intel" href="http://www.intel.com">
    <link rel="help" href="http://dev.w3.org/2006/webapi/FileAPI/#filedata-attr">
    <script src="/resources/testharness.js"></script>
    <script src="/resources/testharnessreport.js"></script>
  </head>
  <body>
    <div id="log"></div>

    <script>
    var blob;
    setup(function() {
      blob = new Blob(["This test the result attribute"]);
    });

    async_test(function() {
      var readText = new FileReader();
      assert_equals(readText.result, null);

      readText.onloadend = this.step_func(function(evt) {
        assert_equals(typeof readText.result, "string", "The result type is string");
        assert_equals(readText.result, "This test the result attribute", "The result is correct");
        this.done();
      });

      readText.readAsText(blob);
    }, "readAsText");

    async_test(function() {
      var readDataURL = new FileReader();
      assert_equals(readDataURL.result, null);

      readDataURL.onloadend = this.step_func(function(evt) {
        assert_equals(typeof readDataURL.result, "string", "The result type is string");
        assert_true(readDataURL.result.indexOf("VGhpcyB0ZXN0IHRoZSByZXN1bHQgYXR0cmlidXRl") != -1, "return the right base64 string");
        this.done();
      });

      readDataURL.readAsDataURL(blob);
    }, "readAsDataURL");

    async_test(function() {
      var readArrayBuffer = new FileReader();
      assert_equals(readArrayBuffer.result, null);

      readArrayBuffer.onloadend = this.step_func(function(evt) {
        assert_true(readArrayBuffer.result instanceof ArrayBuffer, "The result is instanceof ArrayBuffer");
        this.done();
      });

      readArrayBuffer.readAsArrayBuffer(blob);
    }, "readAsArrayBuffer");
    </script>
  </body>
</html>