ServiceWorker: Remove iframes explicitly after a test is finished

third_party/WebKit/LayoutTests/http/tests/serviceworker/resources/test-helpers.js

 // Adapter for testharness.js-style tests with Service Workers
 
 function service_worker_unregister_and_register(test, url, scope) {
   if (!scope || scope.length == 0)
     return Promise.reject(new Error('tests must define a scope'));
 
   var options = { scope: scope };
   return service_worker_unregister(test, scope)
     .then(function() {
         return navigator.serviceWorker.register(url, options);
@@ skipping 26 matching lines @@
 // Rejection-specific helper that provides more details
 function unreached_rejection(test, prefix) {
   return test.step_func(function(error) {
       var reason = error.message || error.name || error;
       var error_prefix = prefix || 'unexpected rejection';
       assert_unreached(error_prefix + ': ' + reason);
     });
 }
 
 // Adds an iframe to the document and returns a promise that resolves to the
-// iframe when it finishes loading. The caller is responsible for removing the
-// iframe later if needed.
-function with_iframe(url) {
+// iframe when it finishes loading. When |reclaim_after_completion| is set to
+// |IFRAME_RECLAMATION.FALSE|, the caller is responsible for removing the iframe
+// later. Otherwise, the frame will be removed after all tests are finished.
+var IFRAME_RECLAMATION = Object.freeze({TRUE: true, FALSE: false});

[nhiroki, 2016/04/07 05:37:18]

How about using 'const' keyword instead?

  const DONT_RECLAIM_IFRAME = true;

And, maybe we can reduce the condition like this:

  function with_iframe(url, dont_reclaim_iframe) {
      // ...
      if (DONT_RECLAIM_IFRAME === dont_reclaim_iframe)
        return;
      add_completion_callback(function() { frame.remove(); });
  }

[falken, 2016/04/07 05:47:26]

Sorry for more drive-bys, just thought of this. Passing an optional options
object like:
{auto_remove: false}
seems a bit more common in the JS world?

[shimazu (google), 2016/04/07 06:53:55]

I think so, and fixed it.

+function with_iframe(url, reclaim_after_completion) {
   return new Promise(function(resolve) {
       var frame = document.createElement('iframe');
       frame.src = url;
       frame.onload = function() { resolve(frame); };
       document.body.appendChild(frame);
+      if (typeof reclaim_after_completion === 'undefined' ||
+          reclaim_after_completion === IFRAME_RECLAMATION.TRUE)
+        add_completion_callback(function() { frame.remove(); });
     });
 }
 
 function with_sandboxed_iframe(url, sandbox) {
   return new Promise(function(resolve) {
       var frame = document.createElement('iframe');
       frame.sandbox = sandbox;
       frame.src = url;
       frame.onload = function() { resolve(frame); };
       document.body.appendChild(frame);
@@ skipping 125 matching lines @@
 
 function login(test, local, remote) {
   var suffix = (local.indexOf("https") != -1) ? "s": "";
   return test_login(test, local, 'username1' + suffix, 'password1' + suffix,
                     'cookie1')
     .then(function() {
         return test_login(test, remote, 'username2' + suffix,
                           'password2' + suffix, 'cookie2');
       });
 }