<!DOCTYPE html>
<meta name="author" title="Takayoshi Kochi" href="mailto:kochi@chromium.org">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<div id=log></div>
<div id="parent">
  <template id="tmpl"><span>Happy Templating!</span></template>
</div>
<script>
test(() => {
  var parent = document.getElementById('parent');
  var tmpl = document.getElementById('tmpl');

  assert_equals(tmpl.innerHTML, '<span>Happy Templating!</span>');
  var span = tmpl.content.querySelector('span');

  // Hierarchy checks at various combinations.
  assert_throws_dom('HierarchyRequestError', () => {
    tmpl.content.appendChild(parent);
  }, 'Template content should throw if any of ancestor is being appended.');
  assert_throws_dom('HierarchyRequestError', () => {
    tmpl.content.appendChild(tmpl);
  }, 'Template content should throw if its host is being appended.');
  assert_throws_dom('HierarchyRequestError', () => {
    span.appendChild(parent);
  }, 'Template content child should throw if any of ancestor is being appended.');
  assert_throws_dom('HierarchyRequestError', () => {
    span.appendChild(tmpl);
  }, 'Template content child should throw template\'s host is being appended.');
}, "Template content should throw when its ancestor is being appended.");

test(() => {
  var parent = document.getElementById('parent');
  var tmpl = document.getElementById('tmpl');

  assert_equals(tmpl.innerHTML, '<span>Happy Templating!</span>');
  var span = tmpl.content.querySelector('span');

  var tmpl_doc = tmpl.content.ownerDocument;
  assert_equals(tmpl.ownerDocument, document);
  assert_not_equals(tmpl_doc, document);

  var new_doc = document.implementation.createHTMLDocument();
  assert_not_equals(new_doc, document);
  assert_not_equals(new_doc, tmpl_doc);

  // Try moving tmpl.content to new_doc and check the results.
  const tmplContentNodeDocument = tmpl.content.ownerDocument;
  const tmplContentAdoptResult = new_doc.adoptNode(tmpl.content);
  assert_equals(tmpl.content, tmplContentAdoptResult);
  assert_equals(tmpl.ownerDocument, document);
  assert_equals(tmpl.content.ownerDocument, tmplContentNodeDocument);

  // Hierarchy checks at various combinations.
  assert_throws_dom('HierarchyRequestError', () => {
    tmpl.content.appendChild(parent);
  }, 'Template content should throw if any of ancestor is being appended.');
  assert_throws_dom('HierarchyRequestError', () => {
    tmpl.content.appendChild(tmpl);
  }, 'Template content should throw if its host is being appended.');
  assert_throws_dom('HierarchyRequestError', () => {
    span.appendChild(parent);
  }, 'Template content child should throw if any of ancestor is being appended.');
  assert_throws_dom('HierarchyRequestError', () => {
    span.appendChild(tmpl);
  }, 'Template content child should throw template\'s host is being appended.');

  // Sanity check: template.content before and after move.
  var tmpl_content_reference = tmpl.content;
  assert_equals(tmpl.content.firstChild, span,
                '<span> should be kept until it is removed, even after ' +
                'adopted to another document.');
  new_doc.body.appendChild(tmpl.content);
  assert_equals(tmpl.content.firstChild, null,
                '<span> should be removed from template content.');
  assert_equals(tmpl_content_reference, tmpl.content,
                'template.content should be identical before and after ' +
                'moving its children.');
}, 'Template content should throw exception when its ancestor in ' +
   'a different document but connected via host is being append.');
</script>
