TypeError when updating a sub-property: Cannot use 'in' operator to search for 'value' in undefined

[justincy]

I'm getting a TypeError when attempting to update a sub-property:

Cannot use 'in' operator to search for 'value' in undefined
  TemplateInstance.Polymer.Templatizer._notifyPathUpImpl [as _notifyPathUp] at /components/polymer/polymer.html:3758
  TemplateInstance.Polymer.Base._addFeature._notifyPath at /components/polymer/polymer.html:2044
              TemplateInstance.<anonymous> at /components/polymer/polymer.html:1562
  TemplateInstance.Polymer.Base._addFeature._notifyListener at /components/polymer/polymer.html:2016
             trepo-core-person.<anonymous> at /components/polymer/polymer.html:1588
  trepo-core-person.Polymer.Base._addFeature.fire at /components/polymer/polymer.html:1335
  trepo-core-person.Polymer.Base._addFeature._notifyPathUp at /components/polymer/polymer.html:2208
  trepo-core-person.Polymer.Base._addFeature._notifyPath at /components/polymer/polymer.html:2044
  trepo-core-person.Polymer.Base._addFeature.set at /components/polymer/polymer.html:2100
                                 <unknown> at /components/trepo-core-person/trepo-core-person.html:173

The last line in the stack trace, trepo-core-person.html:173, looks like this:

self.set('value.id', personResponse.body.id);

I have verified that value exists as an empty object {} and personResponse.body.id has a value.

This is only happening when running tests with wct. It's using Polymer v1.2.3.

[justincy]

This error only occurs when using test-fixture. It appears that the _parentProps is not being set properly when the template is processed and the element is stamped into the DOM. Then when the notification for the sub-property change is processed it blows up.

Everything works as intended if I don't use test-fixture.

[justincy]

This also only happens if the sub-property's root value is bound inside the text-fixture, such as:

  <test-fixture id="element">
    <template is="dom-template">
      <my-element data="{{data}}"></my-element>
    </template>
  </test-fixture>

[dfreedm]

This seems more like an issue with test-fixture not handling data binding. @cdata, thoughts?

[cdata]

I concur that this may be related to a test-fixture problem, although I would also like to see a reduced test case so that we can actually explore the problem directly. @justincy would you be willing to provide a JSBin?

[justincy]

Sorry but I'm not involved with that code at the moment. Plus I stated earlier that is only occurs when using wct from the cli. I can't remember whether that's true, but if it is then jsbin isn't going to help.

[Sleeckx]

@cdata, I encountered the same issue and managed to produce a small test-case without wct:

http://jsbin.com/dunikitije/edit?html,console,output

The issue is fixed when I change the test property binding on <my-child> from two-way to one-way.
As in: <my-child test="[[test]]"></my-child>

[cdata]

@Sleeckx Thanks for the research. But, if you don't use test-fixture in your test case, I think that the source of the issue is still inconclusive.

[Sleeckx]

@cdata, I respectfully disagree. As @justincy said in his last comment:

I stated earlier that is only occurs when using wct from the cli. I can't remember whether that's true

Also, if it only occurred while they were using test-fixture it is still no guarantee that the component ever called set or notifyPath in normal use cases. Or, more importantly, that my-element was at any time wrapped in a dom-template when not using test-fixture.

From what I saw, the issue is mainly related to the fact that calling set('xxx' or notifyPath('xxx' on the element causes the two-way binding to fire a xxx-changed, which gets bubbled to the dom-template, which in turn incorrectly assumes that it has the _parentProps field set on the template instance.

[Ortham]

I'm also getting this error when trying to bind the opened attribute of a <paper-menu-button> to an item in an <iron-list> (which uses the Templatizer behaviour). For example:

  <iron-list id="list">
    <template>
      <div>
        [[item.name]]
        <paper-menu-button opened="{{item.isMenuOpen}}">
          <paper-icon-button icon="more-vert" class="dropdown-trigger"></paper-icon-button>
          <paper-menu class="dropdown-content">
            Bar
          </paper-menu>
        </paper-menu-button>
      </div>
    </template>
  </iron-list>
  <script>
    const items = [{
      name: 'foo',
      isMenuOpen: false,
    }];
    document.getElementById('list').items = items;
  </script>

Clicking on the button displays the menu, but also logs the reported error to the console. Clicking on the displayed menu also logs the reported error to the console.

[cdata]

@Sleeckx He also said:

This error only occurs when using test-fixture.
Everything works as intended if I don't use test-fixture.

Even if the bug is not related to test-fixture, I would like the reporter to restate the issue in an actionable way and provide a reduced test case. Thank you!

[TimvdLippe]

Thanks for the issue. It has been a great while since this issue was opened. Sadly, this issue misses a live reproduction with Polymer 2 for us to be able to debug and potentially fix. Polymer 2 fixes a large amount of issues, probably including this one as well.

Please see CONTRIBUTING.md for guidelines on filing issues. You can start from this jsBin template as a starting point and link it in the issue template under "Live Demo".

Feel free to file a new issue following these instructions if you can still reproduce this issue with Polymer 2. Thank you!