Netlify-cms: r.get is not a function (Collection/Edit page)

[leeandher]

Describe the bug

While trying to make an edit to an existing collection item (standard blog post) I was prompted to use 'a local cached version' instead. I dismissed this prompt and the application seemed to crash. I can no longer edit any collection items, not just the one I'd initially selected

To Reproduce


_I'm not sure how this happened, but I believe it went something like this_

1. Have a cached version of Netlify CMS open (connected to production)
2. Make an edit to a collection
3. Close your local dev server
4. Restart dev server
5. Open NCMS again, in a different tab
6. Try to edit the same blog post (still open/cached in the other tab)

_Either this, or it messed up because I just pushed to GH right before this._

I believe it's something wrong with my config.yml, specifically the tags section, since removing that field seems to solve the issue.
I have existing front matter called tags with values like ["coding", "personal", "announcement"], o maybe that doesn't play well with NCMS?

Expected behavior

Be able to make edits to my collections, or at least refresh the page to have the error go away

Screenshots

The crash screen:

Console print-out:

Applicable Versions:

• Netlify CMS version: ^2.8.0
• Git provider: GH
• OS: Win10
• Browser version: Chrome 73
  
• Node.JS version: 10.13.0

CMS configuration

backend:
  name: github
  repo: leeandher/leander.xyz
  branch: dev 

# backend:
#  repo: test-repo

media_folder: static/assets
public_folder: assets

collections:
  - name: blog
    label: Blog
    folder: src/pages/blog
    create: true
    fields:
      - { name: path, label: Path, widget: string }
      - { name: date, label: Date, widget: date }
      - { name: title, label: Title, widget: string }
      - { name: preview, label: Preview, widget: text }
      - { name: body, label: Body, widget: markdown }
      - {
          name: tags,
          label: Tags,
          widget: list,
          fields: { name: tag, label: Tag, widget: string },
        }

Additional context

[leeandher]

Restarting the dev server didn't fix this either :/

[leeandher]

Since my assets/ folder wasn't initialized, it 404'd in console, but that wasn't the cause, the problem still persists:

[leeandher]

EDIT: modified steps to reproduce

[erquhart]

Immediate fix is to delete your localstorage on the dev url.

_{Sent with GitHawk}

[erquhart]

Oh wait you're on 2.8.0 - try bumping to 2.9.0.

_{Sent with GitHawk}

[leeandher]

@erquhart Deleted localStorage and bumped version, I'm still getting the bug :/

[leeandher]

@erquhart Ahhhhh, I was just being dumb. I had a list widget with a custom field, but only one: string. If you add the fields property with an 's' instead of field for only one custom widget, the application seems to break.

[tomrutgers]

The fields property needs an array instead of an object.