Netlify-cms: TypeError: e.get is not a function

[Kakise]

- Do you want to request a feature or report a bug?
Bug

- Please mention your versions where applicable.

Netlify CMS version: 1.7.0
Browser version: Latest Chrome Canary (ran in Chrome OS)

- Please link or paste your config.yml below if applicable.
-> https://github.com/Kakise/Blog/tree/master/source/admin

Log: kakise.me-1526163368102.log

[tech4him1]

Looks like the main error in the log is:

react-dom.production.min.js:163 TypeError: e.get is not a function
    at t.value (ListControl.js:204)
    at renderItem (ListControl.js:245)
    at immutable.js:3016
    at immutable.js:1377
    at ue.iterate.de.iterate (immutable.js:1726)
    at le.__iterate (immutable.js:1375)
    at n.Qe.r.__iterateUncached (immutable.js:3015)
    at z (immutable.js:604)
    at n.x.__iterate (immutable.js:274)
    at n.forEach (immutable.js:4381)

[tech4him1]

@Kakise The "Tags" field under your config is set to widget type list, but doesn't have any sub-fields specified. I'm guessing this is the problem here.

[Kakise]

That was the problem. I had to change from list to object. It is now working, thanks.

[caseyjkey]

I am having a similar issue with my "Introduction" file collection. Here is the config:

backend:
  name: github
  repo: caseykey/caseykey.github.io
  branch: source
  site_domain: quirky-bassi-7f760a.netlify.com

site_url: https://caseyjkey.com
display_url: https://caseyjkey.com

public_folder: "/src/images/"
media_folder: "/src/images/"

collections:
  - label: "Sections"
    name: "sections"
    files:
    - label: "Introduction"
      name: "introduction"
      file: "src/data/introduction.json"
      fields:
        - {label: "Greeting", name: "greeting", widget: "string", default: "Hey! I am"}
        - {label: "Name", name: "name", widget: "string", default: "Casey Key"}
        - label: "Descriptions"
          label_singular: "description"
          name: "descriptions"
          widget: "list" 
          field:
            - label: "Description"
              name: "description"
              widget: "object"
              fields:
                - {label: "Description", name: "header", widget: "string"}
                - {label: "Example", name: "subheader", widget: "string"} 

This shows me a list of "No undefined". When this "No undefined" is opened, it is a string entry that is labeled, "undefined". I want a list of objects, each labeled "Description" with two string fields.

Why am I only seeing one "undefined" string field for each object, and why is each object "No undefined"? When I try to submit an entry, I get the original error of e.get is not a function.

[tomrutgers]

The field property takes an object, not a list: https://www.netlifycms.org/docs/widgets/#list

collections:
  - label: "Sections"
    name: "sections"
    files:
    - label: "Introduction"
      name: "introduction"
      file: "src/data/introduction.json"
      fields:
        - {label: "Greeting", name: "greeting", widget: "string", default: "Hey! I am"}
        - {label: "Name", name: "name", widget: "string", default: "Casey Key"}
        - label: "Descriptions"
          label_singular: "description"
          name: "descriptions"
          widget: "list" 
          field: {
            label: "Description",
            name: "description",
            widget: "object",
            fields:
              - {label: "Description", name: "header", widget: "string"}
              - {label: "Example", name: "subheader", widget: "string"}
          }

[caseyjkey]

@tomrutgers

I am getting this error now:

YAMLException: missed comma between flow collection entries at line 32, column 15:
                  - {label: "Description", name: " ... 

It expects a comma instead of the -.

I tried this:

  - {label: "Greeting", name: "greeting", widget: "string", default: "Hey! I am"}
        - {label: "Name", name: "name", widget: "string", default: "Casey Key"}
        - label: "Descriptions"
          label_singular: "description"
          name: "descriptions"
          widget: "list" 
          field: {
              label: "Description",
              name: "description",
              widget: "object",
              field: {
                  {label: "Description", name: "header", widget: "string"},
                  {label: "Example", name: "subheader", widget: "string"} 
              }
          }

Which results in this error:

YAMLException: duplicated mapping key at line 34, column 15:
                  }

Not sure what to do as objects require a nested list of fields

EDIT: Fixed it using https://yaml-online-parser.appspot.com/