it("match between Python and bokehjs", () => {
    let fail_count = 0
    const all_view_model_names = concat([keys(models_defaults), keys(widget_defaults)])
    for (const name of all_view_model_names) {
      const model = Models(name)
      const instance = new model({__deferred__: true})
      const attrs = instance.attributes_as_json(true, deep_value_to_json)
      strip_ids(attrs)

      const python_defaults = get_defaults(name)
      const bokehjs_defaults = attrs
      if (!check_matching_defaults(name, python_defaults, bokehjs_defaults)) {
        console.log(name)
        // console.log('python defaults:')
        // console.log(python_defaults)
        // console.log('bokehjs defaults:')
        // console.log(bokehjs_defaults)
        console.log(difference(keys(python_defaults), keys(bokehjs_defaults)))
        fail_count += 1
      }
    }

    console.error(`Python/bokehjs matching defaults problems: ${fail_count}`)
    expect(fail_count).to.equal(0)
  })

 it.skip("have all non-Widget view models from Python in the Models object", () => {
   const missing = []
   for (const name of keys(models_defaults)) {
     if (!(name in Models.registered_names())) {
       missing.push(name)
     }
   }
   for (const m of missing) {
     console.log(`'Models.${m}' not found but there's a Python model '${m}'`)
   }
   expect(missing.length).to.equal(0)
 })

 it("should update if columns update", () => {
   const r = new ColumnDataSource({data: {foo: [10, 20], bar:[10, 20]}})
   r.data.baz = [11, 21]
   expect(r.columns()).to.be.deep.equal(keys(r.data))
 })

 it("should have only id property", () => {
   const obj = new TestModel()
   expect(keys(obj.properties)).to.be.deep.equal(['id'])
   expect(keys(obj.attributes)).to.be.deep.equal(['id'])
 })

 it("should have 3 entries", () => {
   expect(keys(tmpl.DEFAULT_FORMATTERS).length).to.be.equal(3)
 })