angle-bracket-hasBlock

application.controller.js

import Ember from 'ember';

export default Ember.Controller.extend({
  value: 'test'
});

application.template.hbs

Short closed: <glimmer-component value={{value}} expected="test" />
<br>
Closing tag: <glimmer-component value={{value}} expected="test"></glimmer-component>
<br>
\{{component}} helper invocation: {{component "<glimmer-component>" value=value expected="test"}}

glimmer-component.component.js

import Ember from 'ember';

export default Ember.GlimmerComponent.extend();

glimmer-component.template.hbs

<span>{{if hasBlock 'Block' 'Not a block'}}</span>

twiddle.json

{
  "version": "0.4.16",
  "EmberENV": {
    "FEATURES": {
      "ember-htmlbars-component-generation": true
    }
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "canary",
    "ember-data": "https://cdnjs.cloudflare.com/ajax/libs/ember-data.js/2.1.0/ember-data.js",
    "ember-template-compiler": "canary"
  }
}