ember/ember-3.16.10.template-compiler.js
// required keys are not removed.
required keys are not removed.
required keys are not removed .
function acceptRequired(node, name) {
      this.acceptKey(node, name);
      if (!node[name]) {
        throw new Exception(node.type + ' requires ' + name);
      }
    }
function acceptRequired ( node , name ) { this . acceptKey ( node , name ) ; if ( ! node [ name ] ) { throw new Exception ( node . type + ' requires ' + name ) ; } }
required keys are not removed.
required keys are not removed .