code: function(node) {
  				var scope = context.getScope(),
  					features = context.ecmaFeatures || {};
  
  				stack.push({
  					init: true,
  					node: node,
  					valid: !(
  						scope.isStrict ||
  						node.sourceType === "module" ||
  						(features.globalReturn && scope.childScopes[0].isStrict)
  					)
  				});
  			}
docs: /*
  'this' is invalid only under strict mode.
  Modules is always strict mode.