function validate(awaitNode) {
			if (awaitNode.type === "ForOfStatement" && !awaitNode.await) {
				return;
			}

			let node = awaitNode;
			let parent = node.parent;

			while (parent && !isBoundary(parent)) {
				if (isLooped(node, parent)) {
					context.report({
						node: awaitNode,
						messageId: "unexpectedAwait",
					});
					return;
				}
				node = parent;
				parent = parent.parent;
			}
		}
Validate an await expression.
@param {ASTNode} awaitNode An AwaitExpression or ForOfStatement node to validate.
@returns {void}