| // Licensed to the Apache Software Foundation (ASF) under one |
| // or more contributor license agreements. See the NOTICE file |
| // distributed with this work for additional information |
| // regarding copyright ownership. The ASF licenses this file |
| // to you under the Apache License, Version 2.0 (the |
| // "License"); you may not use this file except in compliance |
| // with the License. You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, |
| // software distributed under the License is distributed on an |
| // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| // KIND, either express or implied. See the License for the |
| // specific language governing permissions and limitations |
| // under the License.. |
| |
| use std::fmt::Display; |
| use std::cell::RefCell; |
| |
| #[derive(Default)] |
| pub struct Ctxt { |
| errors: RefCell<Option<Vec<String>>>, |
| } |
| |
| impl Ctxt { |
| pub fn new() -> Self { |
| Ctxt { errors: RefCell::new(Some(Vec::new())) } |
| } |
| |
| pub fn error<T: Display>(&self, msg: T) { |
| self.errors |
| .borrow_mut() |
| .as_mut() |
| .unwrap() |
| .push(msg.to_string()); |
| } |
| |
| pub fn check(self) -> Result<(), String> { |
| let mut errors = self.errors.borrow_mut().take().unwrap(); |
| match errors.len() { |
| 0 => Ok(()), |
| 1 => Err(errors.pop().unwrap()), |
| n => { |
| let mut msg = format!("{} errors:", n); |
| for err in errors { |
| msg.push_str("\n\t# "); |
| msg.push_str(&err); |
| } |
| Err(msg) |
| } |
| } |
| } |
| } |
| |
| impl Drop for Ctxt { |
| fn drop(&mut self) { |
| if self.errors.borrow().is_some() { |
| panic!("forgot to check for errors"); |
| } |
| } |
| } |