| // Copyright (c) 2017 Baidu, Inc. All Rights Reserved. |
| // |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions |
| // are met: |
| // |
| // * Redistributions of source code must retain the above copyright |
| // notice, this list of conditions and the following disclaimer. |
| // * Redistributions in binary form must reproduce the above copyright |
| // notice, this list of conditions and the following disclaimer in |
| // the documentation and/or other materials provided with the |
| // distribution. |
| // * Neither the name of Baidu, Inc., nor the names of its |
| // contributors may be used to endorse or promote products derived |
| // from this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| 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"); |
| } |
| } |
| } |