100-exercises-to-learn-rust/exercises/05_ticket_v2/14_source/src/lib.rs

77 lines
2.3 KiB
Rust

use crate::status::Status;
// We've seen how to declare modules in one of the earliest exercises, but
// we haven't seen how to extract them into separate files.
// Let's fix that now!
//
// In the simplest case, when the extracted module is a single file, it is enough to
// create a new file with the same name as the module and move the module content there.
// The module file should be placed in the same directory as the file that declares the module.
// In this case, `src/lib.rs`, thus `status.rs` should be placed in the `src` directory.
mod status;
// TODO: Add a new error variant to `TicketNewError` for when the status string is invalid.
// When calling `source` on an error of that variant, it should return a `ParseStatusError` rather than `None`.
#[derive(Debug, thiserror::Error)]
pub enum TicketNewError {
#[error("Title cannot be empty")]
TitleCannotBeEmpty,
#[error("Title cannot be longer than 50 characters")]
TitleTooLong,
#[error("Description cannot be empty")]
DescriptionCannotBeEmpty,
#[error("Description cannot be longer than 500 characters")]
DescriptionTooLong,
}
#[derive(Debug, PartialEq, Clone)]
pub struct Ticket {
title: String,
description: String,
status: Status,
}
impl Ticket {
pub fn new(title: String, description: String, status: String) -> Result<Self, TicketNewError> {
if title.is_empty() {
return Err(TicketNewError::TitleCannotBeEmpty);
}
if title.len() > 50 {
return Err(TicketNewError::TitleTooLong);
}
if description.is_empty() {
return Err(TicketNewError::DescriptionCannotBeEmpty);
}
if description.len() > 500 {
return Err(TicketNewError::DescriptionTooLong);
}
// TODO: Parse the status string into a `Status` enum.
Ok(Ticket {
title,
description,
status,
})
}
}
#[cfg(test)]
mod tests {
use common::{valid_description, valid_title};
use std::error::Error;
use super::*;
#[test]
fn invalid_status() {
let err = Ticket::new(valid_title(), valid_description(), "invalid".into()).unwrap_err();
assert_eq!(
err.to_string(),
"`invalid` is not a valid status. Use one of: ToDo, InProgress, Done"
);
assert!(err.source().is_some());
}
}