#[macro_use] extern crate pretty_assertions; #[macro_use] extern crate derive_builder; use std::num::ParseIntError; #[derive(Debug, PartialEq, Default, Builder, Clone)] pub struct Lorem { #[builder(field(type = "Option", build = "self.ipsum.unwrap_or(42) + 1"))] ipsum: usize, #[builder(setter(into), field(type = "String", build = "self.dolor.parse()?"))] dolor: u32, } impl From for LoremBuilderError { fn from(e: ParseIntError) -> LoremBuilderError { LoremBuilderError::ValidationError(e.to_string()) } } #[test] fn custom_fields() { let x = LoremBuilder::default().dolor("7").build().unwrap(); assert_eq!( x, Lorem { ipsum: 43, dolor: 7, } ); let x = LoremBuilder::default() .ipsum(Some(12)) .dolor("66") .build() .unwrap(); assert_eq!( x, Lorem { ipsum: 13, dolor: 66, } ); let x = LoremBuilder::default().build().unwrap_err().to_string(); assert_eq!(x, "cannot parse integer from empty string"); }