imag/lib/etc/libimagutil/src/variants.rs

78 lines
2.3 KiB
Rust

//
// imag - the personal information management suite for the commandline
// Copyright (C) 2015, 2016 Matthias Beyer <mail@beyermatthias.de> and contributors
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; version
// 2.1 of the License.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
//
/**
* Generate variants of a base value by applying parts
*
* Example:
*
* ```ignore
* generate_variants(path, vec!["foo", "bar", "baz"], |b, v| {
* let b = b.clone();
* b.push(v);
* b
* })
*
* ```
*
*/
pub fn generate_variants<A, B, C, F>(base: A, modders: Vec<B>, f: &F)
-> Vec<C>
where
F: Fn(&A, B) -> C
{
modders.into_iter().map(|m| f(&base, m)).collect()
}
#[cfg(test)]
mod test {
use super::generate_variants;
#[test]
fn test_variants_simple() {
let base = 1;
let vars = vec![0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
let res = generate_variants(base, vars, &|base, var| base + var);
assert!(res.len() == 11, format!("Length is {} instead of 11", res.len()));
assert!(res.iter().all(|i| *i > 0));
assert!(res == vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11])
}
#[test]
fn test_variants_pathes() {
use std::path::PathBuf;
let base = PathBuf::from("/");
let vars = vec!["foo", "bar", "baz"];
let res = generate_variants(base, vars, &|base, var| {
let mut base = base.clone();
base.push(var);
base
});
assert!(res.len() == 3, format!("Length is {} instead of 3", res.len()));
let eq_vec = vec!["/foo", "/bar", "/baz"];
let eq = eq_vec.iter().map(PathBuf::from);
assert!(res.into_iter().zip(eq).all(|(orig, equi)| orig == equi));
}
}