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mod money;
mod obligation;
mod payment;
mod person;
mod solver;
pub use money::*;
pub use obligation::*;
pub use payment::*;
pub use person::*;
pub use solver::*;
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_basic() {
let payments = Payments::builder()
.record(Payment::new(
Person::new("A"),
Money::new(1200),
&[Person::new("B")],
))
.record(Payment::new(
Person::new("B"),
Money::new(1200),
&[Person::new("A"), Person::new("C"), Person::new("D")],
))
.record(Payment::new(
Person::new("C"),
Money::new(1200),
&[Person::new("A"), Person::new("B"), Person::new("D")],
))
.record(Payment::new(
Person::new("D"),
Money::new(1200),
&[Person::new("B"), Person::new("C")],
))
.build();
let expected_obligations = Obligations::builder()
.record(
Obligation::builder()
.from(Person::new("C"))
.to(Person::new("D"))
.amount(Money::new(100))
.build(),
)
.record(
Obligation::builder()
.from(Person::new("B"))
.to(Person::new("D"))
.amount(Money::new(100))
.build(),
)
.record(
Obligation::builder()
.from(Person::new("B"))
.to(Person::new("C"))
.amount(Money::new(300))
.build(),
)
.build();
let obligations = payments.who_pays_whom().unwrap();
assert_eq!(expected_obligations, obligations);
}
#[test]
fn test_multiple_non_payers() {
let everyone = &[
Person::new("A"),
Person::new("B"),
Person::new("C"),
Person::new("D"),
Person::new("E"),
Person::new("F"),
Person::new("G"),
Person::new("H"),
];
let payments = Payments::builder()
.record(
Payment::builder()
.from(Person::new("A"))
.to(everyone)
.amount(Money::new(37009))
.build(),
)
.record(
Payment::builder()
.from(Person::new("B"))
.to(everyone)
.amount(Money::new(35300))
.build(),
)
.record(
Payment::builder()
.from(Person::new("C"))
.to(everyone)
.amount(Money::new(7249))
.build(),
)
.record(
Payment::builder()
.from(Person::new("D"))
.to(everyone)
.amount(Money::new(0))
.build(),
)
.record(
Payment::builder()
.from(Person::new("E"))
.to(everyone)
.amount(Money::new(0))
.build(),
)
.record(
Payment::builder()
.from(Person::new("F"))
.to(everyone)
.amount(Money::new(0))
.build(),
)
.record(
Payment::builder()
.from(Person::new("G"))
.to(everyone)
.amount(Money::new(0))
.build(),
)
.record(
Payment::builder()
.from(Person::new("H"))
.to(everyone)
.amount(Money::new(0))
.build(),
)
.build();
let expected_obligations = Obligations::builder()
.record(
Obligation::builder()
.from(Person::new("C"))
.to(Person::new("A"))
.amount(Money::new(2696))
.build(),
)
.record(
Obligation::builder()
.from(Person::new("E"))
.to(Person::new("A"))
.amount(Money::new(9944))
.build(),
)
.record(
Obligation::builder()
.from(Person::new("G"))
.to(Person::new("A"))
.amount(Money::new(9944))
.build(),
)
.record(
Obligation::builder()
.from(Person::new("D"))
.to(Person::new("B"))
.amount(Money::new(9944))
.build(),
)
.record(
Obligation::builder()
.from(Person::new("F"))
.to(Person::new("B"))
.amount(Money::new(9944))
.build(),
)
.record(
Obligation::builder()
.from(Person::new("H"))
.to(Person::new("B"))
.amount(Money::new(9944))
.build(),
)
.record(
Obligation::builder()
.from(Person::new("B"))
.to(Person::new("A"))
.amount(Money::new(4480))
.build(),
)
.build();
let obligations = payments.who_pays_whom().unwrap();
assert_eq!(expected_obligations, obligations);
}
#[test]
fn test_reduce_same_weight() {
let payments = Payments::builder()
.record(Payment::new(
Person::new("A"),
Money::new(2000),
&[Person::new("B"), Person::new("C"), Person::new("H")],
))
.record(Payment::new(
Person::new("C"),
Money::new(500),
&[Person::new("H")],
))
.record(Payment::new(
Person::new("B"),
Money::new(600),
&[Person::new("C"), Person::new("H")],
))
.build();
let expected_obligations = Obligations::builder()
.record(
Obligation::builder()
.from(Person::new("B"))
.to(Person::new("A"))
.amount(Money::new(100))
.build(),
)
.record(
Obligation::builder()
.from(Person::new("C"))
.to(Person::new("A"))
.amount(Money::new(450))
.build(),
)
.record(
Obligation::builder()
.from(Person::new("H"))
.to(Person::new("A"))
.amount(Money::new(950))
.build(),
)
.build();
let obligations = payments.who_pays_whom().unwrap();
assert_eq!(expected_obligations, obligations);
}
}