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use crate::core::{Join, Matcher};
pub struct BeEmpty;
pub fn be_empty() -> BeEmpty {
BeEmpty
}
impl<A, T> Matcher<A, ()> for BeEmpty
where
A: Iterator<Item = T> + Clone,
{
fn failure_message(&self, join: Join, actual: &A) -> String {
if join.is_assertion() {
let count = actual.clone().count();
format!("expected {} be empty, got the length of {}", join, count)
} else {
format!("expected {} be empty", join)
}
}
fn matches(&self, actual: &A) -> bool {
actual.clone().count() == 0
}
}
#[cfg(test)]
mod tests {
use super::be_empty;
use crate::core::expect;
#[test]
fn be_empty_str_failure_message() {
expect("hello".chars())
.to(be_empty())
.assert_eq_message("expected to be empty, got the length of 5");
}
#[test]
fn to_not_be_empty_str_failure_message() {
expect("".chars())
.to_not(be_empty())
.assert_eq_message("expected to not be empty");
}
}