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use std::convert::From;
use std::fmt::{Display, Formatter, Result};
use std::sync::{Arc, Mutex};
#[derive(Clone)]
pub struct Snap(Arc<Mutex<String>>);
impl Snap {
#[allow(clippy::new_without_default)]
pub fn new() -> Self {
Self(Arc::new(Mutex::new(String::new())))
}
pub fn from<S: Into<String>>(s: S) -> Self {
Self(Arc::new(Mutex::new(s.into())))
}
pub fn push<S: Into<String>>(&self, s: S) {
let mut content = self.0.lock().unwrap();
let s = s.into();
content.push_str(&s);
}
pub fn pushln<S: Into<String>>(&self, s: S) {
self.push(s);
self.push("\n");
}
}
impl From<&Snap> for String {
fn from(snap: &Snap) -> Self {
snap.0.lock().unwrap().clone()
}
}
impl Display for Snap {
fn fmt(&self, f: &mut Formatter<'_>) -> Result {
write!(f, "{}", self.0.lock().unwrap())
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn snap() {
let snap = Snap::from("\n");
let closure_captured_snap_by_ref = || {
snap.pushln("new line");
};
closure_captured_snap_by_ref();
closure_captured_snap_by_ref();
closure_captured_snap_by_ref();
crate::assert_equal!(
snap.to_string(),
"
new line
new line
new line
"
.to_string()
);
}
}