ZIm/zed/src/test.rs
2021-03-18 13:13:31 -06:00

99 lines
2.8 KiB
Rust

use rand::Rng;
use std::collections::BTreeMap;
use crate::time::ReplicaId;
#[derive(Clone)]
struct Envelope<T: Clone> {
message: T,
sender: ReplicaId,
}
pub(crate) struct Network<T: Clone> {
inboxes: BTreeMap<ReplicaId, Vec<Envelope<T>>>,
all_messages: Vec<T>,
}
impl<T: Clone> Network<T> {
pub fn new() -> Self {
Network {
inboxes: BTreeMap::new(),
all_messages: Vec::new(),
}
}
pub fn add_peer(&mut self, id: ReplicaId) {
self.inboxes.insert(id, Vec::new());
}
pub fn is_idle(&self) -> bool {
self.inboxes.values().all(|i| i.is_empty())
}
pub fn broadcast<R>(&mut self, sender: ReplicaId, messages: Vec<T>, rng: &mut R)
where
R: Rng,
{
for (replica, inbox) in self.inboxes.iter_mut() {
if *replica != sender {
for message in &messages {
let min_index = inbox
.iter()
.enumerate()
.rev()
.find_map(|(index, envelope)| {
if sender == envelope.sender {
Some(index + 1)
} else {
None
}
})
.unwrap_or(0);
// Insert one or more duplicates of this message *after* the previous
// message delivered by this replica.
for _ in 0..rng.gen_range(1, 4) {
let insertion_index = rng.gen_range(min_index, inbox.len() + 1);
inbox.insert(
insertion_index,
Envelope {
message: message.clone(),
sender,
},
);
}
}
}
}
self.all_messages.extend(messages);
}
pub fn has_unreceived(&self, receiver: ReplicaId) -> bool {
!self.inboxes[&receiver].is_empty()
}
pub fn receive<R>(&mut self, receiver: ReplicaId, rng: &mut R) -> Vec<T>
where
R: Rng,
{
let inbox = self.inboxes.get_mut(&receiver).unwrap();
let count = rng.gen_range(0, inbox.len() + 1);
inbox
.drain(0..count)
.map(|envelope| envelope.message)
.collect()
}
}
pub fn sample_text(rows: usize, cols: usize) -> String {
let mut text = String::new();
for row in 0..rows {
let c: char = ('a' as u32 + row as u32) as u8 as char;
let mut line = c.to_string().repeat(cols);
if row < rows - 1 {
line.push('\n');
}
text += &line;
}
text
}