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#![cfg(test)]
#![allow(unused_assignments)]
// These tests are primarily targeting "abusive" producers that will
// try to drive the "collect consumer" incorrectly. These should
// result in panics.
use super::collect_with_consumer;
use crate::iter::plumbing::*;
use rayon_core::join;
use std::fmt;
use std::panic;
use std::sync::atomic::{AtomicUsize, Ordering};
use std::thread::Result as ThreadResult;
/// Promises to produce 2 items, but then produces 3. Does not do any
/// splits at all.
#[test]
#[should_panic(expected = "too many values")]
fn produce_too_many_items() {
let mut v = vec![];
collect_with_consumer(&mut v, 2, |consumer| {
let mut folder = consumer.into_folder();
folder = folder.consume(22);
folder = folder.consume(23);
folder = folder.consume(24);
unreachable!("folder does not complete")
});
}
/// Produces fewer items than promised. Does not do any
/// splits at all.
#[test]
#[should_panic(expected = "expected 5 total writes, but got 2")]
fn produce_fewer_items() {
let mut v = vec![];
collect_with_consumer(&mut v, 5, |consumer| {
let mut folder = consumer.into_folder();
folder = folder.consume(22);
folder = folder.consume(23);
folder.complete()
});
}
// Complete is not called by the consumer. Hence,the collection vector is not fully initialized.
#[test]
#[should_panic(expected = "expected 4 total writes, but got 2")]
fn left_produces_items_with_no_complete() {
let mut v = vec![];
collect_with_consumer(&mut v, 4, |consumer| {
let (left_consumer, right_consumer, _) = consumer.split_at(2);
let mut left_folder = left_consumer.into_folder();
let mut right_folder = right_consumer.into_folder();
left_folder = left_folder.consume(0).consume(1);
right_folder = right_folder.consume(2).consume(3);
right_folder.complete()
});
}
// Complete is not called by the right consumer. Hence,the
// collection vector is not fully initialized.
#[test]
#[should_panic(expected = "expected 4 total writes, but got 2")]
fn right_produces_items_with_no_complete() {
let mut v = vec![];
collect_with_consumer(&mut v, 4, |consumer| {
let (left_consumer, right_consumer, _) = consumer.split_at(2);
let mut left_folder = left_consumer.into_folder();
let mut right_folder = right_consumer.into_folder();
left_folder = left_folder.consume(0).consume(1);
right_folder = right_folder.consume(2).consume(3);
left_folder.complete()
});
}
// Complete is not called by the consumer. Hence,the collection vector is not fully initialized.
#[test]
#[cfg_attr(not(panic = "unwind"), ignore)]
fn produces_items_with_no_complete() {
let counter = DropCounter::default();
let mut v = vec![];
let panic_result = panic::catch_unwind(panic::AssertUnwindSafe(|| {
collect_with_consumer(&mut v, 2, |consumer| {
let mut folder = consumer.into_folder();
folder = folder.consume(counter.element());
folder = folder.consume(counter.element());
panic!("folder does not complete");
});
}));
assert!(v.is_empty());
assert_is_panic_with_message(&panic_result, "folder does not complete");
counter.assert_drop_count();
}
// The left consumer produces too many items while the right
// consumer produces correct number.
#[test]
#[should_panic(expected = "too many values")]
fn left_produces_too_many_items() {
let mut v = vec![];
collect_with_consumer(&mut v, 4, |consumer| {
let (left_consumer, right_consumer, _) = consumer.split_at(2);
let mut left_folder = left_consumer.into_folder();
let mut right_folder = right_consumer.into_folder();
left_folder = left_folder.consume(0).consume(1).consume(2);
right_folder = right_folder.consume(2).consume(3);
let _ = right_folder.complete();
unreachable!("folder does not complete");
});
}
// The right consumer produces too many items while the left
// consumer produces correct number.
#[test]
#[should_panic(expected = "too many values")]
fn right_produces_too_many_items() {
let mut v = vec![];
collect_with_consumer(&mut v, 4, |consumer| {
let (left_consumer, right_consumer, _) = consumer.split_at(2);
let mut left_folder = left_consumer.into_folder();
let mut right_folder = right_consumer.into_folder();
left_folder = left_folder.consume(0).consume(1);
right_folder = right_folder.consume(2).consume(3).consume(4);
let _ = left_folder.complete();
unreachable!("folder does not complete");
});
}
// The left consumer produces fewer items while the right
// consumer produces correct number.
#[test]
#[should_panic(expected = "expected 4 total writes, but got 1")]
fn left_produces_fewer_items() {
let mut v = vec![];
collect_with_consumer(&mut v, 4, |consumer| {
let reducer = consumer.to_reducer();
let (left_consumer, right_consumer, _) = consumer.split_at(2);
let mut left_folder = left_consumer.into_folder();
let mut right_folder = right_consumer.into_folder();
left_folder = left_folder.consume(0);
right_folder = right_folder.consume(2).consume(3);
let left_result = left_folder.complete();
let right_result = right_folder.complete();
reducer.reduce(left_result, right_result)
});
}
// The left and right consumer produce the correct number but
// only left result is returned
#[test]
#[should_panic(expected = "expected 4 total writes, but got 2")]
fn only_left_result() {
let mut v = vec![];
collect_with_consumer(&mut v, 4, |consumer| {
let (left_consumer, right_consumer, _) = consumer.split_at(2);
let mut left_folder = left_consumer.into_folder();
let mut right_folder = right_consumer.into_folder();
left_folder = left_folder.consume(0).consume(1);
right_folder = right_folder.consume(2).consume(3);
let left_result = left_folder.complete();
let _ = right_folder.complete();
left_result
});
}
// The left and right consumer produce the correct number but
// only right result is returned
#[test]
#[should_panic(expected = "expected 4 total writes, but got 2")]
fn only_right_result() {
let mut v = vec![];
collect_with_consumer(&mut v, 4, |consumer| {
let (left_consumer, right_consumer, _) = consumer.split_at(2);
let mut left_folder = left_consumer.into_folder();
let mut right_folder = right_consumer.into_folder();
left_folder = left_folder.consume(0).consume(1);
right_folder = right_folder.consume(2).consume(3);
let _ = left_folder.complete();
right_folder.complete()
});
}
// The left and right consumer produce the correct number but reduce
// in the wrong order.
#[test]
#[should_panic(expected = "expected 4 total writes, but got 2")]
fn reducer_does_not_preserve_order() {
let mut v = vec![];
collect_with_consumer(&mut v, 4, |consumer| {
let reducer = consumer.to_reducer();
let (left_consumer, right_consumer, _) = consumer.split_at(2);
let mut left_folder = left_consumer.into_folder();
let mut right_folder = right_consumer.into_folder();
left_folder = left_folder.consume(0).consume(1);
right_folder = right_folder.consume(2).consume(3);
let left_result = left_folder.complete();
let right_result = right_folder.complete();
reducer.reduce(right_result, left_result)
});
}
// The right consumer produces fewer items while the left
// consumer produces correct number.
#[test]
#[should_panic(expected = "expected 4 total writes, but got 3")]
fn right_produces_fewer_items() {
let mut v = vec![];
collect_with_consumer(&mut v, 4, |consumer| {
let reducer = consumer.to_reducer();
let (left_consumer, right_consumer, _) = consumer.split_at(2);
let mut left_folder = left_consumer.into_folder();
let mut right_folder = right_consumer.into_folder();
left_folder = left_folder.consume(0).consume(1);
right_folder = right_folder.consume(2);
let left_result = left_folder.complete();
let right_result = right_folder.complete();
reducer.reduce(left_result, right_result)
});
}
// The left consumer panics and the right stops short, like `panic_fuse()`.
// We should get the left panic without finishing `collect_with_consumer`.
#[test]
#[should_panic(expected = "left consumer panic")]
fn left_panics() {
let mut v = vec![];
collect_with_consumer(&mut v, 4, |consumer| {
let reducer = consumer.to_reducer();
let (left_consumer, right_consumer, _) = consumer.split_at(2);
let (left_result, right_result) = join(
|| {
let mut left_folder = left_consumer.into_folder();
left_folder = left_folder.consume(0);
panic!("left consumer panic");
},
|| {
let mut right_folder = right_consumer.into_folder();
right_folder = right_folder.consume(2);
right_folder.complete() // early return
},
);
reducer.reduce(left_result, right_result)
});
unreachable!();
}
// The right consumer panics and the left stops short, like `panic_fuse()`.
// We should get the right panic without finishing `collect_with_consumer`.
#[test]
#[should_panic(expected = "right consumer panic")]
fn right_panics() {
let mut v = vec![];
collect_with_consumer(&mut v, 4, |consumer| {
let reducer = consumer.to_reducer();
let (left_consumer, right_consumer, _) = consumer.split_at(2);
let (left_result, right_result) = join(
|| {
let mut left_folder = left_consumer.into_folder();
left_folder = left_folder.consume(0);
left_folder.complete() // early return
},
|| {
let mut right_folder = right_consumer.into_folder();
right_folder = right_folder.consume(2);
panic!("right consumer panic");
},
);
reducer.reduce(left_result, right_result)
});
unreachable!();
}
// The left consumer produces fewer items while the right
// consumer produces correct number; check that created elements are dropped
#[test]
#[cfg_attr(not(panic = "unwind"), ignore)]
fn left_produces_fewer_items_drops() {
let counter = DropCounter::default();
let mut v = vec![];
let panic_result = panic::catch_unwind(panic::AssertUnwindSafe(|| {
collect_with_consumer(&mut v, 4, |consumer| {
let reducer = consumer.to_reducer();
let (left_consumer, right_consumer, _) = consumer.split_at(2);
let mut left_folder = left_consumer.into_folder();
let mut right_folder = right_consumer.into_folder();
left_folder = left_folder.consume(counter.element());
right_folder = right_folder
.consume(counter.element())
.consume(counter.element());
let left_result = left_folder.complete();
let right_result = right_folder.complete();
reducer.reduce(left_result, right_result)
});
}));
assert!(v.is_empty());
assert_is_panic_with_message(&panic_result, "expected 4 total writes, but got 1");
counter.assert_drop_count();
}
/// This counter can create elements, and then count and verify
/// the number of which have actually been dropped again.
#[derive(Default)]
struct DropCounter {
created: AtomicUsize,
dropped: AtomicUsize,
}
struct Element<'a>(&'a AtomicUsize);
impl DropCounter {
fn created(&self) -> usize {
self.created.load(Ordering::SeqCst)
}
fn dropped(&self) -> usize {
self.dropped.load(Ordering::SeqCst)
}
fn element(&self) -> Element<'_> {
self.created.fetch_add(1, Ordering::SeqCst);
Element(&self.dropped)
}
fn assert_drop_count(&self) {
assert_eq!(
self.created(),
self.dropped(),
"Expected {} dropped elements, but found {}",
self.created(),
self.dropped()
);
}
}
impl<'a> Drop for Element<'a> {
fn drop(&mut self) {
self.0.fetch_add(1, Ordering::SeqCst);
}
}
/// Assert that the result from catch_unwind is a panic that contains expected message
fn assert_is_panic_with_message<T>(result: &ThreadResult<T>, expected: &str)
where
T: fmt::Debug,
{
match result {
Ok(value) => {
panic!(
"assertion failure: Expected panic, got successful {:?}",
value
);
}
Err(error) => {
let message_str = error.downcast_ref::<&'static str>().cloned();
let message_string = error.downcast_ref::<String>().map(String::as_str);
if let Some(message) = message_str.or(message_string) {
if !message.contains(expected) {
panic!(
"assertion failure: Expected {:?}, but found panic with {:?}",
expected, message
);
}
// assertion passes
} else {
panic!(
"assertion failure: Expected {:?}, but found panic with unknown value",
expected
);
}
}
}
}