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-rw-r--r--vendor/rayon/src/iter/find_first_last/test.rs106
1 files changed, 106 insertions, 0 deletions
diff --git a/vendor/rayon/src/iter/find_first_last/test.rs b/vendor/rayon/src/iter/find_first_last/test.rs
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+use super::*;
+use std::sync::atomic::AtomicUsize;
+
+#[test]
+fn same_range_first_consumers_return_correct_answer() {
+ let find_op = |x: &i32| x % 2 == 0;
+ let first_found = AtomicUsize::new(usize::max_value());
+ let far_right_consumer = FindConsumer::new(&find_op, MatchPosition::Leftmost, &first_found);
+
+ // We save a consumer that will be far to the right of the main consumer (and therefore not
+ // sharing an index range with that consumer) for fullness testing
+ let consumer = far_right_consumer.split_off_left();
+
+ // split until we have an indivisible range
+ let bits_in_usize = usize::min_value().count_zeros();
+
+ for _ in 0..bits_in_usize {
+ consumer.split_off_left();
+ }
+
+ let reducer = consumer.to_reducer();
+ // the left and right folders should now have the same range, having
+ // exhausted the resolution of usize
+ let left_folder = consumer.split_off_left().into_folder();
+ let right_folder = consumer.into_folder();
+
+ let left_folder = left_folder.consume(0).consume(1);
+ assert_eq!(left_folder.boundary, right_folder.boundary);
+ // expect not full even though a better match has been found because the
+ // ranges are the same
+ assert!(!right_folder.full());
+ assert!(far_right_consumer.full());
+ let right_folder = right_folder.consume(2).consume(3);
+ assert_eq!(
+ reducer.reduce(left_folder.complete(), right_folder.complete()),
+ Some(0)
+ );
+}
+
+#[test]
+fn same_range_last_consumers_return_correct_answer() {
+ let find_op = |x: &i32| x % 2 == 0;
+ let last_found = AtomicUsize::new(0);
+ let consumer = FindConsumer::new(&find_op, MatchPosition::Rightmost, &last_found);
+
+ // We save a consumer that will be far to the left of the main consumer (and therefore not
+ // sharing an index range with that consumer) for fullness testing
+ let far_left_consumer = consumer.split_off_left();
+
+ // split until we have an indivisible range
+ let bits_in_usize = usize::min_value().count_zeros();
+ for _ in 0..bits_in_usize {
+ consumer.split_off_left();
+ }
+
+ let reducer = consumer.to_reducer();
+ // due to the exact calculation in split_off_left, the very last consumer has a
+ // range of width 2, so we use the second-to-last consumer instead to get
+ // the same boundary on both folders
+ let consumer = consumer.split_off_left();
+ let left_folder = consumer.split_off_left().into_folder();
+ let right_folder = consumer.into_folder();
+ let right_folder = right_folder.consume(2).consume(3);
+ assert_eq!(left_folder.boundary, right_folder.boundary);
+ // expect not full even though a better match has been found because the
+ // ranges are the same
+ assert!(!left_folder.full());
+ assert!(far_left_consumer.full());
+ let left_folder = left_folder.consume(0).consume(1);
+ assert_eq!(
+ reducer.reduce(left_folder.complete(), right_folder.complete()),
+ Some(2)
+ );
+}
+
+// These tests requires that a folder be assigned to an iterator with more than
+// one element. We can't necessarily determine when that will happen for a given
+// input to find_first/find_last, so we test the folder directly here instead.
+#[test]
+fn find_first_folder_does_not_clobber_first_found() {
+ let best_found = AtomicUsize::new(usize::max_value());
+ let f = FindFolder {
+ find_op: &(|&_: &i32| -> bool { true }),
+ boundary: 0,
+ match_position: MatchPosition::Leftmost,
+ best_found: &best_found,
+ item: None,
+ };
+ let f = f.consume(0_i32).consume(1_i32).consume(2_i32);
+ assert!(f.full());
+ assert_eq!(f.complete(), Some(0_i32));
+}
+
+#[test]
+fn find_last_folder_yields_last_match() {
+ let best_found = AtomicUsize::new(0);
+ let f = FindFolder {
+ find_op: &(|&_: &i32| -> bool { true }),
+ boundary: 0,
+ match_position: MatchPosition::Rightmost,
+ best_found: &best_found,
+ item: None,
+ };
+ let f = f.consume(0_i32).consume(1_i32).consume(2_i32);
+ assert_eq!(f.complete(), Some(2_i32));
+}