1 // Check that we are flagged for ignoring `must_use` parallel adaptors.
2 // (unfortunately there's no error code for `unused_must_use`)
3 
4 macro_rules! must_use {
5     ($( $name:ident #[$expr:meta] )*) => {$(
6         /// First sanity check that the expression is OK.
7         ///
8         /// ```
9         /// #![deny(unused_must_use)]
10         ///
11         /// use rayon::prelude::*;
12         ///
13         /// let v: Vec<_> = (0..100).map(Some).collect();
14         /// let _ =
15         #[$expr]
16         /// ```
17         ///
18         /// Now trigger the `must_use`.
19         ///
20         /// ```compile_fail
21         /// #![deny(unused_must_use)]
22         ///
23         /// use rayon::prelude::*;
24         ///
25         /// let v: Vec<_> = (0..100).map(Some).collect();
26         #[$expr]
27         /// ```
28         mod $name {}
29     )*}
30 }
31 
32 must_use! {
33     chain               /** v.par_iter().chain(&v); */
34     chunks              /** v.par_iter().chunks(2); */
35     cloned              /** v.par_iter().cloned(); */
36     copied              /** v.par_iter().copied(); */
37     enumerate           /** v.par_iter().enumerate(); */
38     filter              /** v.par_iter().filter(|_| true); */
39     filter_map          /** v.par_iter().filter_map(|x| *x); */
40     flat_map            /** v.par_iter().flat_map(|x| *x); */
41     flatten             /** v.par_iter().flatten(); */
42     fold                /** v.par_iter().fold(|| 0, |x, _| x); */
43     fold_with           /** v.par_iter().fold_with(0, |x, _| x); */
44     try_fold            /** v.par_iter().try_fold(|| 0, |x, _| Some(x)); */
45     try_fold_with       /** v.par_iter().try_fold_with(0, |x, _| Some(x)); */
46     inspect             /** v.par_iter().inspect(|_| {}); */
47     interleave          /** v.par_iter().interleave(&v); */
48     interleave_shortest /** v.par_iter().interleave_shortest(&v); */
49     intersperse         /** v.par_iter().intersperse(&None); */
50     map                 /** v.par_iter().map(|x| x); */
51     map_with            /** v.par_iter().map_with(0, |_, x| x); */
52     map_init            /** v.par_iter().map_init(|| 0, |_, x| x); */
53     panic_fuse          /** v.par_iter().panic_fuse(); */
54     rev                 /** v.par_iter().rev(); */
55     skip                /** v.par_iter().skip(1); */
56     take                /** v.par_iter().take(1); */
57     update              /** v.par_iter().update(|_| {}); */
58     while_some          /** v.par_iter().cloned().while_some(); */
59     with_max_len        /** v.par_iter().with_max_len(1); */
60     with_min_len        /** v.par_iter().with_min_len(1); */
61     zip                 /** v.par_iter().zip(&v); */
62     zip_eq              /** v.par_iter().zip_eq(&v); */
63 }
64