diff options
Diffstat (limited to 'vendor/syn/tests/test_iterators.rs')
-rw-r--r-- | vendor/syn/tests/test_iterators.rs | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/vendor/syn/tests/test_iterators.rs b/vendor/syn/tests/test_iterators.rs new file mode 100644 index 0000000..5f0eff5 --- /dev/null +++ b/vendor/syn/tests/test_iterators.rs @@ -0,0 +1,70 @@ +#![allow(clippy::uninlined_format_args)] + +use syn::punctuated::{Pair, Punctuated}; +use syn::Token; + +#[macro_use] +mod macros; + +macro_rules! check_exact_size_iterator { + ($iter:expr) => {{ + let iter = $iter; + let size_hint = iter.size_hint(); + let len = iter.len(); + let count = iter.count(); + assert_eq!(len, count); + assert_eq!(size_hint, (count, Some(count))); + }}; +} + +#[test] +fn pairs() { + let mut p: Punctuated<_, Token![,]> = punctuated!(2, 3, 4); + + check_exact_size_iterator!(p.pairs()); + check_exact_size_iterator!(p.pairs_mut()); + check_exact_size_iterator!(p.into_pairs()); + + let mut p: Punctuated<_, Token![,]> = punctuated!(2, 3, 4); + + assert_eq!(p.pairs().next_back().map(Pair::into_value), Some(&4)); + assert_eq!( + p.pairs_mut().next_back().map(Pair::into_value), + Some(&mut 4) + ); + assert_eq!(p.into_pairs().next_back().map(Pair::into_value), Some(4)); +} + +#[test] +fn iter() { + let mut p: Punctuated<_, Token![,]> = punctuated!(2, 3, 4); + + check_exact_size_iterator!(p.iter()); + check_exact_size_iterator!(p.iter_mut()); + check_exact_size_iterator!(p.into_iter()); + + let mut p: Punctuated<_, Token![,]> = punctuated!(2, 3, 4); + + assert_eq!(p.iter().next_back(), Some(&4)); + assert_eq!(p.iter_mut().next_back(), Some(&mut 4)); + assert_eq!(p.into_iter().next_back(), Some(4)); +} + +#[test] +fn may_dangle() { + let p: Punctuated<_, Token![,]> = punctuated!(2, 3, 4); + for element in &p { + if *element == 2 { + drop(p); + break; + } + } + + let mut p: Punctuated<_, Token![,]> = punctuated!(2, 3, 4); + for element in &mut p { + if *element == 2 { + drop(p); + break; + } + } +} |