From 1b6a04ca5504955c571d1c97504fb45ea0befee4 Mon Sep 17 00:00:00 2001 From: Valentin Popov Date: Mon, 8 Jan 2024 01:21:28 +0400 Subject: Initial vendor packages Signed-off-by: Valentin Popov --- vendor/serde/src/de/size_hint.rs | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) create mode 100644 vendor/serde/src/de/size_hint.rs (limited to 'vendor/serde/src/de/size_hint.rs') diff --git a/vendor/serde/src/de/size_hint.rs b/vendor/serde/src/de/size_hint.rs new file mode 100644 index 0000000..4a4fe25 --- /dev/null +++ b/vendor/serde/src/de/size_hint.rs @@ -0,0 +1,29 @@ +use crate::lib::*; + +pub fn from_bounds(iter: &I) -> Option +where + I: Iterator, +{ + helper(iter.size_hint()) +} + +#[cfg(any(feature = "std", feature = "alloc"))] +pub fn cautious(hint: Option) -> usize { + const MAX_PREALLOC_BYTES: usize = 1024 * 1024; + + if mem::size_of::() == 0 { + 0 + } else { + cmp::min( + hint.unwrap_or(0), + MAX_PREALLOC_BYTES / mem::size_of::(), + ) + } +} + +fn helper(bounds: (usize, Option)) -> Option { + match bounds { + (lower, Some(upper)) if lower == upper => Some(upper), + _ => None, + } +} -- cgit v1.2.3