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authormo khan <mo@mokhan.ca>2025-07-02 18:36:06 -0600
committermo khan <mo@mokhan.ca>2025-07-02 18:36:06 -0600
commit8cdfa445d6629ffef4cb84967ff7017654045bc2 (patch)
tree22f0b0907c024c78d26a731e2e1f5219407d8102 /vendor/nonempty/src/nonzero.rs
parent4351c74c7c5f97156bc94d3a8549b9940ac80e3f (diff)
chore: add vendor directory
Diffstat (limited to 'vendor/nonempty/src/nonzero.rs')
-rw-r--r--vendor/nonempty/src/nonzero.rs96
1 files changed, 96 insertions, 0 deletions
diff --git a/vendor/nonempty/src/nonzero.rs b/vendor/nonempty/src/nonzero.rs
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+++ b/vendor/nonempty/src/nonzero.rs
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+#[cfg(feature = "arbitrary")]
+use arbitrary::Arbitrary;
+use std::num::NonZeroUsize;
+
+/// A non-empty list which statically guarantees certain operations
+/// cannot return zero, using [`std::num::NonZeroUsize`].
+///
+/// *Experimental*
+///
+#[repr(transparent)]
+#[cfg_attr(feature = "arbitrary", derive(Arbitrary))]
+#[derive(Clone, Debug, PartialEq, Eq, Hash, PartialOrd, Ord)]
+pub struct NonEmpty<T>(super::NonEmpty<T>);
+
+impl<T> NonEmpty<T> {
+ /// Get the length of the list.
+ pub fn len(&self) -> NonZeroUsize {
+ unsafe { NonZeroUsize::new_unchecked(self.0.tail.len() + 1) }
+ }
+
+ /// Get the capacity of the list.
+ pub fn capacity(&self) -> NonZeroUsize {
+ unsafe { NonZeroUsize::new_unchecked(self.0.tail.capacity() + 1) }
+ }
+
+ /// Truncate the list to a certain size.
+ pub fn truncate(&mut self, len: NonZeroUsize) {
+ self.tail.truncate(usize::from(len) - 1);
+ }
+}
+
+impl<T> From<super::NonEmpty<T>> for NonEmpty<T> {
+ fn from(other: super::NonEmpty<T>) -> NonEmpty<T> {
+ NonEmpty(other)
+ }
+}
+
+impl<T> std::ops::Deref for NonEmpty<T> {
+ type Target = super::NonEmpty<T>;
+
+ fn deref(&self) -> &Self::Target {
+ &self.0
+ }
+}
+
+impl<T> std::ops::DerefMut for NonEmpty<T> {
+ fn deref_mut(&mut self) -> &mut Self::Target {
+ &mut self.0
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ use crate::nonzero;
+ use crate::NonEmpty;
+
+ use std::convert::TryInto;
+
+ #[test]
+ fn test_nonzero() {
+ let nonempty: nonzero::NonEmpty<_> = NonEmpty::from((0, vec![1, 2, 3])).into();
+
+ assert_eq!(nonempty.len(), 4.try_into().unwrap());
+ assert_eq!(nonempty.capacity(), 4.try_into().unwrap());
+ }
+
+ #[cfg(feature = "arbitrary")]
+ mod arbitrary {
+ use crate::nonzero;
+ use arbitrary::{Arbitrary, Unstructured};
+
+ use std::convert::TryInto;
+
+ #[test]
+ fn test_nonzero_arbitrary_empty_tail() -> arbitrary::Result<()> {
+ let mut u = Unstructured::new(&[1, 2, 3, 4]);
+ let nonempty: nonzero::NonEmpty<_> = nonzero::NonEmpty::<i32>::arbitrary(&mut u)?;
+
+ assert_eq!(nonempty.len(), 1.try_into().unwrap());
+ assert_eq!(nonempty.capacity(), 1.try_into().unwrap());
+
+ Ok(())
+ }
+
+ #[test]
+ fn test_nonzero_arbitrary_with_tail() -> arbitrary::Result<()> {
+ let mut u = Unstructured::new(&[1, 2, 3, 4, 5, 6, 7, 8]);
+ let nonempty: nonzero::NonEmpty<_> = nonzero::NonEmpty::<i32>::arbitrary(&mut u)?;
+
+ assert_eq!(nonempty.len(), 2.try_into().unwrap());
+ assert_eq!(nonempty.capacity(), 5.try_into().unwrap());
+
+ Ok(())
+ }
+ }
+}