get: panics if the range includes usize::MAX

Philippe-Cholet · jswrenn · commit 4dd6ba0e7c44 · 2024-05-14T14:09:02.000Z
diff --git a/src/iter_index.rs b/src/iter_index.rs
@@ -48,11 +48,11 @@ impl<I> IteratorIndex<I> for RangeInclusive<usize>
 where
     I: Iterator,
 {
-    type Output = Take<Skip<I>>;
+    type Output = Skip<Take<I>>;
 
     fn index(self, iter: I) -> Self::Output {
-        iter.skip(*self.start())
-            .take((1 + *self.end()).saturating_sub(*self.start()))
+        assert_ne!(*self.end(), usize::MAX);
+        iter.take(self.end() + 1).skip(*self.start())
     }
 }
 
@@ -74,6 +74,7 @@ where
     type Output = Take<I>;
 
     fn index(self, iter: I) -> Self::Output {
+        assert_ne!(self.end, usize::MAX);
         iter.take(self.end + 1)
     }
 }
diff --git a/src/lib.rs b/src/lib.rs
@@ -511,6 +511,8 @@ pub trait Itertools: Iterator {
     ///
     /// Works similarly to [`slice::get`](https://doc.rust-lang.org/std/primitive.slice.html#method.get).
     ///
+    /// **Panics** if the range includes `usize::MAX`.
+    ///
     /// It's a generalisation of [`Iterator::take`] and [`Iterator::skip`],
     /// and uses these under the hood.
     /// Therefore, the resulting iterator is [`DoubleEndedIterator`]

Original file line number	Diff line number	Diff line change
`@@ -48,11 +48,11 @@ impl<I> IteratorIndex<I> for RangeInclusive<usize>`
`48`	`48`	`where`
`49`	`49`	`I: Iterator,`
`50`	`50`	`{`
`51`		`- type Output = Take<Skip<I>>;`
	`51`	`+ type Output = Skip<Take<I>>;`
`52`	`52`
`53`	`53`	`fn index(self, iter: I) -> Self::Output {`
`54`		`- iter.skip(*self.start())`
`55`		`- .take((1 + self.end()).saturating_sub(self.start()))`
	`54`	`+ assert_ne!(*self.end(), usize::MAX);`
	`55`	`+ iter.take(self.end() + 1).skip(*self.start())`
`56`	`56`	`}`
`57`	`57`	`}`
`58`	`58`
`@@ -74,6 +74,7 @@ where`
`74`	`74`	`type Output = Take<I>;`
`75`	`75`
`76`	`76`	`fn index(self, iter: I) -> Self::Output {`
	`77`	`+ assert_ne!(self.end, usize::MAX);`
`77`	`78`	`iter.take(self.end + 1)`
`78`	`79`	`}`
`79`	`80`	`}`