Implement ExactSizeIterator for DocumentIter.

src/compare/util.rs

@@ -284,13 +284,7 @@ where
     Ok(())
 }
 
-pub(crate) fn compare_children_iter<
-    'b,
-    's,
-    'x,
-    RC: 'x,
-    RI: Iterator<Item = &'x RC> + ExactSizeIterator,
->(
+pub(crate) fn compare_children_iter<'b, 's, RC, RI: Iterator<Item = RC> + ExactSizeIterator>(
     source: &'s str,
     emacs: &'b Token<'s>,
     rust_children: RI,
@@ -299,7 +293,7 @@ pub(crate) fn compare_children_iter<
     message: &mut Option<String>,
 ) -> Result<(), Box<dyn std::error::Error>>
 where
-    AstNode<'b, 's>: From<&'x RC>,
+    AstNode<'b, 's>: From<RC>,
 {
     let emacs_children = emacs.as_list()?;
     let emacs_children_length = emacs_children.len() - 2;