diff options
Diffstat (limited to 'helix-core')
| -rw-r--r-- | helix-core/src/history.rs | 24 |
1 files changed, 14 insertions, 10 deletions
diff --git a/helix-core/src/history.rs b/helix-core/src/history.rs index 697f29b4..5f9fa71e 100644 --- a/helix-core/src/history.rs +++ b/helix-core/src/history.rs @@ -122,17 +122,21 @@ impl History { /// Returns the changes since the given revision composed into a transaction. /// Returns None if there are no changes between the current and given revisions. pub fn changes_since(&self, revision: usize) -> Option<Transaction> { - if self.at_root() || self.current >= revision { - return None; - } + use std::cmp::Ordering::*; - // The bounds are checked in the if condition above: - // `revision` is known to be `< self.current`. - self.revisions[revision..self.current] - .iter() - .map(|revision| &revision.transaction) - .cloned() - .reduce(|acc, transaction| acc.compose(transaction)) + match revision.cmp(&self.current) { + Equal => None, + Greater => self.revisions[self.current + 1..=revision] + .iter() + .map(|revision| &revision.inversion) + .cloned() + .reduce(|acc, inversion| acc.compose(inversion)), + Less => self.revisions[revision + 1..=self.current] + .iter() + .map(|revision| &revision.transaction) + .cloned() + .reduce(|acc, transaction| acc.compose(transaction)), + } } /// Undo the last edit. |