Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'helix-core/src/transaction.rs')
| -rw-r--r-- | helix-core/src/transaction.rs | 24 |
1 files changed, 20 insertions, 4 deletions
diff --git a/helix-core/src/transaction.rs b/helix-core/src/transaction.rs index f24f2094..c5c94b75 100644 --- a/helix-core/src/transaction.rs +++ b/helix-core/src/transaction.rs @@ -29,6 +29,12 @@ pub enum Assoc { /// Acts like `Before` if a word character is inserted /// before the position, otherwise acts like `After` BeforeWord, + /// Acts like `Before` but if the position is within an exact replacement + /// (exact size) the offset to the start of the replacement is kept + BeforeSticky, + /// Acts like `After` but if the position is within an exact replacement + /// (exact size) the offset to the start of the replacement is kept + AfterSticky, } impl Assoc { @@ -40,13 +46,17 @@ impl Assoc { fn insert_offset(self, s: &str) -> usize { let chars = s.chars().count(); match self { - Assoc::After => chars, + Assoc::After | Assoc::AfterSticky => chars, Assoc::AfterWord => s.chars().take_while(|&c| char_is_word(c)).count(), // return position before inserted text - Assoc::Before => 0, + Assoc::Before | Assoc::BeforeSticky => 0, Assoc::BeforeWord => chars - s.chars().rev().take_while(|&c| char_is_word(c)).count(), } } + + pub fn sticky(self) -> bool { + matches!(self, Assoc::BeforeSticky | Assoc::AfterSticky) + } } #[derive(Debug, Default, Clone, PartialEq, Eq)] @@ -456,8 +466,14 @@ impl ChangeSet { if pos == old_pos && assoc.stay_at_gaps() { new_pos } else { - // place to end of insert - new_pos + assoc.insert_offset(s) + let ins = assoc.insert_offset(s); + // if the deleted and inserted text have the exact same size + // keep the relative offset into the new text + if *len == ins && assoc.sticky() { + new_pos + (pos - old_pos) + } else { + new_pos + assoc.insert_offset(s) + } } }), i |