diff options
| -rw-r--r-- | helix-term/src/commands.rs | 70 |
1 files changed, 61 insertions, 9 deletions
diff --git a/helix-term/src/commands.rs b/helix-term/src/commands.rs index e1120ef1..e5cf7bb2 100644 --- a/helix-term/src/commands.rs +++ b/helix-term/src/commands.rs @@ -10,10 +10,11 @@ use helix_core::{ object, pos_at_coords, regex::{self, Regex, RegexBuilder}, register::Register, - search, selection, surround, textobject, LineEnding, Position, Range, Rope, RopeGraphemes, - RopeSlice, Selection, SmallVec, Tendril, Transaction, + search, selection, surround, textobject, + unicode::width::UnicodeWidthChar, + LineEnding, Position, Range, Rope, RopeGraphemes, RopeSlice, Selection, SmallVec, Tendril, + Transaction, }; - use helix_view::{ clipboard::ClipboardType, document::{Mode, SCRATCH_BUFFER_NAME}, @@ -4014,19 +4015,70 @@ pub mod insert { doc.apply(&transaction, view.id); } - // TODO: handle indent-aware delete pub fn delete_char_backward(cx: &mut Context) { let count = cx.count(); let (view, doc) = current!(cx.editor); let text = doc.text().slice(..); + let indent_unit = doc.indent_unit(); + let tab_size = doc.tab_width(); + let transaction = Transaction::change_by_selection(doc.text(), doc.selection(view.id), |range| { let pos = range.cursor(text); - ( - graphemes::nth_prev_grapheme_boundary(text, pos, count), - pos, - None, - ) + let line_start_pos = text.line_to_char(range.cursor_line(text)); + // considier to delete by indent level if all characters before `pos` are indent units. + let fragment = Cow::from(text.slice(line_start_pos..pos)); + if !fragment.is_empty() && fragment.chars().all(|ch| ch.is_whitespace()) { + if text.get_char(pos.saturating_sub(1)) == Some('\t') { + // fast path, delete one char + ( + graphemes::nth_prev_grapheme_boundary(text, pos, 1), + pos, + None, + ) + } else { + let unit_len = indent_unit.chars().count(); + // NOTE: indent_unit always contains 'only spaces' or 'only tab' according to `IndentStyle` definition. + let unit_size = if indent_unit.starts_with('\t') { + tab_size * unit_len + } else { + unit_len + }; + let width: usize = fragment + .chars() + .map(|ch| { + if ch == '\t' { + tab_size + } else { + // it can be none if it still meet control characters other than '\t' + // here just set the width to 1 (or some value better?). + ch.width().unwrap_or(1) + } + }) + .sum(); + let mut drop = width % unit_size; // round down to nearest unit + if drop == 0 { + drop = unit_size + }; // if it's already at a unit, consume a whole unit + let mut chars = fragment.chars().rev(); + let mut start = pos; + for _ in 0..drop { + // delete up to `drop` spaces + match chars.next() { + Some(' ') => start -= 1, + _ => break, + } + } + (start, pos, None) // delete! + } + } else { + // delete char + ( + graphemes::nth_prev_grapheme_boundary(text, pos, count), + pos, + None, + ) + } }); doc.apply(&transaction, view.id); } |