- Motion and delete commands read rows through RowsView (on-demand,
version-cached) instead of Buffer::Rows(), which rebuilt every line of
the file after each edit. On a 500k-line buffer after an edit:
backspace/delete/motions 80-90 ms -> ~0.1 ms; C-u 3000 C-d 273 s ->
0.25 s. Whole-buffer search scans keep Rows() (cached between edits).
- While a prompt is open only prompt-aware and view-only commands run.
Others edited the buffer behind the prompt (bypassing the read-only
check) or switched/closed buffers under a pending confirmation, which
then acted on the wrong buffer. The ':' command path now applies the
read-only check too.
- Pasting into a prompt (ImGui) flattens line breaks to spaces instead
of emitting Newline, which accepted the prompt and sent the rest of
the paste to the buffer (or ran replace-all).
- The mark region clamps both ends; a stale mark past the end of the
buffer is treated as end of buffer. This fixes kill-region deleting
the wrong text and leaving the cursor past end-of-line.
- Kill-line with a count stops at end of buffer instead of killing
lines above the cursor (regression from the D3 change).
- Undo groups nest, so SmartNewline in visual-line mode is one step.
- Word motions and word deletion treat non-ASCII bytes as word
characters and so never split a UTF-8 character.
- The universal-argument count saturates at 1,000,000 instead of
overflowing int.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015rcVQiiWyTzoNrsvLSaAfB