Typing over a selection composed two edits in Lua —
delete_region() + insert_char() — so it recorded two undo steps:
one undo left the half-replaced text, two restored the original.
Undo granularity is per apply_edit in both modes (v0.1 pushes one
UndoEntry per edit; CRDT commits per edit via export and groups by
commit, with record_checkpoint unused), so the fix is to make
type-over one edit.
New core EditorCore::insert_char_over_region emits a single
EditOp::Replace when a region is active (cursor past the inserted
bytes, selection cleared) and delegates to insert_char otherwise.
The three type-over commands (buffer.newline / tab / self-insert)
call it via a new Lua binding instead of the delete+insert pair.
delete_region and insert_char are unchanged for their other
callers; region-aware backspace/delete already emit one op.
Verified one undo unit in BOTH modes (dual_mode
replace_is_a_single_undo_step covers v01 + crdt — a CRDT Replace is
delete-then-insert internally but one commit) plus an end-to-end
acceptance test through the key-dispatch path.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
- S-<arrows>/S-<home>/S-<end> (+C-S word/paragraph variants) extend a
selection; the TUI grid paints it reverse-video; double-click
selects the word at point.
- Backspace / Delete consume the active region (delete_region first,
falling back to single-codepoint semantics).
- Typing replaces the region: buffer.self-insert / newline / tab
delete_region before inserting. pmacs-gpu cooperates by
round-tripping keys while an own-window selection is active, so
the region-aware commands run instead of a raw optimistic op.
- tests/cua_region_acceptance.rs drives the real dispatch path:
select -> BS/DEL/char/Enter, plus the no-region fallbacks.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Land the Model Context Protocol (MCP) integration as a transport binding,
not a built-in feature. Six Lua functions plus userdata methods expose
the substance of three MCP feature areas (resources, tools, prompts), a
notification dispatcher, and a non-trivial AI-assistance example package
that meets the architectural ship gate (spec/pmacs-spec.tex:1572): zero
direct calls into the Rust core, zero special-cased MCP handling outside
the public API, source under 2000 lines of Lua.
The M9.5 -> M9.6 -> M9.7 -> M9.8 layered composition validates the claim
"AI is a transport binding, not a feature" -- pmacs-mcp-ai composes with
pmacs-mcp-prompts.render and inherits notification handling transitively
through M9.7's package, demonstrating that the AI domain is a layer
above MCP, not a thread woven through the core.
Subtask shape:
M9.1 stdio transport + initialize handshake + restart policy
M9.2 resources with in-flight + settled cache and per-uri invalidation
M9.3 tools with isError-vs-JSON-RPC-error semantics + cancellation
M9.4 prompts with required-argument validation
M9.5 notification dispatcher (on_notification, off_notification)
M9.6 tools-as-commands fixture package + 12 audit findings disposed
M9.7 prompts-as-result-buffers fixture package + tree-sitter-md grammar
M9.8 AI-assistance fixture package (363+ LoC; 17/17 acceptance tests)
M9.9 formal package audit -- PASS on all three criteria
M9.10 release: TRANSITION-M9.md + MCP-for-package-authors guide
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>