Rebase and advanced Cherry Pick message editing

Pinned source: TortoiseGit 7338078f8ddd924b8cddee35f512f2286072136d. This connected family covers stopped message editing and the checked amendment handoff in IDD_REBASE / IDD_REBASECHERRYPICK; it does not complete either resource or the complete port.

Source behavior and native implementation

src/TortoiseProc/RebaseDlg.cpp:1488–1544 permits an edited conflict message before entering the stopped Edit phase. Existing native checked-conflict commits, conflict hint approval, message cleanup and source authorship remain in use; this batch does not replace that engine or its empty-result choices.
RebaseDlg.cpp:1565–1611 sends dirty Edit through CCommitDlg with the whole project, file checkboxes, the current message, Amend and Amend-diff-to-last semantics. Ordinary amendment repeats while tracked changes remain; explicit Split instead creates replacement parts. Native Continue now prepares that same distinction. GitRepository.beginRebaseEditSelection(expected:expectedHead:) validates the complete stopped state and HEAD, returns nil for a clean worktree, or writes a durable RebaseSplitState in amendment mode (conflictRecovery, zero accepted parts). It never resets HEAD or silently commits the whole index.
src/Git/Git.cpp:2618–2654 defines clean worktree using tracked worktree/index differences and ignores submodules; untracked/ignored files do not open the Commit dialog. The native preparation and repeated selection loop use these same working-tree/index diff gates with --ignore-submodules.
Existing CommitWindowModel.loadReplaySplit supplies the source file selection, message, author/date controls, empty-result approval and commit backend. The first accepted selection amends the applied commit with its parent topology; later selections repeat amendment while preserving excluded index/worktree changes. Explicit Split remains a separate mode. Cancelling the first dialog removes only its unstarted durable handoff; reopened zero-part handoffs resume the same amend dialog. A now-clean zero-part handoff retires before Continue. Accepted author/date choices use the existing Commit options and backend.
RebaseDlg.cpp:2520–2573 installs conflict/Edit/Squash messages, uses applied HEAD for Cherry Pick attribution and clears the undo buffer when the stopped editor changes. RebaseSessionSnapshot.messageCommit captures the actual applied HEAD together with the existing coherent stopped-state snapshot. Native Edit uses that message (including cherry picked from), presents its author/date, and resets editor identity on a phase/occurrence/applied-HEAD change. Same-phase refresh keeps the draft and undo identity. Squash uses its existing combined message and date policy, rather than substituting the applied HEAD message.
Source author/date checkboxes belong to the invoked Commit dialog; this batch does not invent competing Rebase checkboxes. The message editor refuses writes outside its existing editable phase/ownership gates. Stale form bindings cannot write a later occurrence. The existing source options, message preparation, conflict-hint approval and empty-result Commit/Skip/Cancel remain connected to their existing consumers.

As a macOS recovery adaptation, the inherited private/default preference domain stores one draft under the repository's canonical path. Its Codable identity includes original HEAD, branch, onto, stopped occurrence, step, applied HEAD and phase, comparing Git names by UTF-8 identity. Same-phase reopening restores even an empty draft. A changed HEAD or stopped occurrence rejects it; completing or aborting clears it. User text is never used as a Git argument. The draft is not an approval token: every continuation still validates actual replay state/HEAD.

The owned preparation has cancellation, access retention and preparation counters through the actual return. A cancelled write is recovered as a durable handoff, not reported as an applied commit. Commit sheets inherit the Rebase owner's alpha before presentation; the existing Commit owner manages its progress, message/author helpers and cleanup. Ordinary parent Close/Quit respects owned preparation and child windows; forced retirement cancels work and closes children.

Grouped validation

qa/rebase-message-edit-native-2026-10-18.swift exports RebaseMessageEditVerification.verify() for the grouped receiver. It uses private repository/preferences, hidden owned windows and the app's editor helper. It exercises advanced Cherry Pick with attribution, author/date context, draft refresh/reopen, actual checked Commit amend cancellation and acceptance, applied parent/author/date preservation, next-Edit message/undo/binding retirement, empty draft preservation and successful cleanup. Failure closes/drains owners and aborts only the test-owned replay.

RebaseMessageEditingTests adds three Core cases: clean/untracked/cancelled preparation; durable checked amendment with author/date options, excluded index preservation and reopening; and unstarted cancellation plus stale-HEAD draft identity. Existing snapshot, conflict-selection, Split and Squash coverage remains applicable. Results belong to the parent's grouped operation-workflow checkpoint; this implementation agent ran no builds or tests.

Remaining boundaries

This is not a visual audit of every Rebase control. The connected amend-failure recovery family covers the clean-worktree Retry/Ignore decision separately, including its own validation boundary. Windows-only taskbar and Scintilla implementation details use existing macOS progress/editor controls. Physical acceptance, signed deployment and complete hosted CI are not established by this focused family fixture.