Compare and Merge pane-header workflows

Pinned TortoiseGit source: 7338078f8ddd924b8cddee35f512f2286072136d. This is a connected continuation of pane identity and status, not certification of the complete editor.

Source behavior

TortoiseMerge/BaseView.cpp::OnContextMenu (2398–2453) treats the filename header separately from the editor text. With the bottom/result view visible, the left and right headers offer Show diff separately (IDS_HEADER_DIFFLEFTTOBASE / IDS_HEADER_DIFFRIGHTTOBASE, Resources/TortoiseMergeENG.rc 1200–1201). The bottom header offers Explore To with IDI_EXPLORER.

MainFrm.cpp::DiffLeftToBase, DiffRightToBase and DiffTwo (1286–1315) launch a separate comparison of the original Base and Theirs/Mine files, in that order, preserving their descriptive window names. It is not a comparison of the edited result with the clicked source. The source Save As and input-rebinding semantics remain those described in source-pane tools and Save workflows.

Native implementation and adaptations

The classic native header now has a real AppKit context menu. Source headers expose Show diff separately through the existing independent comparison workflow. That workflow uses the accepted original Base and selected source bytes, including a source's accepted Save As target, not the mutable result or alignment display text. It carries descriptive pane titles independently from the private snapshot filenames. The independent child owns its read-only snapshots until the child closes and its reads drain; closing the parent does not silently invalidate an independent comparison.

The native snapshot adaptation deliberately compares the accepted document's source version. Upstream launches another process against live filenames. Keeping an externally changed input retains its older accepted version in the native editor until Reload or a separately accepted Save As; this command does not silently bypass that choice by rereading outside the document's existing grants.

Reveal in Finder is the macOS adaptation of Explore To. It uses a captured actual live input, rebound Save As target, or known existing merged output. Reflected/descriptive labels, historical object names and private immutable comparison snapshots are not filesystem destinations. An unnamed result has no Reveal command until an output has been accepted. A repository result-copy Save As retains its established copy-versus-normal-save semantics; it does not silently change the original result target just to reveal the copy.

The connected native header menus also reuse existing Save this pane as… / Save merged result as… actions. These additions are native conveniences, not claims that upstream exposes those commands in every header. Two-pane and combined Compare use the same existing saved-target writer. Optional Base preview exposes only a known live-file Reveal, without inventing Base editing or a Base-versus-result comparison. The compact P4-style headers reuse the same captured command availability and dispatch, without changing their filename, source-choice buttons or layout.

Classic headers retain left-click and accessibility-press pane focus. Their context menu is available by right-click, Shift-F10 while the header has keyboard focus, and the accessibility Show Menu action; individual custom accessibility actions use the same command receipts. Original Compare/Save As/Explorer artwork respects the owning context-menu icon preference. The P4-style filename field uses the same native header menu adapter in a compact presentation. Reopening it creates a fresh invocation even after Reveal, which does not publish a model change. Physical keyboard and VoiceOver acceptance still require separate review.

Each captured command binds its exact model, window, pane role, generation, source layout/result presentation, current attached native pane, preference epoch and raw target-path bytes. Busy work, sheets, an application-modal window, Quit, retirement, pane exchange, new output adoption and File/Open replacement refuse stale dispatch. Native menu and accessibility invocations are consumed once; fetching a fresh menu/action creates a fresh receipt. A nil-window interval invalidates old native header commands even when the same view later reattaches. A coalesced attached-pane identity notification refreshes header receipts after readonly source or optional Base mounting, even when focus, column and mark counts do not change; attaching or detaching a view schedules that update without reloading or changing selection. Save As retains the existing owned panel, cancellation, grant, guarded-write and late-answer fences. No new Git operation, repository adoption or permission bypass is introduced.

Implementation: MergePanePresentation.swift, FileComparisonWindow.swift, TextConflictWindow.swift and MergeSourceComparisonWindows.swift.

Verification and remaining scope

The new receiver qa/merge-pane-header-native-2026-10-25.swift and cached runner scripts/test-merge-pane-header.py author three grouped scenarios: Compare saved paths/Save As/combined replacement, source/result Merge comparison and exports, and menu/accessibility/detach/owner cancellation. They use private repositories, preferences and offscreen windows, and retain HEAD/index/input-byte witnesses. The affected Debug build and six cumulative native case/engine pairs pass; the dated record retains the initial failures, startup/mount repairs, fixture settlement fixes and exact validation scope. The initial system Compare pass was retained rather than repeated after Merge-only repairs. Two original two-pane Compare captures were reviewed in light and dark appearances; they do not establish three-pane Merge visual parity. No Core implementation changed in this family.

Physical context-menu/keyboard/VoiceOver use, every P4-style accessibility route, all file-provider/sandbox grants, minimum-version/Intel behavior, signed installed acceptance and full hosted CI remain separate acceptance work. Complete source menu/layout equivalence and all editor workflows are not established by this family.

Installed acceptance corrections

Actual build 7 three-pane acceptance found three connected presentation gaps: the Merge interface selector still occupied a large labelled left-side control; the separate source comparison's window title exposed its private snapshot path; and the accessible hierarchy exposed a static label without its owning header menu. These findings supersede any inference of installed three-pane or VoiceOver acceptance from the earlier offscreen case passes.

The authored correction gives both Classic and P4 three-pane layouts one compact, right-aligned menu selector using the same captured AppStorage setting and busy/Quit gates as Compare. Separate source frames now use the captured source descriptions in the title. MainFrm.cpp::SetWindowTitle (3117–3154) supplies the shortening/order policy: Mine first, Base as fallback, both only for distinct short names. Full descriptions remain pane labels; immutable physical paths remain locations/tooltips and identity, never replaced by descriptive metadata. The header explicitly participates as an accessible button; its visual label is ignored as a separate child. Show Menu, per-command custom actions and keyboard focus retain the existing one-shot/current-owner/modal/detachment fences.

The existing native receiver now also checks the public accessibility hierarchy contains the owning header button in Compare and P4, rather than relying solely on direct action methods, and checks the separate frame's captured descriptive title. The correction checkpoint and new installed/physical/VoiceOver acceptance are pending; the earlier six native pairs do not validate these subsequent edits.

The first correction checkpoint's Compare/system case failed the new in-process AX-tree oracle despite the header's direct native button properties; a containment retry failed the same oracle. Both attempts remain recorded. An isolated public AppKit/SwiftUI control showed that the in-process hosting-view children also omit a standard SwiftUI Button, while the actual system AX server exposes both that control and the explicitly accessible native header button and its named actions. finishLaunching is required for the receiver's system AX server; querying the in-process hosting-view tree is not equivalent.

The unnecessary containment change was removed. The fixture now queries only its own process through public AXUIElement APIs, without requesting permission, and requires an existing standard Save button as a control before asserting the header's exact description/help, button role, Show Menu and complete named action set. Existing direct retained-action dispatch still checks one-shot and owner/detachment fences; this does not claim a separate external assistive client dispatched those actions. The affected grouped checkpoint remains pending.

The first true-system-AX Compare/system case passed. The following Merge/system case found that accepted document loading still overwrote the previously configured source frame title with the private snapshot path. The repair now uses one computed title policy in initial controller creation, metadata setup and every accepted load, including reload and side swaps. Captured descriptions follow physical input identity when panes exchange; ordinary and image titles retain their previous path/IDiff policy. The existing source-child scenario now checks reload plus a round-trip side swap and original input bytes. This focused repair's checkpoint remains pending; earlier title assertions are not a pass.

Final local correction checkpoint

The correction receipt records the final grouped six scenario/engine pairs passing after the preserved AX-oracle and real load-title repairs. System and bundled Git pass Compare, Merge and ownership scenarios; all six receivers are independently absent. The actual self-process macOS AX tree exposes the button, Show Menu and named actions, with a standard Save button as a control. Direct guarded action dispatch remains separate from an external assistive-client interaction claim. Installed build 7 predates these source corrections; signed/physical VoiceOver and full-dialog acceptance remain open.