gaps.md §4 carried two evidence paragraphs, an older one saying PRs #158
and #161 were open and a newer one saying all 2-D kinds survive XLSX round
trip, both repeating the resize, smooth-line, Switch Row/Column and
trendline statements. It is one paragraph with the current status again.
The Mainstream chart row in target-app-parity.md listed trendlines as
missing; they are read, written and drawn (`Series::trendlines`, the XLSX
chart reader and writer, `chart.addElement`), as chart-parity.md records.
The row now says so and keeps "no axis options". No score change.
gaps.md (§4), target-app-parity.md (the Essentials tier's work, the
Mainstream chart row, the interaction discount and the Essentials chart
task) and chart-parity.md (the element table and the work list) still
described charts as impossible to resize (#190). Charts move and resize
from eight handles like every floating object, so those statements now
say so; the 2026-10-10 revision rows and the 10-10 re-check stay as
history. Scores and the 40-60 h chart estimate are unchanged (resizing
was 1-2 h, within the rounding).
The sheet tracked the selected object as a bare id in `selected_chart`, so
only charts and text boxes drew a selection frame, only the bottom-right
corner resized, and the kind of the selected object had to be guessed from
the id. The selection is now `SheetApp::selected_object: Option<ObjRef>`,
with `selected_chart()` kept for the Chart Design tab and the Format Chart
pane.
- Model: `ObjKind` (chart, image, shape, slicer) and `ObjRef { kind, id }`;
`Sheet` helpers find, move and remove an object by `ObjRef` and walk every
object's anchor in a fixed order. `next_object_id` saturates instead of
overflowing on an id at `u32::MAX` read from a file.
- Commands: `object.delete`, `object.move` and `object.setAnchorMode` accept
the four kinds through one parameter check, refuse an unknown kind or id
instead of succeeding silently, and clamp hostile offsets. `object.delete`
replies with the deleted object. Arrange and the Selection Pane include
slicers, which stack above the other objects.
- Sheet: the selected object of any kind draws a frame with eight handles
over every object. Each handle resizes only its own edges, which never
cross; the body moves the object, and the first drag frame already applies
the pointer's movement. The pointer shows the handle's resize cursor or a
move cursor, with the diagonals swapped on a right-to-left sheet, where the
frame moves with its object.
- Keys: Escape drops the object selection; Delete and Backspace keep
deleting the selected object (#213). A selection whose object disappears
(undo, redo, delete, sheet switch) is cleared.
- Double-click: `open_object` routes by kind (a text box edits in place, a
chart opens Format Chart).
- Control protocol: `ui.inspect` reports `selectedObject {kind, id}` and
keeps `selectedChart`; `ui.object.select` selects any object and replies
with its rect. The snapshot example takes `--object <id>`.
Tests: engine tests for every kind by kind and id, the Selection Pane and
hostile parameters; UI tests for selecting each kind (a slicer over a chart
takes the click), all eight handles on four kinds, cursors, Delete,
Backspace and Escape, undo and redo, double-click routing, and resizing on a
right-to-left sheet. Existing tests use the new selection API.