A graph in a legacy .ai, or in a current file's editing data, is written
as `%_Gs`, its data and settings on `%_` lines, its drawn art in a group
with a `%_... Go` tag after each object, and `%_GS`. The reader stopped
on the graph operators as ones it doesn't know, so such a file did not
open through its layers.
The reader now leaves the graph's records out with their operands and
reads the drawn art as usual: the bars, lines and labels come in as the
groups, paths and type they are written as. Paint operators on `%_`
lines between `Gt` and `GT` set nothing. One note per file says the
graphs came in as plain art without their data or settings. A graph
that starts inside another, or doesn't end before its layer does, keeps
the art read so far with a second note. Graph operators outside a graph
stay unknown.
In editing data and legacy .ai files, a lower-case l, c, v or y makes the
anchor the segment ends on smooth and an upper-case L, C, V or Y makes it a
corner. The reader used to guess each anchor's kind from whether its
handles are in line, so a lower-case l always read as a corner and an
upper-case C with handles in line read as smooth. A closed path's first
anchor takes the case of the segment back to it. Points and handles do not
move. Paths, compound paths, clipping paths, guide paths, area type frames
and type-on-a-path paths all keep the kinds.
Add the progress line for the symbol editing follow-ups next to the Symbol
editing mode entry in docs/target-app-parity.md, with the tests that cover
them.
Symbol editing copies the editing layer's art into the symbol before Text Wrap, list numbering and threaded re-flow update that layer, so moving a wrap object in the edit left the symbol, its other instances and the saved file with the old wrap. The edit now syncs the symbol again after those passes, and when that changes the symbol, inline graphics of it are refreshed and the threads holding them re-flow.
The appearance changes of the instances on the layers now follow the edited objects through the same pass as the instances in other symbols, graph designs, pattern tiles and brushes. That pass also reaches instances used as opacity-mask art, which keep their changes on the same objects when an edit reorders them and drop the change to an object the edit deletes.
Entering symbol editing mode from an instance puts a copy of the symbol's art on the editing layer in the instance's place, and the instance stays in the document. The view drew the instance dimmed under the copy, so art with transparency showed darker, and its edges showed a dimmed fringe.
The renderer now leaves that instance out of the screen view while the editing layer is isolated, with its masks and effects, and in Outline view inside a clip group. Exports and thumbnails draw it as before.
Editing a dynamic symbol moved each placed instance's appearance changes with the objects they
name, but an instance stored in the art of another symbol kept its changes at the old paths, so
placing that symbol showed a change on the wrong object. Those instances, opacity masks included,
now follow the edit too and keep only the changes to objects the art still has.
BFlat